Principles MCQs

Question 1

On a blood test, an increase in what cell indicates acute infection?

A – Polymorph

B – Monocyte

C – Histiocyte

D – Monomorph

E – Lymphocyte

Answer 1

A - Polymorph

Polymorph is another name for neutrophil which relates to its polymorphous nucleus (typically 4 or 5 lobes). A monocyte is the name given to macrophages that are still in the blood stream. We call them macrophages when they reach the tissues. A histiocyte is an umbrella term for types of macrophages. A monocyte is therefore a kind of histiocyte. There is no such thing as a monomorph. Lymphocytes are a cell of chronic inflammation.

Question 2

Suppuration tends not to involve:

A – Necrosis

B – Phagocytosis

C – Abscess formation

D – Lymphocytes

E - Neutrophils

Answer 2

D - Lymphocytes

Suppuration is one of the outcomes of acute inflammation and broadly means the formation of pus. Necrotic debris is a main constituent of pus some of which will undergo phagocytosis by neutrophils. Lymphocytes are a cell of chronic inflammation. It should be noted that there is often some overlap between the outcomes of acute inflammation and that a degree of restitution, suppuration and chronic inflammation often coexist.

Question 3

Granulomas are not associated with:

A – Cancer

B – Lymphoma

C – Bacterial infection

D – Foreign material

E – Autoimmune disease

F – Viral infection

Answer 3

F - Viral infection

Granulomas are an aggregate of epithelioid histiocytes. Epithelioid is a term that means the macrophages look more like epithelial cells which in this context just means they are bigger and rounder. Granulomatous inflammation is relatively uncommon but is associated with several important disease processes many of which are rare but important not to miss.

Causes of granulomatous inflammation include

Tuberculosis and any other mycobacterial infection – this is one of the most important differential diagnoses and should always be kept at the back of your mind when someone mentions granuloma. Remember if it is a granuloma with caseating necrosis the diagnosis is TB until proven otherwise. Other infections frequently cause granulomatous responses but these are often fungal or parasitic. Viral infections do not typically cause granulomatous inflammation.

Foreign material is difficult to digest and phagocytose (like mycobacterium) and it often elicits a granulomatous response. Suture material after surgery is often associated with granulomas, as are inhaled agents and some illicit drugs.

Some autoimmune diseases show altered immune responses and result in granulomatous inflammation. Sarcoidosis is a multi-system disorder of unknown aetiology that is, however, likely to have an autoimmune basis. It is charactersied by the formation of well-formed granulomas. As it is a multi-system disorder it can result in granulomatous inflammation in any organ.

The final important point to remember is that some malignancies (lymphoma and carcinomas) can be associated with a granulomatous response.

Question 4

An autopsy on a 4 year old is performed. The father of the child claims that the boy fell off a climbing frame injuring his leg and then banging his head. He states that the injury occurred that morning. Which pathological feature in the bone would suggest that this is not true.

A – The presence of neutrophils

B – The presence of blood clot

C – The presence of fibroblasts

D – Vascular dilatation

E – High levels of complement at the injury site

Answer 4

C - The presence of fibroblasts

This is a slightly contrived question but does highlight to some extent why understanding the process of inflammation and healing is important. You should recall that one of the first changes in acute inflammation are the vascular changes. The vessels dilate and the rate of flow slows down allowing white cells to drift to the edges of the vessel. If there is significant vascular damage then a blood clot will form as a result of initiation of the coagulation cascade. Hopefully you now know that neutrophils are associated with acute inflammation and therefore the presence of neutrophils occurs early. Fibroblasts are a later feature at a point when the initial acute inflammation has died down. Immigration of fibroblasts into the damaged tissue is the first step towards forming granulation tissue and then either resolution or restitution of the site of injury.

Question 5

Resolution of injury and inflammation of the skin is more likely if there is:

A – Vascular disease

B – Persistence of the injury

C – Damage of the basement membrane

D – A poor nutritional state

E – Loss of the superficial layers of the epidermis

Answer 5

E - Loss of the superficial layers of the epidermis

We discussed the features of injury that are likely to favour complete healing or resolution.Healing tissue requires a supply of oxygen to produce ATP. ATP is the energy currency of all cells and cells in healing tissues will require lots of energy and therefore a good supply. Similarly, people in a poor nutritional state are less likely to be able to supply the correct building blocks in the form of protein, carbohydrate etc. that will be required for tissue to heal.

Persistence of the injury will continue to stimulate the same response that initiated the acute inflammation in the first place.

Epithelial tissues lie on a basement membrane. This provides them with a structure from which to grow. You may think of it as being analogous to having a scaffold in place to within which to build a house around. Without the scaffold in place it is difficult to completely build/repair the house. Therefore superficial injuries where the basement membrane remains intact heal well. This is relevant to traumatic injuries but is also important when we consider damage to the epidermis as a result of burns. 1^st degree burns are only superficial. 2nd degree burns involve the dermis and have therefore disrupted the basement membrane. 3^rd degree burns go even deeper and often into underlying connective tissue or fat.

Question 6

Located along the length of the testis at its posterioir aspect; its contents move in a superior to inferior direction.

A - Deep inguinal ring

B - Ejaculatory duct

C - Epididymis

D - Penile Urethra

E - Seminal vesicle

F - Seminiferous tubules

G - Spermatic cord

H - Tunica vaginalis

I - Ureter

J - Vas deferens

Answer 6

C - Epididymis

This structure is located at the posterior aspect of the testis. Sperm pass from the seminiferous tubules to the epididymis and then pass within the epididymis (in a superior to inferior direction) into the vas deferens which is the continuation of the epididymis at the inferior pole of the testis.

Question 7

Is sectioned (cut) and ligated (tied off) in a common male sterilisation procedure

A - Deep inguinal ring

B - Ejaculatory duct

C - Epididymis

D - Penile Urethra

E - Seminal vesicle

F - Seminiferous tubules

G - Spermatic cord

H - Tunica vaginalis

I - Ureter

J - Vas deferens

Answer 7

J - Vas deferens

The procedure is called a vasectomy, the derivation of this word: vas (vas deferens), ectomy (to cut out) (although note the vas deferens is not usually completely removed during this procedure). Although in theory, if any part of the route that sperm take from formation to ejaculation was completely interrupted (blocked or cut), it would render a male sterile, it is the vas deferens which is the easiest to access to achieve this. The vas is cut and ligated within the scrotum and a vasectomy can be carried out under local anaesthetic.

Question 8

Drains semen into prostatic urethra

A - Deep inguinal ring

B - Ejaculatory duct

C - Epididymis

D - Penile Urethra

E - Seminal vesicle

F - Seminiferous tubules

G - Spermatic cord

H - Tunica vaginalis

I - Ureter

J - Vas deferens

Answer 8

B - Ejaculatory duct

The Ejaculatory duct is formed from the vas deferens and the duct from the seminal vesicle joining together. The ejaculatory duct is located at the posteroinferior aspect of the bladder and it drains its contents (semen) into the prostatic urethra.

Question 9

Describe an encircling of skeletal muscle.

A - External anal sphincter

B - Filiform papillae

C - Kidney

D - Internal anal sphincter

E - Lacteal

F - Major duodenal papilla

G - Mesentery

H - Pyloric sphincter

I - Rugae

J - Splenic flexure

Answer 9

A - External anal sphincter

Question 10

Through this structure digestive enzymes enter the GI tract.

A - External anal sphincter

B - Filiform papillae

C - Kidney

D - Internal anal sphincter

E - Lacteal

F - Major duodenal papilla

G - Mesentery

H - Pyloric sphincter

I - Rugae

J - Splenic flexure

Answer 10

F - Major duodenal papilla

Question 11

Is usually located in the flank/lumbar region.

A - External anal sphincter

B - Filiform papillae

C - Kidney

D - Internal anal sphincter

E - Lacteal

F - Major duodenal papilla

G - Mesentery

H - Pyloric sphincter

I - Rugae

J - Splenic flexure

Answer 11

C - Kidney

Question 12

Is part of the axial skeleton and articulates with a cervical vertebra.

A - Acromial end of clavicle

B - Hyoid

C - Illium

D - Ischium

E - Mandible

F - Manubrium of sternum

G - Occipital bone

H - Rib 1

I - Rib 11

J - Sacrum

Answer 12

G - Occipital bone

It is located in the neurocranium and articulates with C1 (the atlas) at the atlanto­occipital joint.

Question 13

Does not articulate with any other bones

A - Acromial end of clavicle

B - Hyoid

C - Illium

D - Ischium

E - Mandible

F - Manubrium of sternum

G - Occipital bone

H - Rib 1

I - Rib 11

J - Sacrum

Answer 13

B - Hyoid

This bone is located in the anterior part of the neck, at the level of C3. This bone is described as “floating” as it is suspended by muscles that connect it to other bones and cartilage: the mandible, a part of the temporal bone (the styloid process), the thyroid cartilage (of the larynx), the manubrium of the sternum and the scapula.

Question 14

Forms a component of the pelvic outlet

A - Acromial end of clavicle

B - Hyoid

C - Illium

D - Ischium

E - Mandible

F - Manubrium of sternum

G - Occipital bone

H - Rib 1

I - Rib 11

J - Sacrum

Answer 14

D - Ischium

More specifically, it is the ischiopubic ramus (a specific part of the ischium) that forms the anterolateral aspect of the pelvic outlet, along with the coccyx posteriorly, the pubic symphysis anteriorly, the ischial tuberosities posterolaterally and the sacrotuberous ligament posterolaterally.

Question 15

Is part of a fibrous joint

A - Acromioclavicular joint

B - Atlanto-occipital joint

C - Distal radioulnar joint

D - Facet joint

E - Hip joint

F - Interosseus membrane

G -Knee joint

H - Shoulder joint

I - Temporomandibular joint

J - Wrist joint

Answer 15

F - Interosseus membrane

This is the fibrous sheet that connects 2 bones, e.g. the radius and ulna, or the tibia and fibula. The joint thus formed between the membrane and the bones is a type of fibrous joint known as a syndesmosis (fibrous sheet).

Question 16

A joint between C1 and a bone of the neurocranium

A - Acromioclavicular joint

B - Atlanto-occipital joint

C - Distal radioulnar joint

D - Facet joint

E - Hip joint

F - Interosseus membrane

G -Knee joint

H - Shoulder joint

I - Temporomandibular joint

J - Wrist joint

Answer 16

B - Atlanto-occipital joint

C1 is the 1 st cervical vertebrae, also known as the atlas, and the occipital bone is the bone that forms the posterior aspect of the neurocranium.

Question 17

A joint in which there is normally approximately 180° of flexion

A - Acromioclavicular joint

B - Atlanto-occipital joint

C - Distal radioulnar joint

D - Facet joint

E - Hip joint

F - Interosseus membrane

G -Knee joint

H - Shoulder joint

I - Temporomandibular joint

J - Wrist joint

Answer 17

H - Shoulder joint

180 degrees of flexion from the anatomical position is a large movement, so the answer is likely to be a joint that is highly mobile. That rules out A, D & F. Flexion does not occur at the distal radioulnar joint or the TMJ so that rules out C&I. At the remaining joints, flexion does occur however not 180 degrees (even though you have not been given values for the movements at the other joints, you can work this out just by undertaking the movements). The hip (as indicated in the lecture) has approx. 135 degrees of flexion. The knee joint approximately the same. The wrist joint will have a normal range of flexion less than that, approx. 90 degrees. You were asked in the learning objectives just to know the values for normal range of movements occurring at the shoulder, hip and knee joints.

Question 18

Site of production of ribosomes

A - Communicating junctions (gap junctions)

B - Desmosomes

C - Golgi apparatus

D - Microtubules

E - Mitochondria

F - Nucleolus

G - Occluding junctions (tight junctions)

H - Ribosomes

I - Rough endoplasmic reticulum

J - Smooth endoplasmic reticulum

Answer 18

F - Nucleolus

Ribosomes become associated to the rough endoplasmic reticulum in large numbers, indeed causing the ‘rough’ nature of the RER, however they are produced within the nucleus in the special region called the nucleolus, which typically appears as a dark ‘spot’ within the nucleus in both light micrographs and electron micrographs.

Question 19

Spread of electrical excitation directly from cell to cell

A - Communicating junctions (gap junctions)

B - Desmosomes

C - Golgi apparatus

D - Microtubules

E - Mitochondria

F - Nucleolus

G - Occluding junctions (tight junctions)

H - Ribosomes

I - Rough endoplasmic reticulum

J - Smooth endoplasmic reticulum

Answer 19

A - Communicating junctions (gap junctions)

Only one of these choices provides a direct cell­to­cell link between two cells which would allow direct spread of electrical excitation. That is the communicating, or gap, junctions, which consists of aligned pores in the adjacent membranes. Occluding junctions are sites of membrane contact, but do not provide direct communication, and although desmosomes involve contact between cells in the form of proteins inserted across the membrane, this interaction occurs in the extracellular space.

Question 20

Site where lipids are synthesised

A - Communicating junctions (gap junctions)

B - Desmosomes

C - Golgi apparatus

D - Microtubules

E - Mitochondria

F - Nucleolus

G - Occluding junctions (tight junctions)

H - Ribosomes

I - Rough endoplasmic reticulum

J - Smooth endoplasmic reticulum

Answer 20

J - Smooth endoplasmic reticulum

The principal site of lipid synthesis is the smooth endoplasmic reticulum. Most cells have relatively little of this, however in some cells, for example those producing steroid hormones, it is found in abundance. By contrast, the rough ER is the main site of synthesis for proteins destined for secretion, incorporation into the lumen of organelles, or incorporation into membranes.

Question 21

An avascular, typically polarised tissue that forms cohesive sheets, covering surfaces and lining cavities

A - Bone

B - Dense irregular connective tissue

C - Dense regular connective tissue

D - Epithelium

E - Glandular tissue

F - Loose connective tissue

G - Nervous tissue

H - Skeletal muscle

I - Smooth muscle

Answer 21

D - Epithelium

This is basically the definition of an epithelium. Most glandular tissue is epithelial in nature, however it would not fit the definition of ‘covering surfaces’ and ‘lining cavities’.

Question 22

Composed of very long elongated cells with each cell having multiple nuclei

A - Bone

B - Dense irregular connective tissue

C - Dense regular connective tissue

D - Epithelium

E - Glandular tissue

F - Loose connective tissue

G - Nervous tissue

H - Skeletal muscle

I - Smooth muscle

Answer 22

H - Skeletal muscle

Only skeletal muscle fulfils this. Certainly many neurons can be considered very elongated as they have long processes (typically axons), however neurons do not have multiple nuclei per cell.

Question 23

Composed mainly of packed, extracellular bundles of collagen fibres which are arranged in random directions

A - Bone

B - Dense irregular connective tissue

C - Dense regular connective tissue

D - Epithelium

E - Glandular tissue

F - Loose connective tissue

G - Nervous tissue

H - Skeletal muscle

I - Smooth muscle

Answer 23

B - Dense irregular connective tissue

Only connective tissue consists mainly of extracellular space and indeed fibres, thus we need to consider the different forms of connective tissue listed. The words that are key here are ‘packed’ which indicate a dense connective tissue, rather than a loose one, and ‘random directions’ which defines a dense irregular connective tissue.

Question 24

These cells appear striated, are branched and have a single nucleus that is located near their centre

A - Astrocytes

B - Cardiac muscle fibres

C - Chondrocytes

D - Mast cells

E - Microglial cells

F - Mucous cells

G - Oligodendrocytes

H - Osteocytes

I - Skeletal muscle fibres

Answer 24

B - Cardiac muscle fibres

If we just consider ‘striated’, there are only two cell types that we have discussed which are striated, skeletal muscle cells and cardiac muscle cells. However only cardiac muscle cells are branched (skeletal muscle cells are long ‘tube­like’ structures which do not branch) and have a single, central nucleus (skeletal muscle cells have many, many nuclei, which are located adjacent to the cell membrane).

Question 25

A form of glia responsible for producing myelin in the central nervous system

A - Astrocytes

B - Cardiac muscle fibres

C - Chondrocytes

D - Mast cells

E - Microglial cells

F - Mucous cells

G - Oligodendrocytes

H - Osteocytes

I - Skeletal muscle fibres

Answer 25

G - Oligodendrocytes

Three of the cell types listed are central nervous system glial cells: astrocytes, microglia and oligodendrocytes. Astrocytes have a number of functions including support and maintaining homeostasis in the extracellular environment, microglia are immune surveillance cells, but only oligodendrocytes produce myelin in the CNS (as opposed to Schwann cells, which produced myelin in the peripheral nervous system).

Question 26

The resident cells within cartilage

A - Astrocytes

B - Cardiac muscle fibres

C - Chondrocytes

D - Mast cells

E - Microglial cells

F - Mucous cells

G - Oligodendrocytes

H - Osteocytes

I - Skeletal muscle fibres

Answer 26

C - Chondrocytes

Chondrocytes are the resident cells of cartilage. Indeed the prefix ‘chondro’ means cartilage (comes from the Greek word for cartilage ‘chondros’).

Question 27

Enzymes are able to…

A - change the type of chemical reaction

B - increase the velocity of a reaction by raising the energy of activation

C - increase the velocity of a reaction by decreasing the energy of activation

D - increase the velocity of a reaction by reducing the change in free energy between substrates and products

E - work at any temperature

Answer 27

C - increase the velocity of a reaction by decreasing the energy of activation

Question 28

How many ADP molecules (per glucose) are phosphorylated to ATP via substrate phosphorylation reactions during glycolysis?​

A - 1

B - 2

C - 4

D - 6

E - 8

Answer 28

C - 4

For each glucose molecule that enters the glycolytic pathway, two ATP molecules are initially consumed to phosphorylate the glucose. Later, the phosphorylated hexose is split into two phosphorylated triose. Each triose­phosphate is converted into pyruvate, and in that process, two ATP molecules are formed per triosephosphate.

Question 29

Which of the following describes a transcription factor?​

A - It is a subunit of RNA polymerase II that does not have a prokaryotic analogue

B - It is a protein other than RNA polymerase that is involved in transcription

C - It is a sequence that determines whether an upstream element will be an enhancer or silencer

D - It is the part of the promoter sequence closest to the start of transcription

E - It is a complex of a protein and a nucleic acid

Answer 29

B - It is a protein other than RNA polymerase that is involved in transcription

Transcription factors are proteins, and are NOT subunits of RNA polymerase. Furthermore, they don’t contain nucleic acids. They also are NOT any sequences within the DNA of a cell, but most transcription factors can bind DNA in a sequence­specific manner, i.e. they will bind only to very specific DNA sequences.

Question 30

What kind of molecules do ribosomes consist of?​

A - RNA and proteins

B - DNA and proteins

C - Proteins and carbohydrates

D - RNA and DNA

E - RNA, proteins and carbohydrates

Answer 30

A - RNA and proteins

Ribosomes are nucleoprotein complexes and consist of rRNA molecules (four different ones in humans) and a large number of protein subunits, but no DNA or carbohydrates.

Question 31

Quaternary structure describes which of the following?

A - The relative orientation of one polypeptide to another polypeptide in a multisubunit protein

B - The overall shape of the polypeptide chain

C - Simple proteins with only one subunit

D - The sum of secondary and tertiary interactions

E - The path of the polypeptide backbone in three-dimensional space

Answer 31

A - The relative orientation of one polypeptide to another polypeptide in a multisubunit protein

Quaternary structure only refers to the relative orientation of different polypeptide subunits in a multisubunit complex. The overall shape of a polypeptide is termed its tertiary structure, and the path of the peptide backbone in three­dimensional space refers to secondary structure elements like helices and sheets.

Question 32

What is the direction of synthesis of DNA?

A - From the 5’end to the 3’end on both strands

B - From the 3’end to the 5’end on both strands

C - From the 5’end to the 3’ end on one strand and from the 3’ end to the 5’ end on the other strand

D - Only the template strand is copied in 3’ to 5’direction

E - Only the coding strand is copied in 5’ to 3’ direction

Answer 32

A - From the 5’end to the 3’end on both strands

During DNA synthesis both strands of a double helix are replicated. ALL nucleic acids are always polymerised from the 5’ end towards the 3’ end, because additional nucleotides can only be added to a free 3’ hydroxyl group.

Question 33

Which of the following statements best describes buffering capacity?

A - The extent to which a buffer solution can counteract the effect of added acid or base

B - The molecular weight of the substance used as a buffer

C - The pH of a buffer solution

D - The effectiveness of commercial antacids

E - The ratio between acid and conjugate base in solution

Answer 33

A - The extent to which a buffer solution can counteract the effect of added acid or base

The capacity of a buffer has nothing to do with the actual pH of the solution, nor the molecular weight of the buffering substance, nor with commercial antacids. The ratio between acid and conjugate base in solution determines the pH of this solution, but not how well a solution can buffer. The buffering capacity simply refers to how well a buffer can resist changes in pH when acid or base is added.

Question 34

Which ONE of the following is TRUE for the reduction of pyruvate to lactate?

A - It allows for the regeneration of NAD+

B - It is the process that aids in the recovery of sore muscles after exercise

C - It is accompanied by the phosphorylation of ADP

D - It does not occur in aerobic organisms

E - It only occurs in certain microorganisms

Answer 34

A - It allows for the regeneration of NAD+

This is a reaction that occurs in many microorganisms, but also in eukaryotic cells. It also occurs in highly active human muscle cells when not enough oxygen can be delivered to the cell for its requirements. As a consequence, the cell can not generate enough ATP by oxidative phosphorylation, but has to resort to substrate level phosphorylation using increased glycolysis. This generates more NADH than can be re­oxidised by the electron transport chain. To allow glycolysis to continue, NAD + has to be regenerated, that occurs by the reduction of pyruvate (the product of glycolysis) to lactate. This reaction is not linked to the phosphorylation of ADP. Lactate is actually involved in generating the muscle pain after strong exercise.

Question 35

With regard to signalling via G-proteins, which ONE of the following statements is CORRECT?

A - The process of guanine nucleotide exchange (i.e.GTP replacing GDP) occurs at the βγ subunit of the G-protein

B - β1 and β2 adrenoceptors signal through the Gi subtype of G-protein

C - Signalling is immediately terminated by agonist dissociating from the G-proteincoupled receptor

D - G-protein coupled receptors are a complex of five separate protein subunits

E - Signalling is terminated by hydrolysis of GTP to GDP by the GTPase activity of the G-protein α subunit

Answer 35

E - Signalling is terminated by hydrolysis of GTP to GDP by the BTPase activity of the G-protein a subunit

A) is incorrect as guanine nucleotide exchange occurs at the a subunit of the G­protein

B) is incorrect as all beta­adrenoceptors signal primarily through the Gs G­protein

C) is incorrect as dissociation of the agonist from the receptor has no effect on the activated G­protein

D) is incorrect as G­protein coupled receptors are a single protein

Question 36

Identify the statement that best describes the action of a competitive antagonist on the concentration response curve for an agonist acting on the same receptor when displayed on a plot of biological response (linear scale) versus agonist concentration (log scale).

A - The position of the agonist concentration response curve is shifted to the left in a parallel manner

B - The position of the agonist concentration response curve is unchanged, but the maximum response is depressed

C - The position of the agonist concentration response curve is shifted to the right in a parallel manner with no change in the maximum response

D - The position of the agonist concentration response curve is shifted to the right in a non parallel manner and a depression of the maximum response

E - The position of the agonist concentration response curve is shifted to the left in a non-parallel manner with no change in the maximum response

Answer 36

C - The position of the agonist concentration response curve is shifted to the right in a parallel manner with no change in the maximum response

A) is incorrect because a rightward parallel shift occurs

B) is incorrect because the maximal response is not depressed (this statement describes the action of a non­competitive antagonist)

D) is incorrect because the shift is parallel with no depression of the maximum response

E) is incorrect because the shift is parallel

Question 37

With respect to the autonomic nervous system, which ONE of the following statements is CORRECT?

A - Stimulation of the parasympathetic division causes ejaculation

B - Stimulation of the sympathetic division increases gastrointestinal motility

C - Stimulation of the sympathetic division decreases heart rate and force

D - Stimulation of the parasympathetic division increases the secretion of watery saliva

E - Stimulation of the sympathetic division causes bronchoconstriction

Answer 37

D - Stimulation of the sympathetic division decreases heart rate and force

A) incorrect – parasympathetic stimulation causes erection, sympathetic stimulation cause ejaculation

B) incorrect ­ sympathetic stimulation decreases motility of the G.I. tract

C) incorrect ­ sympathetic stimulation increases heart rate

E) incorrect – sympathetic stimulation causes bronchodilatation (via the release of adrenaline from the adrenal medulla)

Question 38

Which ONE of the following statements relating to ganglionic transmission is CORRECT?​

A - The excitatory postsynaptic potential (epsp) is caused by the activation of the nicotinic acetylcholine receptors composed of α3 and β4 subunits

B - Transmission is terminated by the reuptake of acetylcholine

C - Amphetamine causes the release of acetylcholine from pre-ganglionic nerve terminals by displacing acetylcholine from storage vesicles

D - The excitatory postsynaptic potential (epsp) is caused by the activation of nicotinic acetylcholine receptors composed of α4 and β2 subunits

E - Atropine selectively blocks transmission at this site

Answer 38

A - The excitatory postsynaptic potential (epsp) is caused by the activation of the nicotinic acetylcholine receptors composed of α3 and β4 subunits​

B) incorrect ­ transmission is terminated by hydrolysis of ACh by extracellular acetylcholinesterase

C) incorrect ­ amphetamine displaces noradrenaline for storage vesicles at noradrenergic synapses

D) incorrect ­ the a4b2 receptor is found in the CNS, not the autonomic ganglia

E) incorrect ­ atropine locks muscarinic, not nicotinic, ACh receptors

Question 39

Which ONE of the following acts as a presynaptic AUTORECEPTOR that inhibits the release of transmitter at sympathetic neuroeffector junctions?

A - β1-adrenoceptor

B - Muscarinic acetylcholine receptor

C - α1-adrenoceptor

D - α2-adrenoceptor

E - β2-adrenoceptor

Answer 39

D - α2-adrenoceptor

A) incorrect ­ b1 receptors are located, for example, in the heart

B) incorrect ­ muscarinic receptor can act as autoreceptors at parasympathetic neuroeffector junctions

C) incorrect ­ a1 receptors are located, for example, on vascular smooth muscle

D) correct

E) incorrect ­ b2 receptors are located, for example, in airway smooth muscle

Question 40

In relation to drug disposition, which one of the following statements is TRUE

A - The stomach is the major site of absorption of orally administered drugs

B - Ionised drugs of low molecular weight that are not protein bound move freely between most capillary circulations and the interstitial space

C - The absorption of orally administered drugs always occurs by passive diffusion

D - Polar drugs readily distribute by diffusion from the interstitial to intracellular spaces and vice versa

E - Drugs delivered by the enteral route always reach the systemic circulation via the portal circulation and the liver

Answer 40

B - Ionised drugs of low molecular weight that are not protein bound move freely between most capillaru circulations and the interstitial space

A) incorrect – the surface area of the stomach is much less than that of the small intestine. The latter is largely responsible for the absorption of orally administered drugs

B) correct

C) incorrect – some drugs (e.g. L­dopa), are absorbed via transport systems

D) incorrect – being polar such drugs cannot readily cross phospholipid bilayers unless assisted by transport systems

E) incorrect – the enteral route includes buccal, sublingual and rectal routes that either completely, or partially, avoid a ‘first pass’ through the liver

Question 41

With regard to the autonomic nervous system, which ONE of the following statements is CORRECT?

A - Fast chemical transmission through the sympathetic ganglia is mediated by noradrenaline (norepinephrine) released from pre-ganglionic nerve fibres

B - Parasympathetic pre-ganglionic nerve fibres originate from the thoracolumbar region of the spinal cord

C - Parasympathetic ganglia are usually distant to the organs that they innervate

D - The sympathetic nerve fibres innervating the adrenal medulla utilize acetylcholine as their neurotransmitter

E - Post-ganglionic sympathetic fibres utilize adrenaline (epinephrine) as their neurotransmitter

Answer 41

D - The sympathetic nerve fibres innervating the adrenal medulla utilize acetylcholine as their neurotransmitter

A) incorrect – the transmitter is always ACh

B) incorrect – the preganglionic fibres have a cranial, or sacral, outflow

C) incorrect – they are usually embedded in the target organ (with the exception of some ganglia in the head)

D) correct

E) incorrect – the transmitter is noradrenaline (with the exception of the innervation to the sweat glands where the transmitter is unusually ACh)

Question 42

A substrate for uptake 1 (U1) that causes the release of transmitter from sympathetic post-ganglionic neurons in a manner that does not require the opening of presynaptically-located voltage-activated Ca2+ channels.

A - Acetylcholine

B - Adrenaline (epinephrine)

C - Amphetamine

D - Atenolol

E - Atropine

F - Cocaine

G - Muscarine

H - Noradrenaline (norepinephrine)

I - Prazosin

J -Salbutamol

Answer 42

C - Amphetamine

The only other plausible alternative would be cocaine (F) which is ruled out because although it binds to U1 it is not transported as a substrate and does not cause Ca 2+ ­independent release of noradrenaline.

Question 43

Causes multiple organ effects by blocking neuroeffector transmission in the parasympathetic division of the autonomic nervous system by competitive antagonism of muscarinic acetylocholine receptors.

A - Acetylcholine

B - Adrenaline (epinephrine)

C - Amphetamine

D - Atenolol

E - Atropine

F - Cocaine

G - Muscarine

H - Noradrenaline (norepinephrine)

I - Prazosin

J -Salbutamol

Answer 43

E - Atropine

The only other drug that binds to muscarinic receptors is muscarine which is excluded because it is an agonist, rather than an antagonist

Question 44

A selective agonist of β2-adrenoceptors that mimics the relaxant effect of a circulating adrenal hormone upon airway smooth muscle

A - Acetylcholine

B - Adrenaline (epinephrine)

C - Amphetamine

D - Atenolol

E - Atropine

F - Cocaine

G - Muscarine

H - Noradrenaline (norepinephrine)

I - Prazosin

J -Salbutamol

Answer 44

J - Salbutamol

Atenolol (D) which also binds to b­adrenoceptors is excluded because it is an antagonist and b1 selective. Noradrenaline (B) is excluded as it is not b2 selective. Prazosin (I) is incorrect because it is an a1­blocker.

Question 45

Totally avoids first pass metabolism (presystemic elimination) yielding 100% systemic availability. Ideal for very rapid onset of action. Can result in high drug levels at the heart.

A - Buccal

B - Inhalational

C - Intramuscular

D - Intrathecal

E - Intravenous

F - Oral

G - Rectal

H - Subcutaneous

I - Sublingual

J - Topical

Answer 45

E - Intravenous

Clues are (i) 100% availability (ii) rapid onset of action and (iii) total avoidance of first pass. Collectively, these rule out any other option

Question 46

Infrequently (in UK) employed enteral route that partially avoids first pass metabolism (presystemic) elimination. Can be used for nocturnal administration.

A - Buccal

B - Inhalational

C - Intramuscular

D - Intrathecal

E - Intravenous

F - Oral

G - Rectal

H - Subcutaneous

I - Sublingual

J - Topical

Answer 46

G - Rectal

Buccal and sublingual are ruled out because those routes totally, rather than partially, avoid fist pass and they are hardly suited to nocturnal dosing.

Question 47

Parenteral route favoured for local effect of charged/polar compounds but also allowing rapid absorption of volatile agents.

A - Buccal

B - Inhalational

C - Intramuscular

D - Intrathecal

E - Intravenous

F - Oral

G - Rectal

H - Subcutaneous

I - Sublingual

J - Topical

Answer 47

B - Inhalational

None of the other routes match the description well

Question 48

The baroreceptor response to decreased mean arterial blood pressure includes all of the following except one.

A - Increased sympathetic activity to the heart

B - Increased total peripheral resistance

C - Decreased vagal activity

D - Arteriolar vasodilatation

E - Increased stroke volume

Answer 48

D - Arteriolar vasodilatation

The baroreceptor response to decreased mean arterial blood pressure includes arteriolar vasoconstriction and not arteriolar vasodilatation. Arteriolar vasodilation would decrease the total peripheral vascular resistance and hence further decreases (rather than increase) the mean arterial blood pressure. All the other options are part the baroreceptor response to decreased mean arterial blood pressure.

Question 49

The normal range of mean arterial blood pressure is about…

A - 80-120 mmHg

B - 70-105 mmHg

C - 60-130 mmHg

D - 90-140 mmH

E - 50-90 mmHg

Answer 49

B - 70-105 mmHg

A mean arterial blood pressure of at least 60 mmHg is needed to adequately perfuse the vital organs including e.g. the heart, brain and kidneys. The mean arterial blood pressure should be high enough to perfuse the body organs, but not too high to damage them, damage the blood vessels or place an extra strain on the heart.

Question 50

The resting membrane potential of a typical nerve cell is…

A - +50mV

B - +70mV

C - 0

D - -50mV

E - -70mV

Answer 50

E - - 70mV

Question 51

Select the ONE correct statement from the list below.

A - Feed forward occurs after the change has been detected

B - Positive feedback systems are the main type of control mechanisms in the human body

C - Negative feedback opposes the initial change in a controlled variable

D - Control of blood pressure is an example of a positive feedback system

E - Negative feedback opposes stability of the internal environment

Answer 51

C - Negative feedback opposes the initial change in a controlled variable

All the other statements are incorrect:

Feed forward occurs in anticipation of a change.

Negative feedback (and not positive feedback) systems are the main type of control mechanisms in the body.

Control of blood pressure is an example of a negative (and not positive feedback) system.

Negative feedback helps with (rather than opposes) stability of the internal environment.

Question 52

Select the ONE correct statement from the list below.​

A - Body temperatures of about 40-42 degrees Celsius indicates fever

B - Hypothermia is indicated by body temperature between 36.5 and 35.5 degrees Celsius

C - The anterior hypothalamic centre is stimulated by the cold

D - Vasoconstriction of the skin arterioles is caused by stimulation of parasympathetic nerves

E - Heat exposure decreases muscle tone

Answer 52

E - Heat exposure decreases muscle tone

All the other options are incorrect:

Body temperatures of 40­42 degree Celsius indicate hyperthermia.

Hypothermia is indicated by body temperature at or below 35 degree Celsius.

The anterior hypothalamic centre is stimulated by warmth not cold. The posterior hypothalamic centre is stimulated by cold.

Vasoconstriction of skin arterioles is caused by sympathetic and not parasympathetic nerves.

Question 53

Select the ONE correct statement from the list below.

A - Vasoconstriction decreases the total peripheral resistance and mean arterial blood pressure

B - Vascular smooth muscles are predominantly supplied by parasympathetic nerves

C - Stimulation of the vagus nerve slows down the heart rate

D - In the heart, the sympathetic tone dominates under resting conditions

E - The vasomotor tone is caused by tonic discharge of the parasympathetic nerves

Answer 53

C - Stimulation of the vagus nerve slows down the heart rate

The vagus nerve provides the parasympathetic supply to the heart.

All the other answers are incorrect: Vasoconstriction increases (rather than decreases) the total peripheral vascular resistance and mean arterial blood pressure.

Vascular smooth muscles are predominantly supplied by sympathetic rather than parasympathetic nerves.

Under resting conditions, the vgal tone and not the sympathetic tone dominate on the heart.

The vasomotor tone is caused by tonic discharge of sympathetic and not parasympathetic nerves.

Question 54

Which is a feature of Mitochondrial inheritance?

A - Where an individual is affected, 50% of their children will be affected

B - There is no male to male transmission of the condition

C - Where one child is affected in the family, the risk of the next child, to the same parents being affected is 1 in 8

D - Where one child is affected in the family, the risk of the next child, to the same parents, being affected is 1 in 4

E - The condition can only be transmitted from an affected father to his children

F - The condition can only be transmitted from an affected mother to her children

G - A female gene carrier will not show any evidence of disease

H - A male who carries the disease-causing mutation will not show any signs of the condition

Answer 54

F - The condition can only be transmitted from an affected mother to her children

Mitochondrial DNA is inherited from the mother.

Question 55

Which is a feature of Autosomal recessive inheritance?

A - Where an individual is affected, 50% of their children will be affected

B - There is no male to male transmission of the condition

C - Where one child is affected in the family, the risk of the next child, to the same parents being affected is 1 in 8

D - Where one child is affected in the family, the risk of the next child, to the same parents, being affected is 1 in 4

E - The condition can only be transmitted from an affected father to his children

F - The condition can only be transmitted from an affected mother to her children

G - A female gene carrier will not show any evidence of disease

H - A male who carries the disease-causing mutation will not show any signs of the condition

Answer 55

D - Where one child is affected in the family, the risk of the next child, to the same parents, being affected is 1 in 4.

Only one child affected so the parents must be carriers (heterozygous).

Question 56

Which is a feature of X-linked recessive inheritance?

A - Where an individual is affected, 50% of their children will be affected

B - There is no male to male transmission of the condition

C - Where one child is affected in the family, the risk of the next child, to the same parents being affected is 1 in 8

D - Where one child is affected in the family, the risk of the next child, to the same parents, being affected is 1 in 4

E - The condition can only be transmitted from an affected father to his children

F - The condition can only be transmitted from an affected mother to her children

G - A female gene carrier will not show any evidence of disease

H - A male who carries the disease-causing mutation will not show any signs of the condition

Answer 56

B - There is no male to male transmission of the condition

Since males only have one X chromosome and male progeny receive their X-chromosome from the mother, any defect on the paternal X-chromosome will not be passed on to male progeny.

Question 57

Select the phenotype most likely for an individual with the normal number of autosomes, but only one X chromosome

A - A child with multiple malformations and severe learning difficulties

B - A child with Down syndrome

C - A male with normal intelligence and infertility

D - A normal female

E - A female with normal intelligence and infertility

F - A normal male

G - A child with achondroplasia

Answer 57

E - A female with normal intellegence and infertility

Turner’s syndrome.

Question 58

Select a phenotype for An individual with a balanced translocation between chromosomes 2 and 7, and two X chromosomes

A - A child with multiple malformations and severe learning difficulties

B - A child with Down syndrome

C - A male with normal intelligence and infertility

D - A normal female

E - A female with normal intelligence and infertility

F - A normal male

G - A child with achondroplasia

Answer 58

D - A normal female

In constitutional balanced translocations there is commonly no abnormal phenotype since there is no loss or gain of DNA.

Question 59

Select a phenotype for a baby born with 3 copies of chromosome 21 and two X chromosomes

A - A child with multiple malformations and severe learning difficulties

B - A child with Down syndrome

C - A male with normal intelligence and infertility

D - A normal female

E - A female with normal intelligence and infertility

F - A normal male

G - A child with achondroplasia

Answer 59

B - A child with Down synrome

Trisomy 21 - constitutional

Question 60

Scientists in the department of Genetics at Ninewells Hospital are analysing transcripts within bone marrow cells from patients attending the Haematology department. Which of the following best describes the material the analysis is being performed on?​

A - Genomic DNA

B - Histones

C - RNA

D - Chromosomes

E - Amino Acids

F - Protein

G - Mitochondrial DNA

Answer 60

C - RNA

Question 61

A malignant tumour derived from a glandular epithelial surface is known as:

A - An adenoma

B - An adenosarcoma

C - A squamous carcinoma

D - An adenocarcinoma

E - A malignant teratoma

Answer 61

D - An adenocarcinoma

Adeno’ pertaining to a gland, ‘carcinoma’ meaning cancer (malignant).

Question 62

Which ONE of the following statements is FALSE?

A - Hypertrophy causes tissue enlargement as a result of increased cell size

B - Atrophy may be reversible

C - Hypoplasia is a developmental disorder

D - Hyperplasia is reversible

E - Apoptosis is always indicative of a pathological disorder

Answer 62

C - Hypoplasia is a developmental disorder

Apoptosis can also be a physiological response e.g. during embryonic development or T cell development.

Question 63

Which ONE of the following statements is TRUE?

A - “Differentiation” is a term that describes the stage of cancer

B - The prognosis for all types of cancer is poor

C - The prognosis declines with increasing stage of disease

D - Staging of cancer is based only on histological examination of the resected tumour

E - Co-existent diseases will not affect the clinical management decisions or the prognosis

Answer 63

C - The prognosis declined with increasing stage of disease

As the cancer starts to involve additional anatomical areas (stage) the prognosis worsens

Question 64

Which of the following terms describes enlargement of an organ as a result of increased size of cells within it?

A - Hypertrophy

B - Atrophy

C - Hyperplasia

D - Hypoplasia

E - Metaplasia

Answer 64

A - Hypertrophy

Fact - increase in cells would be hyperplasia.

Question 65

Which of the following viruses is commonly associated with malignant epithelial tumours in humans?

A - Rous sarcoma virus

B - Cytomegalovirus

C - Human Papilloma Virus

D - Measles

E - Hepatitis A Virus

Answer 65

C - Human papilloma Virus

The intended answer is Human Papilloma Virus. The others do not cause cancer in man.

Question 66

A specific protein that is commonly inactivated in cancer​

A - Bcl-2

B - Caspase

C - Cathepsin

D - Classical oncogenes

E - c-myc

F - Oestrogen receptor

G - p53

H - Platelet derived growth factor

I - ras

J - Tumour suppressor proteins

Answer 66

G - p53

The gene TP53 is often mutated in cancer and results in a non-functional protein.

Question 67

A family of proteins activated in cascade like fashion that are responsible for the common end stages of inducing apoptosis

A - Bcl-2

B - Caspase

C - Cathepsin

D - Classical oncogenes

E - c-myc

F - Oestrogen receptor

G - p53

H - Platelet derived growth factor

I - ras

J - Tumour suppressor proteins

Answer 67

B - Caspase

Fact - hence the ion of these proteins result in uncontrolled proliferation and survival of cells.

Question 68

A protein activated in Burkitt’s lymphoma

A - Bcl-2

B - Caspase

C - Cathepsin

D - Classical oncogenes

E - c-myc

F - Oestrogen receptor

G - p53

H - Platelet derived growth factor

I - ras

J - Tumour suppressor proteins

Answer 68

E - c-myc

Fact - due to chromosomal translocations that juxtapose c-myc with immunoglobulin gene promotes (usually heavy chain e.g. t(8 ;14))

Question 69

The initiating event in atheroma is…

A - Endothelial injury

B - Hypertension F

C - Intimal accumulation of macrophages

D - Leukocyte chemotaxis

E - Needle shaped cholesterol crystals

F - Plaque rupture

G - Platelet production of PDGF

H - Proliferation of medial smooth muscle

Answer 69

A - Endothelial injury

Question 70

Fatty streak formation is a result of…

A - Endothelial injury

B - Hypertension F

C - Intimal accumulation of macrophages

D - Leukocyte chemotaxis

E - Needle shaped cholesterol crystals

F - Plaque rupture

G - Platelet production of PDGF

H - Proliferation of medial smooth muscle

Answer 70

C - Intimal accumulation of macrophages

Question 71

Coronary artery thrombosis is often triggered by…

A - Endothelial injury

B - Hypertension F

C - Intimal accumulation of macrophages

D - Leukocyte chemotaxis

E - Needle shaped cholesterol crystals

F - Plaque rupture

G - Platelet production of PDGF

H - Proliferation of medial smooth muscle

Answer 71

F - Plaque rupture

Question 72

Which of the following is a virus which can reactivate from a latent state to cause disease? Select the ONE CORRECT answer from the following list of options.

A - Rabies virus

B - Human papilloma virus

C - Herpes simplex virus

D - Adenovirus

E - Influenza A virus

Answer 72

C - Herpes simplex virus

The correct answer is Herpes Simplex Virus, latency is characteristic of the herpes viruses. None of the other options are herpes viruses.

Question 73

Choose the MOST LIKELY route of infection for a 19 year old male student that develops a yellow urethral discharge 2 weeks after a holiday in Ibiza.

A - Blood-blood spread

B - Direct contact

C - Endogenous infection

D - Faecal-oral route

E - Insect vector spread

F - Overgrowth of normal flora

G - Respiratory route

H - Sexual intercourse

I - Vertical transmission

J - Zoonosis

Answer 73

H - Sexual intercourse

Unprotected sexual intercourse is the most likely explanation as the symptoms suggest a sexually transmitted infection.

Question 74

Choose the most likely route of infection for a 30 year old male who develops vomiting, diarrhoea and abdominal pain lasting for 5 days following a holiday in Bulgaria

A - Blood-blood spread

B - Direct contact

C - Endogenous infection

D - Faecal-oral route

E - Insect vector spread

F - Overgrowth of normal flora

G - Respiratory route

H - Sexual intercourse

I - Vertical transmission

J - Zoonosis

Answer 74

D - Faecal-oral route

The symptoms of gastroenteritis are most likely due to food poisoning (acquired via the faecal oral route).

Question 75

Choose the most likelu route of infection for a 30 year old male who has jaundice and deranged liver function tests 3 months after a holiday in Turkey. He admits to getting a new tattoo in a tattoo parlour for a dare whilst on holiday

A - Blood-blood spread

B - Direct contact

C - Endogenous infection

D - Faecal-oral route

E - Insect vector spread

F - Overgrowth of normal flora

G - Respiratory route

H - Sexual intercourse

I - Vertical transmission

J - Zoonosis

Answer 75

A - Blood-blood spread

Hepatitis A is unlikely as the incubation period is less than 6 weeks (and is mainly spread via the faecal oral route): hepatitis C unlikely, though it can be spread via tattooing practices the incubation is usually less than 12 weeks and 90% don’t have jaundice. This is most likely to be hepatitis B, spread by blood to blood contact on improperly sterilised equipment, the incubation period is 6 weeks to 6 months and about half of infected adults have jaundice.

Question 76

Expressed on the surface of macrophages and mediates recognition of bacteria

A - B cell receptor

B - C-reactive protein

C - CD8

D - Immunoglobulin IgD

E - Immunoglobulin IgE

F - Leucocyte adhesion molecule

G - Membrane attack complex

H - Pattern recognition receptor

I - Tumour necrosis factor

Answer 76

H - Pattern recognition receptor

Innate immune cells such as macrophages recognise pathogens using PRRs (Pattern Recognition Receptors).

Question 77

Binds directly to encapsulated bacteria to cause cell death by osmotic lysis

A - B cell receptor

B - C-reactive protein

C - CD8

D - Immunoglobulin IgD

E - Immunoglobulin IgE

F - Leucocyte adhesion molecule

G - Membrane attack complex

H - Pattern recognition receptor

I - Tumour necrosis factor

Answer 77

G - Membrane attack complex

The Membrane Attack Complex (MAC) of the complement system can directly lyse pathogens via membrane insertion and osmotic lysis.

Question 78

An important mediator of opsonisation of bacteria by phagocytes

A - B cell receptor

B - C-reactive protein

C - CD8

D - Immunoglobulin IgD

E - Immunoglobulin IgE

F - Leucocyte adhesion molecule

G - Membrane attack complex

H - Pattern recognition receptor

I - Tumour necrosis factor

Answer 78

B - C-reactive protein

Proteins of the immune system that can promote pathogen phagocytosis are known as Opsonins (the process is known as Opsonisation). Opsonins include the acute phase protein C reactive protein, the complement protein C3b and antibodies of the IgG class.

Question 79

A key complement system protein

A - CD4

B - Factor I

C - C3

D - Membrane attack complex

E - C-reactive protein

F - TNF alpha

G - IgM

H - Lipopolysaccharide

Answer 79

C - C3

C3 is the key mediator of the complement system - it is activated by all three activation pathways.

Question 80

A cytokine that is produced during the acute inflammation

A - CD4

B - Factor I

C - C3

D - Membrane attack complex

E - C-reactive protein

F - TNF alpha

G - IgM

H - Lipopolysaccharide

Answer 80

F - TNF alpha

Only cytokine in possible answers (TNF)

Question 81

Cell type of fundamental importance for the initial innate immune response

A - Neutrophil

B - CD4 T Lymphocyte

C - Natural Killer Cell

D - Mast cell

E - Liver cell

F - B Lymphocyte

G - Plasma cell

H - Antigen Presenting Cell

Answer 81

A - Neutrophil

Neutrophils play a critical role in the early innate immune response. This is therefore the best answer. Mast cells are also involved in some responses e.g. allergy, but overall, neutrophils are much more important.

Question 82

Cell type that produces C-reactive Protein (CRP)

A - Neutrophil

B - CD4 T Lymphocyte

C - Natural Killer Cell

D - Mast cell

E - Liver cell

F - B Lymphocyte

G - Plasma cell

H - Antigen Presenting Cell

Answer 82

E - Liver cell

Question 83

Which is likely to influence the health of a 40 year old business man who is unable to exercise due to time pressures?

A - Cultural

B - Economic

C - Employment

D - Environment

E - Genetic

F - Geographical

G - Lifestyle

H - Medical services

I - Personality

J - Social support

Answer 83

G - Lifestyle

His job is so busy that his perception is that he has no time to exercise. In fact, this may not be the case, and if he were your patient, you would be trying to find ways of incorporating exercise into his daily routine, rather than suggesting he alters that routine dramatically. Other possible answers might have been C or I, but the best place to start is to try to alter his lifestyle.

Question 84

Which is likely to influence the health of a 78 year old man in the UK who is recently widowed and whose family live in Australia?

A - Cultural

B - Economic

C - Employment

D - Environment

E - Genetic

F - Geographical

G - Lifestyle

H - Medical services

I - Personality

J - Social support

Answer 84

J - Social support

The man has just lost his wife (you can assume they were married for along time) and will be going through the grieving process, trying to find a new routine for life, and handling all of the administrative and financial issues associated with a death. He is having to do this without the immediate, physical and practical support of his family, as they are on the other side of the world. Whilst they may be very supportive in principle, there’s a limit to what can be done on the phone or email.

Question 85

Which is likely to influence the health of a 24 year old aid worker in a refugee camp during an outbreak of a diarrhoeal illness?

A - Cultural

B - Economic

C - Employment

D - Environment

E - Genetic

F - Geographical

G - Lifestyle

H - Medical services

I - Personality

J - Social support

Answer 85

D - Environment

The biggest immediate threat to the health of this worker is from infection. That risk will be moderated by other environmental factors, such as access to clean water and sanitation. Possible other factors might be G, as individual behaviour can alter risk (handwashing for example); or H, as if they do get infected, the medical support may be rudimentary at best.

Question 86

Which is the most appropriate use for alcohol gel?

A - For routine hand washing in clinical areas (wards)

B - Is the preferred cleansing agent for all interactions

C - Only to be used if no other cleansing agents are available

D - In between patients when hands are socially clean

E - To be used following exposure to MRSA

Answer 86

D - In between patients when hands are socially clean

A, B, C, E are incorrect as if hands soiled exposure to MRSA, C. difficle due to perform aseptic procedure or used gel several times need to wash hands.

Question 87

Which is the most appropriate bag to dispose of confidential waste?

A - Black bag

B - Blue bag

C - Orange bag

D - Red bag

E - Yellow bag

Answer 87

B - Blue bag

B: Correct - confidential.

A: Household waste.

C: Clinical waste.

D: Semi-clear red for soiled laundry.

E: Theatre / anatomy clinical waste e.g. amputated digits.

Question 88

The abbreviation PPE stands for:

A - Patient’s Personal Expectations

B - Patient’s Protective Equipment

C - Personal Protective Equipment

D - Professional’s Personal Expectations

E - Philosophy Politics Economics

Answer 88

C - Personal Protective Equiptment

Question 89

The stethoscope is routinely placed over which artery for measuring blood pressure?

A - Axillary

B - Brachial

C - Radial

D - Subclavian

E - Ulnar

Answer 89

B - Brachial

Question 90

SBAR stands for which of the following?

A - Safe Bold Assertive Reflective

B - SEW score Blood pressure Allergies Respiration rate

C - Situation Background Assessment Recommendation

D - Situation Briefing Analysis Registration

E - Symptoms Background Assessment Refinement

Answer 90

C - Situation Bcakground Assessment Recommendation

Question 91

Which disposal route should be used for drug vials with residual drug?

A - Black bag

B - Blue bag

C - Green bag

D - Red bag

E - Orange bag

F - Yellow bag

G - Yellow sharps bin with blue lid

H - Yellow sharps bin with red lid

Answer 91

G - Yellow sharps bin with blue lid

Yellow sharps blue lid = medications vials with residual medicine

Question 92

Which disposal route should be used for paper towels?

A - Black bag

B - Blue bag

C - Green bag

D - Red bag

E - Orange bag

F - Yellow bag

G - Yellow sharps bin with blue lid

H - Yellow sharps bin with red lid

Answer 92

A - Black bag

Black bag = Household waste

Question 93

Which disposal route should be used for disposable gloves?

A - Black bag

B - Blue bag

C - Green bag

D - Red bag

E - Orange bag

F - Yellow bag

G - Yellow sharps bin with blue lid

H - Yellow sharps bin with red lid

Answer 93

E - Orange bag

Orange bag - Clinical waste

Question 94

At which point in the assessment would blood sugar levels be measured?

A - A

B - B

C - C

D - D

E - E

Answer 94

D - D

A: Airway assessment

B: Breathing assessment

C: Circulation assessment

D: Disability assessment in which glucose monitoring is integral

E: Evidence, environment, exposure

Question 95

Human factors are often referred to as…

A - A framework for practice

B - Communication tools

C - Non-technical skills

D - Patient assessment tools

E - Technical skills

Answer 95

C - Non-technical skills

A: Human factors does not provide a framework

B: Communication is a recognised human factor but only one element of human factors

C: Correct - sometimes referred to as non-technical skills, human factors are the social and cognitive skills which support and underpin performance of physical and technical skills.

D: Human factors are not tools for patient assessment

E: Technical skills are general practical procedures.

Question 96

What does the acronym AMPLE stand for?

A - Agitated, Mood, Physical state, Level of activity & Evidence

B - Alert, Medication, Physical activity , Last ate or drank & Events prior to now

C - Alert, mobility, Past medical history, Life support & Examination

D - Allergies, Medication, Past medical History, Last ate or drank & Events prior to now

E - Allergies, mental state, Physical activity, Living conditions & Evidence

Answer 96

D - Allergies, Medication, Past medical History, Last ate or drank & Events prior to now

Question 97

Calculate the NEWS score for the following:

Mrs Brown is a 66 year old lady who has recently been admitted to the acute medical unit (AMU) due to an infective exacerbation of COPD. She is awake and chatty when you meet her. She is not on oxygen therapy. On checking her vital signs you find the following:

Respiratory Rate: 20

Heart Rate : 85

SpO2: 94%

Blood Pressure: 155/75

Temperature: 38.4o

A - 0

B - 1

C - 2

D - 3

E - 5

F - 7

G - 11

H - 14

Answer 97

B - 1

RESP Rate - 0

Heart Rate - 0

BP - 0

Temp - 1

SpO2 - 0 (patient known to have COPD therefore target range is 88-92%)

AVPU - 0

NEWS score = 1

Question 98

Calculate the NEWS score for the following:

Mr Jackson is an 88 year old man who was admitted to hospital for investigation of falls. He is awaiting a review from the care of the elderly team. You find him in a chair reading the newspaper. Respiratory Rate: 15

Heart Rate: 76

SpO2: 97% ( on air)

Blood Pressure: 180/80

Temperature: 36.8o

A - 0

B - 1

C - 2

D - 3

E - 5

F - 7

G - 11

H - 14

Answer 98

A - 0

Resp Rate - 0

Heart Rate - 0

Sp02 - 0

BP - 0

Temp - 0

AVPU - 0

NEWS score = 0

Question 99

Calculate the NEWS score for the following:

Mr MacDonald is a 32 year old farmer admitted following a road traffic collision. He is currently unconscious and unresponsive in the emergency department being assessed by the trauma team. His vital signs are:

Respiratory Rate: 26

Heart Rate: 96

SpO2: 93% on 15l/min of oxygen via a reservoir mask

Blood Pressure: 90/45

Temperature: 37.6o

A - 0

B - 1

C - 2

D - 3

E - 5

F - 7

G - 11

H - 14

Answer 99

H - 14

Resp rate - 3

Heart rate - 1

Sp02 - 2

O2 therapy - 2

BP - 3

Temp - 0

AVPU - 3

NEWS score = 14

Question 100

The picture below is of a Gram stain of an organism grown from a patient with a urinary tract infection.

The organism was later identified as Escherichia coli, to which genus does it belong?

A - Gram negative bacilli

B - Coliform

C - Enterobacteriaceae

D - Exotoxin

E - Escherichia

F - Gram negative cocci

G - Gram positive bacilli

H - Gram positive cocci

I - Coli

J - Endotoxin

Answer 100

E - Escherichia

They belong to the genus Escherichia (Escherichia is the genus name, coli is the species name)

Question 101

The picture below is of a Gram stain of an organism grown from a patient with a urinary tract infection.

The organism is likely to produce?

A - Gram negative bacilli

B - Coliform

C - Enterobacteriaceae

D - Exotoxin

E - Escherichia

F - Gram negative cocci

G - Gram positive bacilli

H - Gram positive cocci

I - Coli

J - Endotoxin

Answer 101

J - Endotoxin

Gram negative bacilli produce endotoxin, which is derived from the Gram negative cell wall

Question 102

The picture below is of a Gram stain of an organism grown from a patient with a urinary tract infection.

The Gram stain of this organism is best described as …

A - Gram negative bacilli

B - Coliform

C - Enterobacteriaceae

D - Exotoxin

E - Escherichia

F - Gram negative cocci

G - Gram positive bacilli

H - Gram positive cocci

I - Coli

J - Endotoxin

Answer 102

A - Gram negative bacilli

These are rod­shaped organisms (bacilli) and stain pink/red with Gram stain­ Gram negative bacilli

Question 103

The picture below is of a microscopic view of the Gram stain of a bacterium grown from a wound swab:

The Gram stain of this organism is best described as…

A - Gram positive bacilli

B - Gram positive cocci

C - Endotoxin

D - Gram negative bacilli

E - Diphtheroid baccillus

F - Staphylococcus

G - Exotoxin

H - Gram negative cocci

I - Streptococcus

J -Neisseria

Answer 103

B - Gram positive cocci

These are round bacteria (cocci) staining blue/purple, i.e Gram positive cocci

Question 104

The picture below is of a microscopic view of the Gram stain of a bacterium grown from a wound swab:

To which genus does this organism belong?

A - Gram positive bacilli

B - Gram positive cocci

C - Endotoxin

D - Gram negative bacilli

E - Diphtheroid baccillus

F - Staphylococcus

G - Exotoxin

H - Gram negative cocci

I - Streptococcus

J -Neisseria

Answer 104

F - Staphylococcus

The cocci are arranged in grape­like clusters, so are likely to be Staphylococci

Question 105

The picture below is of a microscopic view of the Gram stain of a bacterium grown from a wound swab:

The organism is likely to produce …

A - Gram positive bacilli

B - Gram positive cocci

C - Endotoxin

D - Gram negative bacilli

E - Diphtheroid baccillus

F - Staphylococcus

G - Exotoxin

H - Gram negative cocci

I - Streptococcus

J -Neisseria

Answer 105

G - Exotoxin

Gram positive organisms produce exotoxins (toxins exported from the bacterial cell)

Question 106

Which term in a pathology report would warrent the most urgent management?

A - Hyperplasia

B - Dysplasia

C - Metaplasia

D - Aplasia

E - Neoplasia

Answer 106

C - Dysplasia

Dysplasia refers to disordered growth. The cells have begun to accumulate genetic damage and have taken steps towards becoming cancer.

Question 107

A breast cancer patient is found to have an epidermal growth factor receptor mutation. They will

A - have a better prognosis

B - have cheaper treatment

C - recieve trastuzamab

D - recieve imatinib

E - will pass an inherited cancer onto their daughters

Answer 107

C - Recieve trastuzamab

This relates to the EGHR pathway. Remember that Her2 is a type of EGFR and the target of herceptin. Herceptin is a trade name and the drug is called trastuzamab.

There is controversy about how much the drugs cost - they are very expensive. Breaset cancers with EGFR mutations typically have a worse prognosis. Whilst trastuzamab is a good drug you would therefore rather not need it because it means you have a nastier tumour.

Question 108

Cancer is more likely in people with…

A - acquired immunodeficiency syndrome

B - a heroin addiction

C - a low BMI

D - high blood pressure

E - diabetes

F - a history of tuberculosis

Answer 108

A - acquired immunodeficiency syndrome

This is a case of exclusion. Human papilloma virus can cause cancer. Patients that have AIDs are more likely to contract infections many of which can cause cancer. Diabetes can be associated can be associated with obesity which carries an increased risk of malignancy but diabetes itself does not.

Question 109

A pathology report reveals cells with a high n:c ratio, nuclear pleomorphism, coarse chromatin and prominent nuclei with irregular nuclear contours. The process is likely to be…

A - hyperplastic

B - inflammatory

C - degenerate

D - malignant

E - metaplastic

Answer 109

D - malignant

These are all features of malignancy. Hyperplasia and metaplasia refers to mature cells with no genetic abnormalities and normal development. There are no irregularitief from cell to cell.

The image encompasses all the features of malignancy. You can’t tell what the cell of origin is and we would therefore call these cells poorly differentiated. There are large cells. There are calls with little cytoplasm (high n:c ratio). The nuclei are dark (hyperchromatic). There is great variation in size and shape (pleomorphism). The nuclei are atypical (asymmetrical and irregular contours). Mitoses are present, some of which are abnormal.

Question 110

A tumour with a high grade has…

A - spread locally

B - spread to distant sites

C - looks like its cell of origin

D - poor differentiation

E - has grown quickly

Answer 110

D - poor differentiation

We can’t tell what the cell of origin is so we would call this poorly differentiated and therefore of a high grade. Tumour stage on the other hand refers to hor far the tumour has spread. This is generally done using the TNM classiciation (Tumour, Nodes, Metastases). Local spread is covered un “T”. Distant spread refers to nodal spread and distant metastes. Neither tumour stage or grade tell us about how quickly the tumour has grown. However, in general high stage and high grade tumours tend to be faster growing. Growth of tumours depends on a large number of other factors including the tumours blood supply.

Question 111

From the list below select the ONE BEST answer about blood pressure

A - Is the inward hydrostatic pressure exerted by blood in blood vessel walls

B - systolic arterial blood pressure is “the pressure exerted by blood in all peripheral vasculature when the heart contracts”

C - Mean arterial blood pressure is the average of systolic and diastolic arterial pressures

D - Pulse pressure is the difference between systolic arterial and diastolic arterial blood pressures

E - Clinic blood pressure of 128/82 mmHg is hypertension

Answer 111

D - Pulse pressure is the difference between systolic arterial and diastolic arterial blood pressures

Blood pressure is “the outwards (hydrostatic) pressure exerted by the blood on blood vessel walls”

In clinical practice we often measure the Systemic Arterial Blood Pressure and express it as “Systolic” and “Diastolic” blood pressures.

Systemic Systolic Arterial Blood Pressure: “is the pressure exerted by the blood on the walls of the aorta and systemic arteries when the heart contracts”: Systolic Pressure is normally <140 mm Hg under resting conditions.

Systemic Diastolic Arterial Blood Pressure: “is the pressure exerted by the blood on the walls of the aorta and systemic arteries when the heart relaxes”: normally <90 mm Hg

Question 114

From the list select the ONE BEST answer about short-term (moment-to-moment) control of arterial blood pressure

A - Is achieved via positive feedback mechanisms

B - Involves control of blood volume via hormones

C - Effectors are heart and blood vessels

D - Receptors are in the hypothalmus

E - control centre is in the hypothalmus

Answer 114

C - Effectors are heart and blood vessels

Question 115

If the mean arterial blood pressure decreases…

A - Vagal parasympathetic activity to the heart increases

B - Sympathetic activity to the heart decreases

C - The veins dilate

D - Vasoconstriction is caused by increased sympathetic activity

E - Stroke volume increases via increased parasympathetic activity to the heart

Answer 115

D - Vasoconstriction is caused by increased sympathetic activity

Question 116

A fit and healthy 24 year old butcher is boning a leg of lamb with a sharp knife. The knife slips and he sustains a deep laceration to his left groin. There is a large amount of bleeding as he cut a major vessel in his left groin. His colleague applies pressure to the area with a clean cloth and calls for an ambulance.

He feels dizzy and slightly breathless. Why is this?

Answer 116

Dizzy - Low arterial blood pressure as a result of blood loss - brain not getting normal perfusion and oxygenation. This can progress to confusion, lethargy and lodd of consciousness with more blood loss

Breathless - Body trying to supply more oxygen to tissues

Question 117

A fit and healthy 24 year old butcher is boning a leg of lamb with a sharp knife. The knife slips and he sustains a deep laceration to his left groin. There is a large amount of bleeding as he cut a major vessel in his left groin. His colleague applies pressure to the area with a clean cloth and calls for an ambulance.

Examination: he looks pale. His skin feels cool and clammy.

Why is that?

Answer 117

Arterial blood pressure decreases as a result of blood loss, low arterial blood pressure detected by baroreceptors, resulting in sympathetic stimulation and peripheral vasoconstriction. This helps raise systemic vascular resistance (SVR) and hence fight the drop in blood pressure.

Question 118

A fit and healthy 24 year old butcher is boning a leg of lamb with a sharp knife. The knife slips and he sustains a deep laceration to his left groin. There is a large amount of bleeding as he cut a major vessel in his left groin. His colleague applies pressure to the area with a clean cloth and calls for an ambulance.

Pulse: 120beats/min regular, weak.

Comment on the pulse? Which underlying mechanisms cause this?

Answer 118

Pulse is rapid (tachycardia) and weak.

Arterial blood pressure decreases as a result of blood loss, low arterial blood pressure detected by baroreceptors, resulting in increased sympathetic and decreased parasympathetic activity to the heart - both of these increase heart rate. The pulse is weak due to loss of blood volume resulting in low stroke volume.

Question 119

From the list below select the ONE BEST answer abount body temperature

A - The body thermostat is in the thalamus

B - Increased body temperature results in vasoconstriction of skin arterioles

C - Muscle tone is increased by warmth

D - In fever, a cold response raises the body temperature to a new set point

E - Sweating is controlled by the parasympathetic nervous system

Answer 119

D - In fever, a cold response raises the body temperature to a new set point

Question 120

Calculate the equilibrium potential for potassium (EK) across a membrane perfectly selective for that ion using values for [K+]o and [K+]i of 7 and 140 mM, respectively

Answer 120

Answer: -79.4 mV

Question 121

Calculate the equilibrium potential for sodium (ENa) across a membrane perfectly selective for that ion using values for [Na+]o and [Na+]i of 125 and 15 mM, respectively.

Answer 121

Answer: 56.2 mV​

Question 122

Calculate the equilibrium potential for chloride (ECl) across a membrane perfectly selective for that ion using values for [Cl-]o and [Cl-]i of 135 and 8 mM, respectively

Answer 122

Answer: -74.9 mV

Question 123

Calculate the equilibrium potential for calcium (ECa) across a membrane perfectly selective for that ion using values for [Ca2+]o and [Ca2+]i of 1.2 and 0.0002 mM, respectively

Answer 123

Answer: 115.2 mV

Question 124

Using the above values for [Na+]o, [K+]o, [Na+]i and [K+]i,, employ the simplified GHK equation to estimate the potential across a membrane permeable only to those ions, neglecting any other influences. Assume PK/PNa = 20.

Answer 124

Answer: -62.6 mV

Question 125

What is the extent of ionization (as a percentage of total drug) of aspirin (a weak acid with a pKa of 3.5) in acidic urine at pH 6.0?

Answer 125

Answer: 99.7% (approx.)

Question 126

What is the extent of ionization of morphine (a weak base with a pKa of 8.0) in cerebrospinal fluid at pH 7.3?

Answer 126

Answer: 83.4% (approx.)

Question 127

Drug X, in normal dosage, shows simple first-order elimination kinetics with a half life (t½) of approximately 2 hours. If given intravenously as a bolus at dose of 200 mg, what would be the amount that remains in the body after 5 hours?

Answer 127

Answer: 35.3 mg (approx.)

Question 128

For drug X at Cp = 325 mg per litre with a Cl of 5 ml per minute, what is the rate of elimination (in units of mg min-1)?

Answer 128

Answer: 1.625 mg min-1

Question 129

A tranquilizer with first-order elimination kinetics has a half life (t½) of 30 min. If its tranquilizing action terminates when the amount of drug in the body falls to 12.5 mg, what would be its duration of action when given at a dose of (a) 100 mg and (b) 200 mg? What is your conclusion about the relationship between drug dose and duration of drug action?

Answer 129

Numerical answer: (a) 90 min, (b) 120 min

Question 130

Drug X has an apparent volume of distribution (Vd) of 30 litres. What loading dose should be given as an intravenous bolus to attain a plasma concentration (Cp) of 0.5 mg per litre?

Answer 130

Answer: 15 mg

Question 131

Drug X given as an intravenous bolus at a dose of 30 mg has an initial plasma concentration (Cp) of 1.5 mg per litre. What is the apparent volume of distribution (Vd) of the drug?

Answer 131

Answer: 20

Question 132

A chemical reactin for which the associated enthalpy change is positive:

A - cannot occur spontaneously

B - may occur spontaneously if coupled to a reaction in which the enthalpy change is negative and of greater magnitude

C - raises the temperature of the surroundings

D - will inevitably occur spontaneously

Answer 132

B - may occur spontaneously if coupled to a reaction in which the enthalpy change is negative and of greater magnitude

Question 133

A chemical reaction for which the association free energy chnage is large and negative:

A - cannot occur spontaneously

B - is likely to be irreversible in the cell

C - will inevitably occur spontaneously

D - will occur very rapidly

Answer 133

B - is likely to be irreversible in the cell

Question 134

Which one of the following statements about ATP is correct?

A - ATP can diffuse through cell membranes

B - ATP is considered a low energy phosphate compound

C - ATP is present at high concentrations in the cell

D - Hydrolysis of ATP is a storngly exergonic reaction

Answer 134

C - ATP is present at high concentrations in the cell

Question 135

Which of the following statements best describes how a reaction is likely to behave if it has a large, negative value for G?

A - The reaction will be at equiilibrium

B - The reaction is likely to happen to a small extent, with only a small amount of product formed

C - The reaction will happen to a moderate extent, with about as much product being formed as reactant being left

D - The reaction is likely to happen to a large extent, with large amounts of product formed

Answer 135

D - The reaction is likely to happen to a large extent, with large amounts of product formed

Question 136

At Keg the value of the change in free energy for a chemical reaction is:

A - zero

B - greater or less than zero but remains at a stable value

C - does not chnage with respect to energy transfer from coupled reactions

D - The point at which the concentration of reactants and products are equal

Answer 136

A - zero

Question 137

What is a polar molecule?

A - A molecule with no charge

B - A molecule with opposite charges at opposite ends

C - A molecule with identical charges at opposite ends

D - Molecule with an unequal number of protons and electrons

Answer 137

B - A molecule with opposite charges at opposite ends

Question 138

How do water molecules arrange around ions?

A - The more negative atoms attach to positive ions

B - The more positive atoms attach to negative ions

C - Water forms a hydration shell

D - All of these answers are true

Answer 138

D - All of these answers are true

Question 139

Which is TRUE regarding the structure of hydrogen bonds?

A - Hydrogen bonds can only arise from the covalent interaction between oxygen and hydrogen atoms

B - It is only the hydrogen atoms of a water molecule which interact with polar molecules

C - Hydrogen bonds involve a linea arrangement of one hydrogen atom between two electronegative atoms

D - Hydrogen bonds are angles at 104.3˚

Answer 139

C - Hydrogen bonds involve a linea arrangement of one hydrogen atom between two electronegative atoms

Question 140

Which one of the following statements about amino acids is correct?

A - Amino acids are classified according to the structures and properties of their side chains

B - Amino acids are uncharged at neutral pH

C - Amino acids in protains are mainly in the D-configuration

D - Twenty four amino acids are commonly used in protein synthesis

Answer 140

A - Amino acids are classified according to the structures and properties of their side chains

Question 141

All amino acids contain an alpha carbon bonded to the following structures:

A - an amino group (-NH2), a carboxyl group (-COOH), a hydrogen (-H), a side chain (-R)

B - an amide group (-CONH2), a carboxyl group (-COOH), a hydrogen (-H), a side chain (-R)

C - a amino group (-NH2), a carboxyl group (-COOH), a hydroxyl group (-OH), a side chain (-R)

D - an amide group (-CONH2), a hydrogen (-H), a side chain (-R)

Answer 141

A - an amino group (-NH2), a carboxyl group (-COOH), a hydrogen (-H), a side chain (-R)

Question 142

Which of the follwing statements is true about a peptide bond (RCONHR’)?

A - It is non planar

B - It is capable of forming a hydrogen bond

C - Electron resonance between amino and carbonyl groups creates a partial double bond

D - The cis configuration is favoured over the trans configuration

Answer 142

C - Electron resonance between amino and carbonyl groups creates a partial double bond

Question 143

During the formation of the peptide bond which of the follwoing takes place?

A - a-amino group of one amino acid acts as a nucleophile to displace the hydroxyl group of another amino acid forming a peptide bond

B - Hydrogen atom is lost from its carboxyl group of one amino acid and a hydroxyl group is lost from its amino group of another amino acid

C - Hydroxy group is lost from its carboxyl group of one amino acid and a hydroxyl group is lost from its amino group of another amino acid

D - Hydrogen atom is lost from its carboxyl group of one amino acid and a hydrogen atom is lost from its amino group of another amino acid

Answer 143

A - a-amino group of one amino acid acts as a nucleophile to displace the hydroxyl group of another amino acid forming a peptide bond

Question 144

Compare solution A with pH = 4 to solution B with pH = 6

A - The concentration of [H⁺] in solution A is twice that in solution B

B - Solution A has greater buffering capacity than solution B

C - The concentration of [H⁺] in solution A is 100 times that in solution B

D - The hydroxide concentrations are equal in the two solutions since pH only measures the concentration of H⁺

Answer 144

C - The concentration of [H⁺] in solution A is 100 times that in solution B

Question 145

Two weak acids, A and B, have pKa values of 4 and 6, respectively. Which statement is true?

A - Acid A dissociates to a greater extent in water than acid B

B - For solutions of equal concentration, acid B will have a lower pH

C - B is the conjugate base of A

D - Acid A contains more ionizing groups than acid B

E - The equivalence point of acid A is higher than that of acid B

Answer 145

A - Acid A dissociates to a greater extent in water than acid B

Question 146

A solution of HCl with a concentration of 4x10^-4 mol.L^-1 has a pH of which of the following?

A - 2.67

B - 3.21

C - 3.40

D - 4.00

E - 4.31

Answer 146

C - 3.40

pH -= -log[H⁺]

[H⁺] = 0.0004M

-log[0.0004] = 3.39794 or 3.40

Question 147

A buffer solution contains ethanoic acid and its conjugate base; the pKa of ethanoic acid is 4.74. At what pH does the solution buffer?

A - 3.0

B - 4.0

C - 5.0

D - 6.0

Answer 147

C - 5.0

Question 148

A strong acid will display a larger Ka but smaller pKa value compared to a weak acid. True or false?

Answer 148

True

Srtong acids favour [H+]. [A-} so ratio to [HA] gives a larger value. Since pKa = - logKa, pKa values become smaller with increasing acid strength.

Question 149

An amino acid can act as an acid or a base. True or false?

Answer 149

True

The carboxyl group donates [H+] = acid

The amino group can accept [H+] and so can act as a base

Question 150

Which 3 statements about zwitterionic amino acids are correct?

A - Reductable atoms in the amino acid side group side group enable switterions to alter charge deoending upon prevailing pH

B - Zwitterionsare dipolar molecules which act as buffers of acids and bases

C - Charge differences at amino and carboxyl residues of zwitterions balance each other such that the molecules is non-polar

D - Zwitterion ion charge may be positive or negative depending upon prevailing pH

E - Zwitterions display a single pKa

F - The overall charge of a zwitterion is neutral at a pH equivalent to the isoelectric point, pl

Answer 150

B - Zwitterionsare dipolar molecules which act as buffers of acids and bases

D - Zwitterion ion charge may be positive or negative depending upon prevailing pH

F - The overall charge of a zwitterion is neutral at a pH equivalent to the isoelectric point, pl

Question 151

Which type of bonding is responsible for the secondary structure of proteins?

A - Disulphide bridges between cysteine residues

B - Hydrogen bonding between the C=O and N-H groups of peptide bonds

C - Peptide bonds between amino acids

D - Salt bridges between charged side chains of amino acids

Answer 151

B - Hydrogen bonding between the C=O and N-H groups of peptide bonds

Question 152

Which term below best defines the ‘quaternary structure’ of a protein?

A - The arrangement of two or more polypeptide subunits into a single functional complex

B - The folding of the polypeptide backbone in three-dimensional space

C - The interaction of amino acid side chains

D - The sequence of amino acids in a polypeptide chain

Answer 152

A - The arrangement of two or more polypeptide subunits into a single functional complex

Question 153

Which of the follwoing statements about collagen is correct?

A - Collagen contains a high proportion of hydroxylated proline residues

B - Collagen is a globular, intracellular protain

C - Post-translational modification of collagen involves vitamine A

D - The structure of collagen consists of a superhelix of three a helices twisted together

Answer 153

A - Collagen contains a high proportion of hydroxylated proline residues

Question 154

Which of the follwoing amino acids is mostly likely to disrupt an alpha helix?

A - Proline

B - Leucine

C - Glycine

D - Valine

Answer 154

A - Proline

Question 155

Which of the folwing most accurately describes how secondary structures in proteins are stablised?

A - Through ionic bonds operating between oppositely charged amino acid side chains

B - Through covalent bonds joining different parts of the peptide backbone

C - Thorugh hydrogen bonds between different amino acid side chains

D - Through hydrogen bonds joining different parts of the peptide backbone

Answer 155

D - Through hydrogen bonds joining different parts of the peptide backbone

Question 156

Which of the follwing pairs of amino acids might contibute to protain confomation by forming electrostatic interactions?

A - Glycine and leucine

B - Glutamate and lysine

C - Phenylalanine and tyrosine

D - Lysine and arginine

Answer 156

B - Glutamate and lysine

Question 157

Which amino acid can form disulphide bonds?

A - Glycine

B - Proline

C - Glutamate

D - Cysteine

Answer 157

D - Cysteine

Question 158

Which of the following best describes a protein domain?

A - The a-helical portion of a protein

B - A discrete region of polypeptide chain that has folded into a self-contaned three dimensional structure

C - The β-pleated sheet portion of a protain

D - A feature that rarely occurs in globular proteins

Answer 158

B - A discrete region of polypeptide chain that has folded into a self-contaned three dimensional structure

Question 159

Which of the following statements correctly describes the effect of glutamic acid to valine substitution upon the quaternary structure of hemoglobin?

A - The heme domain is acidified causing iron to move from its normal Fe(II) to Fe (III)

B - Hydrophobic interactions between hemoglobin tetramers cause aggregation

C - Charge differences result in α and β subunit disaggregation

D - Electron transfer between α and β subunits and the heme domain no longer occurs

Answer 159

B - Hydrophobic interactions between hemoglobin tetramers cause aggregation

Question 160

Which one is TRUE about nucleic acids?

A - New nucleotides are added to the 5’ end of growing nucleic acids

B - New nucleotides are added to the 3’ end of growing nucleic acids

C - New nucleosides are added to the 3’ end of gwoing nucleic acids

Answer 160

B - New nucleotides are added to the 3’ end of growing nucleic acids

Question 161

Which one is FALSE about DNA replication?

A - Replication is semi-conservative

B - Replication is catalysed by DNA polymerases

C - Replication is discontinuous

D - Replication does not require RNA molecules

Answer 161

D - Replication does not require RNA molecules

Question 162

Which strand is the coding strand?

A - A

B - B

Answer 162

B - B

Question 163

Which one is FALSE about specific transcription factors?

A - They contain one of several DNA binding domains

B - They bind DNA at specific regulatory sequences

C - They require additional factors to bind DNA

D - They regulate transcription of several genes stimultaneously

Answer 163

C - They require additional factors to bind DNA

Question 164

Introns are…

A - Non-coding sequences

B - Coding sequences

C - Present in mRNA

D - Binding sites for transcription factors

Answer 164

A - Non-coding sequences

Question 165

Which one is FALSE about splicing?

A - It occurs in the cytoplasm

B - It occurs in the nucleus

C - It removes introns from the transcript , leaving only exons

D - It requires a complex machinery

Answer 165

A - It occurs in the cytoplasm

Question 166

Which one is TRUE about translation in eukaryotic cells?

A - It only requires energy for elongation

B - It only requires special protain factors for termination

C - Proteins are synthesised from the N-terminus to the C-terminus

D - Translation can occur while transcription is still ongoing

Answer 166

C - Proteins are synthesised from the N-terminus to the C-terminus

Question 167

Translation in eukaryotic cells…

A - Can start at several different start codons

B - Starts with the first start codon from the 5’ end of the RNA

C - Proceeds from the 3’ end to the 5’ end of the mRNA

D - Occurs in the nucleus

Answer 167

B - Starts with the first start codon from the 5’ end of the RNA

Question 168

Which one is FALSE about the genetic code?

A - It is nearly universal

B - It is ambiguous

C - It is degenrate

D - It is based on triplets of nucleotides

Answer 168

B - It is ambiguous

Question 169

Which one is not a type of mutation?

A - Interverion

B - Nonsense

C - Translation

D - Missense

E - Deletion

F - Point

Answer 169

C - Translation

Question 170

Nonsence mutations…

A - Introduce a wrong amino acid

B - Introduce a stop codon

C - Remove one or two base pairs

D - Have no negative concequence

Answer 170

B - Introduce a stop codon

Question 171

Which one is TRUE about buffers?

A - Weak acids are not good bufers

B - A buffer is a solution to control the pH of a reaction mixture

C - A buffer is a solution which does not chnage its pH

Answer 171

B - A buffer is a solution to control the pH of a reaction mixture

Question 172

Which one is FALSE about the Henderson-Hasselbalch equation?

A - It connects the acid dissociation constant of a weak acid to the pH of a solution containing this acid

B - It allows us to calculate the pH of a solution containing a weak acid

C - It allows us to estimate at which pH a weak acid is a good buffer

D - It shows that the pH of a solution containing a weak acid is directly proportional to the concentration of the acid

Answer 172

D - It shows that the pH of a solution containing a weak acid is directly proportional to the concentration of the acid

Question 173

Which one is FALSE about amino acids?

A - All amino acids have an alpha carbon, a carboxyl group and an amino group

B - All amino acids have D- abd L-isomers

C - Polar amino acids are soluble in water

Answer 173

B - All amino acids have D- abd L-isomers

Question 174

Which one is FALSE about the acid-base properties of amino acids?

A - The zwitterion form has both positive and negative charges

B - In solution of low pH amino acids are positivly charges

C - In solutions of high pH amino acids are positivly charges

D - The side groups of amino acids can contain titratable groups

Answer 174

C - In solutions of high pH amino acids are positivly charges

Question 175

Which of the follwoing interactions are not involved in stabalising a protain’s three dimensional sturcture?

A - Hydrophobic interactions

B - Electrostatic interactions

C - Covalent interactions

D - Hydrogen bonds

E - None of them

Answer 175

D - Hydrogen bonds

Question 176

Which one of these interactions in a protein can be disrupted by extremes of pH?

A - Hydrophobic interactions

B - Electrostatic interactions

C - Covalent interactions

D - Disulphide bonds

Answer 176

A - Hydrophobic interactions