Formative questions

Question 1

Examining a histological section, a pathologist sees a cell undergoing mitosis. The chromosomes are moving towards opposite poles of the cell and there are no nuclear membranes. Which phase of mitosis is this?

Answer 1

Anaphase

Question 2

Which is the last phase of mitosis?

Answer 2

Cytokinesis

Question 3

During mitosis, chromosomes attach themselves to microtubules that propagate from centrosomes.
What are these microtubules made of?

Answer 3

Tubulin

Question 4

A 33-year-old woman presents with an unusual rash which the dermatologist biopsies. A dashing pathologist examines a section of skin under the microscope. He observes some cells which he believes are mast cells.
What stain, which turns the granules in mast cells purple, can our hero use to confirm his hypothesis?

Answer 4

Toluidine Blue. Toluidine blue is metachromatic (it changes colour). Toluidine blue stains the granules in mast cells purple. It can also be used to stain nuclei and some tissue components e.g. collagen blue

Question 5

An astute University of Sheffield medical student examines a section of liver tissue and notices some brown pigment within the liver cells. She wonders if the patient could have haemochromatosis (a form of iron overload). What stain, which turns iron-containing pigment blue, would confirm her hypothesis?

Answer 5

Perl’s Stain. The Perl’s stain uses a Prussian blue reaction that demonstrates ferric iron. Sections are treated with dilute hydrochloric acid to unmask ferric irons in the hydroxide form (Fe(OH)3) and are then treated with potassium ferrocyanide to produce an insoluble blue compound, ferric ferrocyanide (Prussian blue).

Question 6

A tumour cell in the synthesis phase of the cell cycle begins the process of DNA replication.
What substances splits the two DNA strands apart??

Answer 6

Helicase

Question 7

While analysing human genetic material, a geneticist observes that sample A contains single-stranded nucleic acids, and sample B contains double-stranded nucleic acids.
What substance will be found only in sample A and not in sample B?

Answer 7

Uracil

Question 8

A forensic scientist is presented with a minute quantity of cellular material from a crime scene. The sample contains only a few cells. In order to produce a sample that is large enough for analysis, he adds the components of DNA to the sample. Assuming that the DNA strands have been split apart, which other substance must be added to catalyse the amplification of the sample?

Answer 8

DNA polymerase

Question 9

What cells kill bacteria using the respiratory burst?

Answer 9

Neutrophils. Neutrophils make use of oxygen free radicals to kill phagocytosed bacteria using the respiratory burst.

Question 10

Which of the listed substances is not a component of cell membranes or the receptors associated with them?

1. Cholesterol
2. Dihydrogen oxide
3. Glycolipids
4. Lipoproteins
5. Phospholipids

Answer 10

Dihydrogen oxide. Cell membranes are lipid bilayers in which there are embedded lipoproteins and glycoproteins. They do not contain water (dihydrogen monoxide).

Question 11

Which enzyme catalyses the reaction of 1,3-biphophoglycerate to 3-phosphoglycerate?

Answer 11

Phosphoglycerate kinase. Phosphoglycerate kinase transfers a phosphate group from 1,3-bisphosphoglycerate to ADP for form ATP and 3-phosphoglycerate.

Question 12

The average 70kg male has a store of approximately 350g of this substance, which can be used as an energy source. What is the energy source?

Answer 12

Glycogen. The average 70kg human stores approximately 350g of glycogen - 200g in the liver and 150g in skeletal muscles. We have much larger stores of protein (6kg) and triacylglycerol (15kg) available as a fuel source.

Question 13

How are steriod hormones transported in the blood?

Answer 13

Steroid hormones are lipid soluable, have no storage pool, are synthesised from cholesterol and are transported in plasma bound to carrier proteins. They bind to intracellular receptors.

Question 14

Do epiblasts in a 3 week embryo become ectoderm?

Answer 14

YES!

Question 15

What supplies the cardiac muscle?

Answer 15

Left and right coronary arteries

Question 16

When does blood flow to the heart occur?

Answer 16

Mainly during diastole

Question 17

What does the left coronary artery split into?

Answer 17

The left anterior descending and the circumflex artery

Question 18

Compared to other veins, the oxygen saturation in coronary venous blood is very low (often O2 saturation of only 35%). Why is this?

Answer 18

Because oxygen extraction by the heart muscle is very high

Question 19

What does the right coronary artery supply?

Answer 19

The inferior surface (underside) of the heart

Question 20

What is responsible for synthesising coagulation factors and fibrinogen?

Answer 20

The liver

Question 21

This is/these are the precursor(s) for an enzyme that lyses clots:

Answer 21

Plasminogen

Question 22

These constitute the coagulation cascade:

Answer 22

A series of proteolytic enzymes that circulate in the blood in an inactive form. When activated they create thrombin.

Question 23

This cleaves fibrinogen into fibrin:

Answer 23

Thrombin

Question 24

This is/these are released upon cell activation and contain a high concentration of a molecule that acts as an agonist at the platelet P2Y12 receptor:

Answer 24

Platelet dense granules

Question 25

What is responsible for the apex beat normally palpated in the left 5th intercostal space and midclavicular line?

Answer 25

Left ventricle

Question 26

What prevents backflow of blood into the left atrium during ventricular systole?

Answer 26

Mitral valve

Question 27

Carries oxygenated blood from the lungs to the left side of the heart?

Answer 27

Pulmonary vein

Question 28

Maintains the systemic diastolic blood pressure by preventing backflow of blood into the heart during diastole?

Answer 28

Aortic valve

Question 29

Prevents high pressures developing in the jugular veins during ventricular systole.

Answer 29

Tricuspid valve

Question 30

Carries deoxygenated blood back to the right atrium?

Answer 30

Inferior vena cava

Question 31

This represents ventricular repolarisation on an ECG?

Answer 31

T wave

Question 32

The normal duration for this is 120 to 200 msec (0.12-0.2 sec) on an ECG?

Answer 32

PR interval

Question 33

Assess(es) the electrical activity within the lateral myocardial territory on an ECG?

Answer 33

Leads 1, aVL, V5, V6

Question 34

This (these) yields complexes that are normally inverted compared to the anterior and inferior leads on an ECG

Answer 34

Lead aVR

Question 35

This may be abnormally elevated during acute injury/infarction of a substantial myocardial territory on an ECG?

Answer 35

ST segment

Question 36

This represents atrial depolarisation on an ECG?

Answer 36

P wave

Question 37

This represents ventricular depolarization and should be less than 120 msecs in duration?

Answer 37

QRS complex

Question 38

Which of the following statements about defaecation is TRUE?

1. Distension of the rectum causes contraction of the internal anal sphincter
2. Distension of the rectum causes relaxation of the external anal sphincter
3. Levator ani relaxes during defaecation
4. The internal anal sphincter is under voluntary control
5. The urge to defaecate is signalled by the propulsion of faeces into the sigmoid colon

Answer 38

3. The levator ani relaxes during defaecation. Levator ani draws the rectum forwards and upwards maintaining continence, it is relaxed during defaecation. Pelvic floor muscles (levator ani, puborectalis) regulate fecal retention and defaecation Puborectalis suspends the rectosigmoid and provides continence Continence also depends on internal and external anal sphincters

Question 39

Which of the following statements about intestinal mucosa is TRUE?

1. Appendices epiploca are present on the jejunum
2. Brunner’s glands are present in the sigmoid colon
3. Ascending colonic mucosa contains Paneth cells
4. Caecal mucosa has few plicae circulares
5. Goblet cells stain strongly with H+E

Answer 39

4. Caecal mucosa has few plicae circulares. The mucosa of the various parts of the large intestine and rectum are identical. It lacks villi and Paneth cells (these are features of small intestinal mucosa). Brunner’s glands are found only in the duodenum. Peyer’s patches are found in the submucosa, and may extend into the mucosa. Goblet cells stain strongly with PAS but have clear cytoplasm on H+E. Stem cells are present in the crypts of Lieberkuhn, not the tips of the villi. Plicae circulares are prominent in the small intestine and infrequent in the large intestine

Question 40

Which of the following statements about hepatic protein metabolism is TRUE?

1. 20-25% of liberated amino acids are re-utilized
2. Adults turn over 10% of their total body protein each day
3. Patients recovering from surgery go into a phase of positive nitrogen balance
4. Protein kinases convert ADP + protein into phosphoprotein + ATP
5. Skeletal muscle experiences a low rate of protein turnover during starvation

Answer 40

3. Patients recovering from surgery go into a phase of positive nitrogen balance. Pregnancy, body building (with anabolic steroids), obesity and recovery from illness/surgery all result in a net gain in protein (and hence nitrogen) in the body. Malnutrition is associated with negative nitrogen balance.

Question 41

Which of the following statements about the urea cycle is TRUE?

1. Arginine is converted to citrulline and urea
2. One turn of the cycle consumes 6 ATP equivalents.
3. The cycle converts citrulline and ammonia to arginine
4. The cycle converts ornithine and ammonia to arginine
5. The cycle is down-regulated in starvation.

Answer 41

3. The cycle converts citrulline and ammonia to arginine. Arginine either from the diet or protein breakdown, is cleaved by arginase generating urea and ornithine. In subsequent reactions a new urea is built on the ornithine (from ammonia and CO2) making citrulline. This, in turn, is reconfigured into arginine. The enzymes responsible for this are found partly in the mitochondria and partly in the cytosol (like glutaminase/glutamine synthase). The reactions of one turn of the cycle consume 3 ATP equivalents and a total of 4 high energy nucleotide PO4= .

Question 42

Which of the following statements is TRUE?

1. Auerbach’s plexus is a network of arteries and veins
2. Interstitial cells of Cajal are readily seen in H+E stained sections
3. Interstitial cells of Cajal have no known function
4. Meissner’s plexus lies within the mucosa of the small intestine
5. Meissner’s plexus lies between the circular and longitudinal layers of the muscularis propria

Answer 42

4. Meissner’s plexus lies within the mucosa of the small intestine. Meissner’s plexus lies in the submucosa, while Auerbach’s plexus lies between the circular and longitudinal muscle cells of the muscularis propria. Both are nerve plexuses. Interstitial cells of Cajal are hard to see on H+E (but can be stained for with C-KIT immunohistochemistry) and are the pacemaker cells of the gut. Interstitial cells of Cajal give rise to gastrointestinal stromal tumours (GISTS).

Question 43

Which of the following statements about the pancreas is TRUE?

1. Pancreas divisum occurs in 50% of the general population
2. It receives its main blood supply from the superior mesenteric artery
3. The head of the pancreas is attached to the spleen
4. The tail may be crushed against the vertebrae by blunt force trauma to the abdomen
5. Venous drainage is mainly to the splenic vein

Answer 43

5. Venous drainage is mainly to the splenic vein. The body (and perhaps part of the head) of the pancreas may be crushed against the vertebrae. The pancreas receives its blood supply from the coeliac trunk, and venous drainage is to the splenic vein. Pancreas divisum is a congenital anomaly in which the dorsal and ventral pancreas in the embryo fail to fuse. It affects only about 5% of the general population.

Question 44

Which of the following statements about the pancreas is TRUE?

1. Amylase is secreted as an inactive precursor
2. Approx 7 litres of pancreatic juice are secreted per day
3. As the rate of secretion rises the bicarbonate concentration falls
4. Blood draining the pancreas has a relatively low pH
5. Centroacinar cells secrete amylase

Answer 44

4. Blood draining the pancreas has a relatively low pH. The pancreas produces approx 1 litre of an an enzyme-rich alkaline secretion per day. The acinar cells secrete enzymes and the centroacinar cells secrete a bicarbonate-rich fluid. These secretions pass into the duodenum (not the blood - it is the islet cells that secrete directly into the blood stream). Overall one bicarbonate ion is secreted into the pancreatic juice in exchange for one hydrogen ion into the blood. Therefore the blood draining the pancreas has a relatively low pH and this helps to neutralize the so-called ‘alkaline tide’ of blood draining the stomach following a meal because the reverse is happening in the stomach.

Question 45

Which of the following statements about the biliary system is TRUE?

1. Bile duct pressure is equivalent to systemic arterial pressure
2. Bile pigments emulsify fats
3. Bile salts are reduced by gut bacteria to produce urobilinogen
4. Bile salts can be absorbed in the jejunum
5. Blood from the gallbladder drains into the cystic vein

Answer 45

4. Bile salts can be absorbed in the jejunum. The normal adult has a pool of 3g of bile salts. These are reabsorbed from the gut (an entero-hepatic circulation). While most are reabsorbed in the terminal ileum, absorption begins in the jejunum. Bile salts (not bile pigments) can emulsify fats. They are anionic detergents. Bile is concentrated in the gallbladder, which while it receives its blood supply from the cystic artery, does not have a discrete venous drainage. (Blood drains into the liver). Bile duct pressure is normally low - 6-10mmHg.

Question 46

Please select the ONLY statement which is true.

1. Blood from the cerebral circulation drains into sinuses that are formed between the dura and arachnoid
2. The cavernous sinus does not receive blood from the orbit
3. Cerebrospinal fluid is re-adsorbed into the inferior sagittal sinus
4. The straight sinus receives venous blood from the inferior sagittal sinus and the great cerebral vein
5. Venous blood from the cerebral circulation exits the cranium via the jugular foramina and is returned to the heart via the external jugular veins

Answer 46

4. The straight sinus receives venous blood from the inferior sagittal sinus and the great cerebral vein

Question 47

Please select the ONLY statement which is true. Arterial supply of the brain:

1. The majority of the blood supply comes from the two vertebral arteries
2. The left anterior cerebral artery carries blood to the motor cortex of the right leg
3. The basilar artery carries blood to the basal ganglia
4. An embolus of the internal carotid artery will infarct the cerebellum
5. The posterior cerebral arteries are direct branches from the internal carotid arteries

Answer 47

2. The left anterior cerebral artery carries blood to the motor cortex of the right leg

Question 48

Please select the ONLY statement which is true. The circle of Willis:

1. Is formed by vessels of the anterior circulation of the brain only
2. The middle cerebral artery is a direct continuation of the internal carotid artery
3. Supplies blood to the cerebellum
4. Is an uncommon site for Berry aneurysms to occur
5. The communicating arteries act as a functional anastamoses between the left and right cerebral circulations

Answer 48

2. The middle cerebral artery is a direct continuation of the internal carotid artery

Question 49

Please select the ONLY statement which is true.

1. Wernicke’s area is located in the frontal lobe and Broca’s area is situated in the temporal lobe
2. A stroke affecting the circulation to the occipital lobe may result in memory problems
3. A stroke affecting the internal capsule is usually embolic
4. Strokes affecting one side of the motor or sensory cortex will result in a contra-lateral neurological deficit
5. A right hemisphere stroke is likely (i.e. > 50%) to cause dysphasia in a left handed individual

Answer 49

4. Strokes affecting one side of the motor or sensory cortex will result in a contra-lateral neurological deficit

Question 50

The primary motor cortex:

1. Occupies the post-central gyrus
2. Is supplied by the middle cerebral artery only
3. The largest muscles of the body are given the largest area of the motor cortex
4. Is also known as Brodmann’s Area 44
5. Muscles of the lower limbs are represented medially, whereas the muscles of the face are represented laterally

Answer 50

5. Muscles of the lower limbs are represented medially, whereas the muscles of the face are represented laterally

Question 51

The primary motor cortex:

1. The corticospinal tract originates from the ventrolateral (motor) thalamic nucleus
2. The corticospinal tracts pass between the basal ganglia and thalamus to enter the cerebral peduncle
3. The lateral corticospinal tract decussates at the level of the pons
4. A stroke affecting the motor cortex will result in a greater neurological deficit than the same sized stroke affecting the internal capsule
5. The motor cortex produces an abnormal rhythmical output in Parkinson’s disease

Answer 51

2. The corticospinal tracts pass between the basal ganglia and thalamus to enter the cerebral peduncle

Question 52

Descending pathways:

1. Upper motor neurons innervate muscles directly
2. Axons of the upper motor neurons are mainly located in the lateral white matter of the spinal cord
3. The cell bodies of lower motor neurones are located in the lateral horn of the spinal cord
   A motor unit is defined as a particular muscle and all the motor neurons which are required to innervate it
   Lower motor neurons leave the spinal cord posteriorly

Answer 52

2. Axons of the upper motor neurons are mainly located in the lateral white matter of the spinal cord

Question 53

The muscle spindle:

1. Muscle spindles are found in skeletal muscles. They are composed of intrafusal muscle fibres whereas skeletal muscle is composed of extrafusal muscle
2. The middle one-third of the spindle is associated with type 1a efferent sensory nerves
3. The two ends of the muscle spindle are non contractile while the central portion is contractile
4. Alpha motor neurons innervate the muscle fibres of the spindle
5. Gamma motor neurons innervate extrafusal muscle fibres

Answer 53

1. Muscle spindles are found in skeletal muscles. They are composed of intrafusal muscle fibres whereas skeletal muscle is composed of extrafusal muscle

Question 54

The muscle spindle:

1. Muscle spindles only detect muscle contraction
2. Muscle spindle activity contributes to the change in muscle resistance to stretch following a stroke
3. The startle reflex is an example of a stretch reflex
4. Muscle spindles detect changes in muscle tension
5. Muscle spindles are only involved in conscious aspects of proprioception

Answer 54

2. Muscle spindle activity contributes to the change in muscle resistance to stretch following a stroke

Question 55

The golgi tendon organ:

1. Golgi tendon organs are situated within smooth and cardiac muscle
2. The sensory fibres leading from the Golgi tendon organ to the spinal cord are 1a afferent fibres
3. They measure the force developed by the muscle and any resultant change in length
4. Afferent impulses from the Golgi tendon organ result in the inhibition of alpha motor neurons of the muscle fibres associated with the activated Golgi tendon organ to regulate muscle tension at a normal range and also to protect the muscle from overload
5. They are only inhibitors of the skeletal alpha motor neurone

Answer 55

4. Afferent impulses from the Golgi tendon organ result in the inhibition of alpha motor neurons of the muscle fibres associated with the activated Golgi tendon organ to regulate muscle tension at a normal range and also to protect the muscle from overload

Question 56

The golgi tendon organ:

1. Golgi tendon organ produces a single output irrespective of the level of muscle tension
2. They are involved in the inverse myotatic reflex (clasp knife reflex)
3. They contain muscle fibres to alter tension
4. Golgi tendon organs possess faster afferent fibres than muscle spindles
5. Golgi tendon organ activity results in the inhibition of the antagonist muscles to the ones in which they are found

Answer 56

2. They are involved in the inverse myotatic reflex (clasp knife reflex)

Question 57

Skin receptors:

1. Large receptive fields are found in areas like the fingers where we have greatest tactile sensitivity
2. Some cutaneous receptors are phasic in response and others tonic
3. Tactile receptors act as transducers but do not show summation
4. Skin receptors are specialised neurone cell bodies
5. Receptive field sizes are not relevant to understanding the behaviourial specialisations of humans

Answer 57

2. Some cutaneous receptors are phasic in response and others tonic

Question 58

The dorsal column-medial lemniscus column:

1. Is a system characterised by slow conduction velocities
2. Is a tract which carries information regarding pain sensation from the skin to higher centres
3. Lies in the anterior white matter of the spinal cord
4. Fibres in the dorsal columns are arranged topographically
5. Decussation of the fibres of the DCML system occurs in the spinal cord as the tract ascends to the brain stem

Answer 58

4. Fibres in the dorsal columns are arranged topographically

Question 59

The plasma membrane of neurones:

1. When in the resting state contains more open sodium (Na+) channels than open potassium (K+) channels
2. Is an excitable membrane
3. Is always associated with myelin sheaths
4. Contains very few active transport pumps
5. Has a positive resting potential inside with respect to the outside

Answer 59

2. Is an excitable membrane

Question 60

The corticospinal tract:

1. The lateral corticospinal tract supplies the contralateral side of the body
2. The lateral corticospinal tract carries fibres controlling muscles involved in balance and posture
3. The anterior corticospinal tract mainly supplies the contralateral side of the body
4. The anterior corticospinal tract is located antero-lateral to the anterior horn of grey matter
5. The lateral corticospinal tract contains fewer fibres than the anterior corticospinal tract

Answer 60

3. The anterior corticospinal tract mainly supplies the contralateral side of the body

Question 61

Descending tracts:

1. The tectospinal tract is involved in maintaining our upright posture by its effects on the muscles of the lower limb
2. The vestibulospinal tract consists of crossed fibres and controls head turning in response to visual stimuli.
3. The reticulospinal tract originates from cells found in the pons and the medulla and may act to facilitate or inhibit the activity of various ascending tracts
4. The rubrospinal tract is an uncrossed system which functions as a highly skilled version of the lateral corticospinal tract
5. The reticulospinal tract acts as a pathway for the hypothalamus to control autonomic spinal outflow

Answer 61

5. The reticulospinal tract acts as a pathway for the hypothalamus to control autonomic spinal outflow

Question 62

The resting membrane potential of neurons:

1. Has a value which is positive inside with respect to the outside
2. Sodium/potassium pumps found in the membrane creates a concentration gradient of ions which is required to maintain the resting potential
3. Is mostly governed by the permeability of the membrane to sodium ions
4. Maintaining the concentration gradients requires transportation of potassium ions out of the cell and sodium ions into the cell
5. Is produced mostly as a result of sodium (Na+) diffusing out of the neuron

Answer 62

2. Sodium/potassium pumps found in the membrane creates a concentration gradient of ions which is required to maintain the resting potential

Question 63

An action potential:

1. Occurs as sodium channels open in the membrane resulting in the membrane potential briefly becoming more positive on the inside with respect to the outside
2. The size of an action potential depends on the threshold level reached
3. During repolarisation (phase from peak back to resting potential) voltage gated sodium channels in the membrane open
4. Results in a change in the membrane potential from approx. -30mv to approx. +10mv
5. At +30mv the voltage gated Na+ channels close in response to the changed membrane potential

Answer 63

1. Occurs as sodium channels open in the membrane resulting in the membrane potential briefly becoming more positive on the inside with respect to the outside

Question 64

Refractory periods:

1. The relative refractory period is a time during which a second stimulus, needs to be stronger to produce a second action potential
2. Is a phenomenom which lasts between 50-100ms
3. The relative refractory period is followed by the absolute refractory period
4. Facilitates propagation of an action potential in either direction
5. Has no effect on the frequency of action potentials capable of being produced in a neuron

Answer 64

1. The relative refractory period is a time during which a second stimulus, needs to be stronger to produce a second action potential

Question 65

Synapses:

1. A synaptic cleft is a feature found in all types of synapses
2. The majority of synapses are electrical synapses
3. Chemical synapses are always inhibitory
4. Allows summation of input potentials to occur
5. Electrical synapses employ the use of neurotransmitters to evoke an action potential in the next neuron

Answer 65

4. Allows summation of input potentials to occur

Question 66

Chemical synapses:

1. Is the site where all neurotransmitters are synthesised
2. Each neuron forms only one synapse with any other neuron
3. Possess specific receptors on the post-synaptic membrane
4. The closure of calcium channels ultimately results in the release of neurotransmitters from the cell
5. Neurotransmitters travel from the post-synaptic membrane to the pre-synaptic cell via the process of diffusion

Answer 66

3. Possess specific receptors on the post-synaptic membrane

Question 67

CN 1:

1. Has both afferent and efferent components
2. If damaged, will result in anosmia on the contralateral side
3. Enters the cranial cavity via small holes in the cribriform plate of the ethmoid bone
4. Is commonly damaged in fractures to the posterior cranial fossa
5. Patients who have sustained damage to this nerve may complain of loss of sensation in their nasal septum

Answer 67

3. Enters the cranial cavity via small holes in the cribriform plate of the ethmoid bone

Question 68

CN 2:

1. Can be tested in the unconscious patient by observing pupillary constriction in response to light
2. Enters the skull via the superior orbital fissure
3. First joins the opposite cranial nerve II within the optic radiation
4. Its fibres are closely related to the medial geniculate body
5. A lesion affecting the left optic tract will result in total blindness in the left eye

Answer 68

1. Can be tested in the unconscious patient by observing pupillary constriction in response to light

Question 69

CN 3, 4 and 6:

1. All take a course which runs through the inferior petrosal sinus
2. CN III carries parasympathetic fibres
3. Damage of CN III will lead to ptosis of the eyelid on the opposite side
4. Damage to CN VI will result in the inability to adduct the affected eye
5. A person with CN IV damage will complain of double vision as they look up (e.g. when walking up a flight of stairs)

Answer 69

2. CN III carries parasympathetic fibres

Question 70

CN 5:

1. Is a purely sensory nerve
2. Passes through foramen spinosum to supply sensation to the face
3. Damage will result in the loss of the corneal reflex on the affected side
4. Carries taste information from the posterior 1/3 of the tongue
5. Supplies the sub-mandibular salivary gland

Answer 70

3. Damage will result in the loss of the corneal reflex on the affected side

Question 71

CN 7:

1. An upper motor neurone lesion will cause drooping of the eyelid on the affected side
2. Runs a course which is closely related to the middle ear
3. Conveys sensation from the posterior 1/3rd of the tongue
4. Supplies the sweat glands of the face
5. Has its nucleus in the tectum of the pons

Answer 71

2. Runs a course which is closely related to the middle ear

Question 72

CN 8:

1. Is concerned only with hearing
2. Exits the cranial cavity via foramen lacerum
3. When diseased may cause rapid eye movements; nystagmus
4. With complete damage, when a tuning fork is placed in the middle of the forehead, the sound is heard best on the same side as the damage
5. A tumour of the nerve may cause paralysis of the muscles of facial sensation

Answer 72

3. When diseased may cause rapid eye movements; nystagmus

Question 73

CN 9:

1. Is purely a sensory nerve
2. Carries parasympathetic fibres to the parotid glands
3. Supplies the muscles of the tongue and pharynx
4. Leaves the cranium through foramen ovale
5. Is closely associated with the hypoglossal nerve

Answer 73

2. Carries parasympathetic fibres to the parotid glands

Question 74

CN 10:

1. Is made up of both sensory and motor components 2. Carries sympathetic fibres to the heart, lungs and bowel
2. Leaves the brain at the level of the pons
3. Has a branch which supplies the stylopharyngeus muscle
4. Causes increased heart rate and blood pressure when stimulated

Answer 74

1. Is made up of both sensory and motor components

Question 75

CN 11:

1. Carries parasympathetic fibres
2. Has a single root
3. Runs in close proximity to the vertebral artery
4. Exits the cranial cavity via the foramen magnum alongside the spinal cord
5. Injury to the nerve causes paralysis of the sternocleidomastoid and superior trapezius muscles on the same side as the lesion

Answer 75

5. Injury to the nerve causes paralysis of the sternocleidomastoid and superior trapezius muscles on the same side as the lesion

Question 76

CN 12:

1. Contains both motor and sensory components
2. Supplies only the intrinsic muscles of the tongue
3. Leaves the cranial cavity via the jugular foramen
4. Its nerve cell bodies are located within the medulla 5. Damage to the nerve will cause paralysis of the contralateral half of the tongue

Answer 76

4. Its nerve cell bodies are located within the medulla

Question 77

The spinothalamic tract:

1. Is a tract which carries proprioceptive, vibration and two-point discrimination modalities to the somatosensory cortex.
2. Conveys nociceptive information to the ipsilateral thalamus
3. Is found in the dorsomedial white matter of the spinal cord
4. Conveys nociceptive information contralaterally up the spinal cord.
5. After they decussate the fibres of the spinothalamic tract project directly into the neocortex.

Answer 77

4. Conveys nociceptive information contralaterally up the spinal cord.

Question 78

Following traumatic hemisection of the spinal cord on the right at the level of C7, the patient presents with which ONE of the following signs and symptoms.

1. Loss of two point discrimination appreciation below the level of the lesion on the left.
2. A right-sided hemiparesis.
3. Lower motor neuron paralysis at the level of C7 on the ipsilateral side.
4. Loss of pain and temperature appreciation at all segments below the level of the lesion on the right.
5. Loss of proprioceptive information conveyed to the contralateral cerebellum

Answer 78

3. Lower motor neuron paralysis at the level of C7 on the ipsilateral side.

Question 79

The middle ear:

1. The middle ear is a fluid filled chamber which communicates with the nasal cavity.
2. Conductive deafness is a reduction in the mechanical transmission of sound waves to the round window.
3. Sensation is via the VIIIth CN
4. The chain of three ossicles have cartilaginous joints between them
5. The stiffness of the ossicullar chain can be modified by two muscles of the middle ear.

Answer 79

5. The stiffness of the ossicullar chain can be modified by two muscles of the middle ear.

Question 80

The cochlea:

1. The cochlea is the organ of hearing and balance.
2. The scala vestibuli is continuous with the scala tympani via the semicircular canals .
3. The Organ of Corti is a specialised structure which rests on the basilar membrane.
4. The cochlea coils 5 times around the modiolus (the central axis of the spiral).
5. Sound waves enter via the round window

Answer 80

3. The Organ of Corti is a specialised structure which rests on the basilar membrane.

Question 81

The cochlea:

1. The basilar membrane is narrower at its apex and wider at its base.
2. Some antibiotics can damage the stereocilia of the hair cells.
3. The base of the basilar membrane is sensitive to low frequencies whereas the apex is sensitive to high frequencies.
4. There can be 4-5 rows of inner hair cells while there is only a single row of outer hair cells.
5. During aging low tone deafness occurs first

Answer 81

2. Some antibiotics can damage the stereocilia of the hair cells.

Question 82

The semi-circular canals:

1. Function to detect the position of the head with respect to gravity and linear acceleration
2. There are 3 in total on each side, which are arranged parallel to each other in the horizontal plane
3. Damage to the canals of one side result in a nystagmus with the slow phase away from the damaged side and the rapid reset towards it.
4. The semi-circular canals in the left ear affect the movement of the left eye only.
5. Pouring ice cold water in the external auditory meatus can cause convection currents in the semicircular canals and nystagmus.

Answer 82

5. Pouring ice cold water in the external auditory meatus can cause convection currents in the semicircular canals and nystagmus.

Question 83

The utricle and the saccule:

1. Signals both the position of the head with respect to gravity and rotational acceleration.
2. Stereocilia of the utricles and saccules project into the basilar membrane.
3. Only signal rotational acceleration of the head.
4. Are filled with lymph
5. Signal the position of the head at rest (i.e. when no movement is occurring).

Answer 83

5. Signal the position of the head at rest (i.e. when no movement is occurring).

Question 84

The cerebellum:

1. Mossy Fibres are axons which are derived only from the inferior olivary nucleus.
2. Climbing fibres are thought to have a function in determining which ‘motor program’ is used for different motor movements
3. The output neurons from the cerebellar cortex are known as granule cells and are excitatory in nature.
4. Each Purkinje Fibre receives input from many thousands of parallel fibres .
5. Feedback information, from the cerebellum to the cerebral cortex, travels via the medial and lateral geniculate thalamic nuclei

Answer 84

4. Each Purkinje Fibre receives input from many thousands of parallel fibres .

Question 85

The cerebellum:

1. Is involved in the initiation of co-ordinated movement.
2. Is thought to have a part in the learning and storage of motor skills.
3. Principally receives information from the olfactory system.
4. Is part of the direct pathway producing nystagmus.
5. A lesion of the left lobe will result in a decomposition of movement on the right hand side of the body.

Answer 85

2. Is thought to have a part in the learning and storage of motor skills.

Question 86

Olfaction and gustation:

1. Olfaction and gustation are represented contralaterally in areas including the post-central gyrus (tongue region) and insular cortex.
2. Afferents from olfactory receptors directly project to the primary gustatory cortex (anterior insula and inferior frontal gyrus)
3. A single glomerulus in the olfactory bulb takes input from many receptors corresponding to a specific part of the nasal lining
4. The same mechanism is involved in the transduction of different taste molecules
5. Taste sensation is carried by CNs VII , IX and X

Answer 86

5. Taste sensation is carried by CNs VII , IX and X