Wrong Formative True/False Questions Flashcards
Hydrophilic molecules are water soluble.
True
True - the term hydrophilic means “water loving” – they can dissolve readily in water by forming hydrogen bonds. Such substances travel easily in the blood.
Pathological processes are all naturally-occurring disorders that cause disease
False
Pathological processes can also arise unnaturally, for example following traumatic injury or iatrogenic (caused by healthcare) harm.
Plasma pH is proportional to carbonic acid concentration divided by bicarbonate ion concentration
False
Plasma pH is proportional to bicarbonate ion concentration divided by carbonic acid concentration (or CO2 levels as remember we can substitute CO2 for carbonic acid and get the same effect in terms of movement of pH)
In a structured patient history, “ICE” stands for “Introduction, Consent and Explanation”
False
The acronym “ICE” is commonly used to mean “Ideas, Concerns and Expectations”, and is a helpful summary of what you should cover when gathering information about your patient’s perspective.
Intracellular fluid volume can be measured directly.
False
We can only directly measure the volume of fluid compartments of which plasma is a component because we only have access to the plasma (via veins) to inject the marker and sample the diluter marker after equilibration. Plasma is not a component of intracellular fluid (ICF). However ICF is a component of total body water (TBW) so if we measure TBW using heavy water, and we measure ECF using radiolabelled Na+ (remember plasma is a component of both ECF and TBW) we can calculate ICF indirectly by subtracting ECF from TBW.
Radiolabelled albumin can be used to measure extracellular fluid volume.
False
Albumin is a plasma protein and is thus confined to the plasma compartment. It cannot move into the interstitial fluid compartment. Because extracellular fluid (ECF) is a product of plasma volume and interstitial fluid (ISF) volume you need a marker that can move freely between plasma and ISF, but not intracellular fluid, in order to be able to measure ECF volume. Sucrose or radiolabelled Na+ would do the job nicely.
The rough endoplasmic reticulum modifies protein after it has been synthesised.
True
The rough endoplasmic reticulum modifies protein after it has been synthesised.
Bicarbonate ions and phosphate ions are the major buffer systems in the body
False
These two ions form the main buffering agents that help maintain body fluid pH at 7.4.
The phospholipid bilayer forms a barrier to polar molecules.
True
Lipophilic molecules can dissolve straight through the phospholipid bilayer, polar (hydrophilic) molecules must generally travel through protein channels or with the aid of transport proteins.
Erythropoietin is primarily produced by the liver
False.
Produced by the kidneys (85% and 15% in liver).,`
In terms of the electrochemical gradient, the electrical gradient and concentration gradient of a substance are always going in the same direction, but with different magnitudes.
False
the electrical gradient and concentration gradient for any substance may be in the same direction or they may oppose each other. Potassium, for instance, has a concentration gradient favouring outward movement but because the inside of the cell is negative compared to the outside, the electrical gradient favours inward movement of the positively charged potassium ion. However, because the concentration is much greater than the electrical gradient, potassium moves out of a cell when the potassium ion channels open.
It is possible for a solution to be both hyperosmotic and hypotonic
True
Osmolarity describes the number of total solutes in a solution without describing whether they can cross the cell membrane or not. Tonicity describes the number of solutes in a solution than cannot readily cross the membrane (non-penetrating particles). A solution may be hyperosmotic if, for example, it contains a higher level of urea than normal plasma, but if at the same time it contains a lower level of sodium than normal plasma it would also be hypotonic.
The cell membrane is freely permeable to ions.
False
while ions can cross the cell membrane they need help from protein ion channels to do so at any useful speed. These ion channels tightly regulate the movement of ions across the membrane and it is this tight regulation that maintains the concentration gradients and marked differential distribution of ions either side of the cell membrane, or in other words the significant difference in composition between the ICF and ECF.
Glucose crosses the cell membrane by active transport.
False
glucose uses transporter proteins but it enters cells down a concentration gradient so active transport (using energy to drive the movement of a substance against a concentration gradient) is not required.
Erythroblasts are immature red blood cells found in the circulation
False
erythroblasts are immature red blood cells found in the bone marrow. Once released into the circulation they are called reticulocytes. Reticulocytes circulate and mature over the next 24 hours to become fully mature red blood cells (erythrocytes)
The citrate shuttle moves acetyl CoA from the mitochondria to the cytosol to make fatty acids.
True
This step is necessary to transfer the acetyl CoA from the mitochondrial matrix where it is made to the cytosol for fatty acid synthesis. This only happens where the citrate levels in the mitochondria are high and fatty acyl molecules are low in concentration.
Acetoacetate is the only ketone body detected by a urine dipstick test.
True
The test used to detect ketonuria only picks up acetoacetate not Beta-hydroxybutarate. (remember this by a-pee-to-acetate!!) Acetone is usually exhaled. Beta-hydroxybutyrate can be detected in blood using a separate test.
Glycogen in a cell is osmotically inactive
True
Conjugated proteins are those which are composed of two or more separate amino-acid chains.
False
A conjugated protein is one that functions by being attached to another non-protein group, eg glycoproteins, lipoproteins and metalloproteins.
Acetyl-CoA is the gateway for food molecules into the citric acid cycle.
True
Amino acids, fatty acids and glucose (via pyruvate) all enter the citric acid cycle via acetyl-CoA
Glucose molecules are removed from glycogen in the form of glucose 6-phosphate.
False
Glucose monomers are removed from the non-reducing ends as glucose 1-phosphate
Uncoupling agents inhibit the passage of electrons along the terminal respiratory system.
False
Uncoupling agents still allow the passage of electrons along the terminal respiratory system, but they render the inner mitochondrial membrane permeable to protons so the proton gradient cannot be generated. O2 is still reduced to H2O, but no ATP is made and the excess energy is released as heat. You should have heard of brown fat and of malignant hyperthermia in this context.
Glycogen is a polymer with many reducing ends.
False
Glycogen is a polymer with many non-reducing ends.
A patient with type 2 diabetes has made an appointment with their GP to discuss a new drug they have read about online that has shown to reverse diabetes. This is an example of a personal factor influencing a consultation T/F?
True
The R-group of an aliphatic amino-acid contains a hydrocarbon ring.
False
The R-group of an aliphatic amino-acid consists of a hydrocarbon chain, eg alanine or leucine. The R-group of an aromatic amino-acid contains a hydrocarbon ring, eg phenylalanine or tyrosine.
All antiviral drugs act by inhibiting viral nucleic acid synthesis.
False
many do. However antiviral drugs can act on any stage of the viral replication cycle, e.g. attachment, penetration, protein synthesis, viral budding, etc.
Viruses may replicate in soil and water.
False
Fimbriae are filaments on the bacterial cell surface that give it motility.
False
It’s flagella
Light microscopy can be used in the routine laboratory to screen faeces for the presence of viruses.
False
routine viral screening of faeces is through Polymerase Chain Reaction (PCR), looking for viral nucleic acids. Light microscopy can be used to detect larger pathogens, such as parasites.
Co-trimoxazole is combination of Teicoplanin and sulphamethoxazole.
False
False, it is a combination of trimethoprim and sulphamethoxazole
Malaria is never passed from human to human.
False
while the vast majority of malaria transmission is through mosquito vectors, it can rarely be spread human to human through blood transfusion, needle-sharing or organ transplantation.
Pasteurisation results in sterilisation of milk.
False
pasteurisation involves heating milk at a moderate temperature (around 60-70 degrees celsius) for a short length of time. This greatly reduces the number of pathogens, such that they are unlikely to cause disease, and increases shelf-life.
Sterilisation completely eliminates organisms, occurs at a much higher temperature (>100 degrees), and allows milk to be stored unrefrigerated (UHT milk).
Chlorination of drinking water prevents infections with all intestinal parasites.
False
an example of a parasite not killed by chlorination is Cryptosporidium.
Light microscopy can be used in the routine laboratory as a more sensitive detection method for bacteria than culture.
False
culture is a more sensitive detection method, as a much lower concentration of bacteria is required for a positive result.
Squamous metaplasia in the airways may be caused by cigarette smoking.
True
True - irritation from cigarette smoke may cause the pseudostratified columnar epithelium of the airways to take on a squamous cell morphology.
btw i got some of these right just thought i would add them in hehe
Malignant tumours are characterised by the presence of a capsule.
False - a fibrous capsule surrounding a tumour is likely to indicate that it is benign.
Nuclear pleomorphism in a tumour is evidence of malignancy.
True - loss of normal mitotic regulatory pathways leads to nuclear pleomorphism (nuclei of tumour cells all appear different).
Hepatitis B virus is associated with human tumours.
True - Hep B is associated with liver cancer.
Granulomatous inflammation of viral hepatitis.
False - granulomas are not a feature of viral hepatitis.
Malignant tumours are characterised by aberrant mitotic figures.
True - abnormal and uncontrolled mitosis is a feature of malignancy.
Cytological aberration is evidence of malignancy in a tumour.
True - the presence of abnormal cells (dysplasia) in a tumour is often an indicator of malignanc
Mast cells are actively phagocytic.
False - mast cells mediate inflammatory response in hypersensitivity by degranulation - release of pro-inflammatory chemicals. They are not phagocytes.
Wound contraction is due to Vitamin C.
False - Vitamin C plays an important role in collagen formation. Wound contraction is caused by fibroblasts and myofibroblasts.
All new drugs will undergo Phase 1 clinical trials
False – Phase 1 trials, where drugs are given to healthy volunteers, are bypassed for some drugs, such as cancer chemotherapy.
Drugs must have completed phase 4 clinical trials before they can be licensed for use.
False – phase 4 clinical trials happen after the drug has been released. This is the ongoing surveillance stage of trialling a new drug, where long-term effects can be studied.
If a drug undergoes extensive firstpass metabolism it will have a lower bioavailability.
True – first-pass metabolism refers to when drugs are metabolized (eg by the gut lumen, gut wall, liver, etc) before entering the systemic circulation.
Drugs applied to the skin will not have a systemic effect.
False – drugs given topically (eg. Steroids) will still be absorbed and may have a systemic effect. Drugs can also be applied as patches, where the intention is for systemic activity (eg. A contraceptive patch or a nicotine patch.)
In randomised controlled trials assessment is always carried out by blinded observers
False – some RCTs are single-blinded, meaning only the patient is blinded.
Gentamicin is lipid-soluble.
False – gentamicin is NOT lipid-soluble, and therefore cannot cross cell membranes, and is not absorbed. This is why it is generally given intravenously in clinical practice.
Sublingual administration avoids first-pass metabolism.
True – drugs (such as GTN) as absorbed directly from the oral mucosa into the systemic circulation, rather than undergoing first-pass metabolism in the gut.
