Foundations Of Health And Disease 2002/3

Front 1

Mark the following statements concerning an agonist true or false:
A) It always binds irreversibly to a receptor
B) It elicits a functional response proportional to the number of receptors occupied
C) It always has a higher affinity than an antagonist for a particular receptor
D) It can overcome the action of a competitive antagonist
E) It can cause the receptor to desensitise if bound for a prolonged period (In LAPT the statement is "It can cause a receptor to desensitise if the receptor is exposed to the agonist for a prolonged period".

Back 1

A) F
B) F
C) F
D) T
E) T

Front 2

Mark the following statements concerning competitive antagonists true or false:
A) They always bind covalently to receptors
B) They reduce the maximum response an agonist can elicit
C) They shift the agonist log-dose-response curve to the right without changing its slope
D) They have zero efficacy
E) They for a particular receptor all have the same pA2 (KB) value

Back 2

A) F
B) F
C) T
D) T
E) F

Front 3

Mark the following statements concerning drugs that bind to receptors true or false:
A) They are always agonists
B) They can show selectivity for one optical isomer
C) They have specific chemical structures
D) They act on only one class of receptor
E) They always trigger a cellular or physiological response

Back 3

A) F
B) T
C) T
D) F
E) F

Front 4

Mark the following true if they are are intracellular messengers or false if not:
A) Cyclic adenosine monophosphate
B) Inositol tetraphosphate
C) Cyclic guanosine monophosphate
D) Cyclic uridine monophosphate
E) Diacylglycerol.

Back 4

A) T
B) F
C) T
D) F
E) T

Front 5

Mark the following statements concerning drug receptors true or false:
A) A drug usually binds to only one receptor type
B) Cellular responses to receptors that are ion channels are usually fast
C) Cellular responses to receptors that are slow if the mode of action involves modification of DNA transcription
D) G-proteins amplify the effect of receptor stimulation
E) Receptors are continually being synthesised and destroyed by the cell

Back 5

A) F
B) T
C) T
D) T
E) T

Front 6

Mark the following statements concerning components of food and the body true of false:
A) Glycogen is a polymer of glucose that is found in plants.
B) The many dietary disaccharide in the UK is sucrose which contains both glucose and fructose.
C) Lactose, a disaccharide containing glucose and galactose, can be found in the circulation.
D) Some sugars are chemically bonded to proteins in cells.
E) Carbohydrates are the main storage form of energy in the human body.

Back 6

A) F
B) T
C) F
D) T
E) F

Front 7

Mark the following statements concerning body and dietary fats true or false:
A) The triacylglycerol content of the average lean male is close to 15% of body weight.
B) Fats containing saturated fatty acids are more likely to be liquids.
C) Cholesterol is an essential component of the body.
D) Trans fatty acids do not contain any double bonds.
E) ω3 Fatty acids are mainly found in fish oils.

Back 7

A) T
B) F
C) T
D) F
E) T

Front 8

Mark the following statements concerning phospholipids true or false:
A) They contain a glycerol backbone to which fatty acids are attached by ester bonds.
B) They contain a glycerol backbone to which a polar headgroup is attached via a phosphate group.
C) They contain fatty acids with long hydrocarbon chains which tend to reside within a hydrophobic environment
D) Trioleoylglycerol, the main constituent of olive oil, is an example of a phospholipid
E) Phosphatidylcholine, a major constituent of cell membranes, is a phospholipid

Back 8

A) T
B) T
C) T
D) F
E) T

Front 9

Mark the following statements about how the components of the plasmalemma are synthesized, transported and organized true or false:
A) Proteins are synthesized from individual amino acids at the rough endoplasmic reticulum
B) The insulin receptor is an example of an intrinsic membrane protein
C) Newly synthesized plasmalemmal proteins pass from the Golgi complex to the rough endoplasmic reticulum and then to the plasmalemma
D) A single integral protein of the plasmalemma will have some of its surface exposed to the cytosol and some of its surface exposed to the extracellular fluid
E) A single phospholipid molecule in the plasmalemma will have some of its surface exposed to the cytosol and some of its surface exposed to the extracellular fluid

Back 9

A) T
B) T
C) F
D) T
E) F

Front 10

Mark the following statements about membrane voltages true or false:
A) The inside of a mitochondrion is negative with respect to the cytosol
B) The cytosol of most cells is positive with respect to the extracellular fluid
C) If the extracellular concentration of potassium rises, with extracellular sodium falling by the same amount, the resting voltage of most cells will become more negative
D) If electron transport is blocked then the mitochondrial membrane potential will become more positive
E) Chloride ions are repelled out of cells by the negative resting voltage (although other forces may or may not oppose this electrical force)

Back 10

A) T
B) F
C) F
D) T
E) T

Front 11

Mark the following statements concerning the cytoskeleton true or false:
A) Actin filaments polymerize from G actin monomers using GTP as an energy source.
B) Actin filaments are organized by the centrosome.
C) Dynein is a motor protein associated with microtubules.
D) Kinesin is a motor protein associated with actin .
E) Lamins are a type of intermediate filament in the nucleus.

Back 11

A) F
B) F
C) T
D) F
E) T

Front 12

Mark the following statements concerning elastic arteries true or false:
A) They are typically small vessels located in the extremities
B) They lack an adventitia
C) They possess a tunica media with many concentric, fenestrated, elastic laminae
D) They possess a tunica media with smooth muscle fibres
E) They possess a series of valves throughout their length

Back 12

A) F
B) F
C) T
D) T
E) T

Front 13

Mark the following statements concerning fibroblasts true or false:
A) They are probably derived from embryonic mesenchyme cells
B) Collagen is synthesised intracellularly
C) They synthesise and secrete amorphous ground substances such as hyaluronic acid
D) They do not divide
E) They are phagocytic cells

Back 13

A) T
B) F
C) T
D) F
E) F

Front 14

Mark the following statements concerning connective tissue true or false:
A) Its only significant function is to provide mechanical support for other tissues
B) Muscle is a form of connective tissue
C) Fibroblasts, fat cells, white blood cells and mast cells are all constituents of connective tissue
D) Ground substance, which is highly, proteinaceous is the material in which the cells of connective tissue are embedded
E) In soft tissues the principal constituent of ground substance is hyaluronic acid

Back 14

A) F
B) T
C) T
D) F
E) T

Front 15

Mark the following statements concerning the role of ATP in enzyme-catalysed reactions true or false:
A) Endothermic reactions are commonly linked to the hydrolysis of ATP.
B) Anabolic (biosynthetic reactions) are commonly linked to the condensation of ADP and phosphate to form ATP.
C) ATPase catalyses the phosphorylation of ADP to ATP.
D) There is very much more ADP than ATP in the cell.
E) ATP is formed by the reduction of ADP.

Back 15

A) T
B) F
C) T
D) F
E) F

Front 16

Mark the following statements concerning free radicals and antioxidant nutrients true or false:
A) Free radicals may cause mutations by causing strand breaks in DNA.
B) Free radicals may be involved in the development of atherosclerosis because they cause oxidation of amino acids in plasma lipoproteins.
C) The production of oxygen radicals, and hence the risk of oxidative damage to plasma lipoproteins, is increased in infection.
D) Superoxide dismutase decreases the risk of radical damage to plasma lipoproteins because it catalyses the removal of the superoxide radical.
E) Protein-binding of transition metal ions decreases the production of potentially damaging oxygen radicals.

Back 16

A) T
B) T
C) T
D) T
E) T

Front 17

Mark the following statements concerning ways in which we can gather evidence linking diet and diseases of affluence true or false:
A) In a secular study people who have moved from one country to another are compared with their relatives at home and the native population of their country of adoption.
B) In a case-control study people with and without the disease of interest are matched for as many factors as possible, and their diets compared.
C) In a correlation study changes in diet are compared with disease incidence over a period of time in order to see what dietary factors might be associated with changes in disease incidence.
D) In a correlation study dietary patterns and disease incidence in different countries are compared in order to see what dietary factors might be associated with changes in disease incidence.
E) In an intervention study the effect of giving a nutritional supplement to one group of people is compared with a control group given a placebo.

Back 17

A) F
B) T
C) F
D) T
E) T

Front 18

The diagrams above show relative risk of mortality from all causes (on the left) and cardiovascular disease (on the right) among people who habitually consume different amounts of wine, beer or spirits each day. Mark the following statements true or false:
A) Wine drinking decreases death from cardiovascular disease.
B) Beer drinking decreases death from cardiovascular disease.
C) Beer drinking decreases all cause mortality.
D) Spirit drinking decreases death from cardiovascular disease.
E) Spirit drinking increases all cause mortality.

Back 18

A) T
B) T
C) F
D) F
E) F

Front 19

Mark the following statements concerning transport across cell membranes true or false:
A) Hydrophilic compounds generally enter cells by passive diffusion.
B) Facilitated (carrier-mediated) diffusion linked to phosphorylation of a substrate once it has entered a cell permits accumulation of a higher concentration of the substrate inside the cell than outside.
C) Net accumulation of hydrophobic compounds inside a cell, to a higher concentration that outside, can be achieved if there is an intracellular binding protein.
D) Facilitated (carrier-mediated) diffusion alone permits accumulation of a higher concentration of the substrate inside the cell than outside.
E) Active transport always results in a higher concentration of the substrate on one side of the cell membrane than the other.

Back 19

A) F
B) T
C) T
D) F
E) T

Front 20

Mark the following statements concerning enzymes true or false:
A) An enzyme catalyses a reaction by decreasing the activation energy.
B) An enzyme does not affect the position of the equilibrium of the reaction catalysed.
C) The active site of an enzyme consists of both a substrate binding site and a catalytic site.
D) The active site of an enzyme is made up from the side-chains of amino acids that may be some distance apart in the primary sequence.
E) The enzyme is unchanged at the end of the reaction.

Back 20

A) T
B) T
C) T
D) T
E) T

Front 21

Mark the following statements concerning the fed and fasting metabolic states true or false:
A) Fatty acids are synthesised in adipose tissue in the fed state.
B) Red blood cells can oxidise fatty acids in the fasting state.
C) There is an increase in metabolic rate in the fasting state.
D) Glucagon is secreted in response to a high concentration of glucose in the portal blood.
E) Proteins are catabolised and the amino acids used as metabolic fuel in the fasting state.

Back 21

A) T
B) F
C) F
D) F
E) T

Front 22

Mark the following statements concerning nucleic acids true or false:
A) In DNA the 3’ end of one strand is aligned next to the 5’ strand of the other.
B) In DNA a purine always pairs with another purine.
C) A genome is the information for synthesis of a protein.
D) A palindromic sequence of bases read from the 3’ end is complementary to the sequence read from the 5’ end.
E) Ignoring the cap on mRNA, the 3’ end of RNA has a free hydroxyl group at carbon 3 of ribose.

Back 22

A) T
B) F
C) F
D) T
E) T

Front 23

Mark the following statements concerning gene expression true or false:
A) During DNA replication cytosines are methylated only in areas in which they are methylated in the parent strand.
B) Even though a gene is not expressed in a particular cell, it is still present in the DNA.
C) Hormone receptor proteins can bind to the TATA box to regulate gene expression.
D) When a differentiated cell divides, the genes that have been switched off are now available for transcription.
E) The genes in a cell that are not expressed are known as introns.

Back 23

A) T
B) T
C) F
D) F
E) F

Front 24

Mark the following statements about stem cells in the skin true or false:
A) Stem cells in the skin are relatively undifferentiated.
B) Stem cells in the skin are pluripotent.
C) Stem cells are found in all layers of the epidermis.
D) When a stem cell in the skin divides, both daughter cells remain as stem cells.
E) Stem cells in the skin can divide without limit.

Back 24

A) T
B) F
C) F
D) F
E) T

Front 25

The following statements concern an experiment in which cells in culture were incubated with [3H]thymidine. Mark each statement true or false. If the percentage of mitotic cells in a culture is 5% and the percentage of cells that label with radioactive thymidine is 40%, this shows that:
A) 50% of the cells are progressing through the cell cycle.
B) 40% of the cells are progressing through the cell cycle.
C) 35% of the cells never divide.
D) The cells spend 40% of their time in S phase.
E) The cells spend 5% of their time in mitosis.

Back 25

A) F
B) F
C) F
D) T
E) T

Front 26

Mark the following statements about the cell cycle true or false:
A) Interphase in proliferating cells is divided in three distinct phases.
B) The third cell division in the sea urchin embryo produces uneven sized blastomeres.
C) M phase is usually followed by G2 phase.
D) Only cells is S phase incorporate tritium labelled thymidine into their DNA.
E) Go phase refers to postmitotic cells that cannot divide again.

Back 26

A) T
B) F
C) F
D) T
E) F

Front 27

Mark the following statements concerning spermatozoa true or false
A) When a spermatozoon contacts the plasma membrane of the oocyte, enzymes in its acrosome are released extracellularly
B) Sperm in the female genital tract remain able to fertilize an oocyte for at least a day after ejaculation, and sometimes as long as three days.
C) Behind the DNA-bearing head of a spermatozoon, mitochondria are strung out all along the tail to provide energy for flagellar motion
D) The human spermatozoon has a head concerning 90 μm long and a tail 400-500 μm long
E) Once the plasma membranes of sperm and oocyte make direct contact, the oocyte engulfs the entire sperm by endocytosis

Back 27

A) F
B) T
C) F
D) F
E) F

Front 28

Mark the following statements concerning protein structure and function true or false:
A) Compounds other than amino acids may be involved in forming the catalytic site of an enzyme.
B) The active site of an enzyme is made up from the side-chains of amino acids that may be some distance apart in the primary sequence.
C) Disulphide bonds are important in the primary structure of many proteins.
D) Glycine is every third residue in the collagen polypeptide because it is the only amino acid whose side chain can be accommodated within the triple helix.
E) Denaturation is the result of breaking the hydrogen bonds that stabilise secondary structure.

Back 28

A) T
B) T
C) F
D) T
E) T

Front 29

A random sample of 100 middle-aged men was used to investigate their systolic blood pressure. The data were found to follow a normal distribution with a mean of 145 mm Hg and a standard deviation of 21 mm Hg. The standard error was also calculated. Mark the following statements true or false:
A) A 95% confidence interval for the mean systolic blood pressure could be calculated as (145 – standard deviation, 145 + standard deviation).
B) The standard error is a measure of the variability of observations within the sample.
C) The sum of the systolic blood pressures for all the men would be 14500 mmHg.
D) The median of the values for the observations is 145 mmHg.
E) The standard error can be calculated from the standard deviation and the sample size.

Back 29

A) F
B) F
C) T
D) T
E) T

Front 30

The standard normal distribution has a mean of 0 and a standard deviation of 1. Mark the following statements true or false:
A) The shape of a normal curve which has a mean of 2 and a standard deviation of 1 would be exactly the same shape as the standard normal distribution.
B) Data of a continuous nature will always be normally distributed.
C) A plot of this distribution would be symmetrical about the value 1.
D) 95% of the observations lie below the value 1.96.
E) 50% of the observations lie above the mean.
End

Back 30

A) T
B) F
C) F
D) F
E) T