Medical Physiology Mid-Semester 2 CAT — 2021 (Past Paper)

Question 1

Complete Marked out of 1.00 Which ONE of the following causes indirect inhibition at the synapses? Select one:

Accepted Answer

If both flexors and extensors are inhibited.

Question 2

Complete Marked out of 1.00 The following statement is TRUE about the development of immune cells: Select one:

Accepted Answer

Mast cells mature in the thymus after leaving the bone marrow

Question 3

Complete Marked out of 1.00 Immune privileged sites include the following EXCEPT: Select one:

Accepted Answer

Gravid uterus

Question 4

Complete Marked out of 1.00 The following are some of the integrative functions of neuronal synapses EXCEPT Select one:

Accepted Answer

prevention of backward transmission of impulses

Question 5

Complete Marked out of 1.00 Which type of sensation is most affected in the lesions in sensory cortex? Select one:

Accepted Answer

Temperature differentiation

Question 6

Complete Marked out of 1.00 The Figure showing the weight of 21 subjects suggests: ![boxplot showing weight distribution of 21 subjects with outliers at around 45 and 143](https://cdn.ompathstudy.com/uploads/2026/08/y1-physio-midsem2-2021-p003-cf8ceb55.jpg) s Select one:

Accepted Answer

The lightest and heaviest subjects are within the normal distribution

Question 7

Complete Marked out of 1.00 Intrafusal fibres Select one:

Accepted Answer

house extrafusal fibres

Question 8

Complete Marked out of 1.00 Sensory receptors Select one:

Accepted Answer

. For smell (the olfactory receptors) are actual nerve cells

Question 9

Complete Marked out of 1.00 Figure 1 showing the weight of 21 subjects suggests: ![Box plot showing the weight distribution of 21 subjects](https://cdn.ompathstudy.com/uploads/2026/08/y1-physio-midsem2-2021-p004-0cf66344.jpg) Select one:

Accepted Answer

. The median weight is 100 kilograms

Question 10

Marked out of 1.00 In both excitable and nonexcitable cells, transmembrane signalling is a vital physiological role of: Select one:

Accepted Answer

K+ channels

Question 11

Marked out of 1.00 Which channel membrane protein is specifically important in the process of neurotransmitter release? Select one:

Accepted Answer

neurotransmitter receptor sodium channels.

Question 12

Marked out of 1.00 The Golgi tendon organ Select one:

Accepted Answer

mediates reflexes that protect muscle from overstretching

Question 13

Marked out of 1.00 Slowly adapting receptors include all the following types, except: - Select one:

Accepted Answer

free nerve endings

Question 14

Complete Marked out of 1.00 Damage to cutaneous receptors would limit the ability to detect all of the following except . Select one:

Accepted Answer

touch.

Question 15

Complete Marked out of 1.00 If I tell you that our very own Dr. Onyango has just discovered a new membrane channel that can change the membrane potential of neurons from -65 mV to -60 mV when activated, how would you characterize it? Select one:

Accepted Answer

as a new hyperpolarizing IPSP.

Question 16

Complete Marked out of 1.00 The resting potential of most cells is most dependent on the transmembrane concentration gradient of: Select one:

Accepted Answer

Calcium

Question 17

Complete Marked out of 1.00 Membrane excitability will be increased by the greatest amount by Select one:

Accepted Answer

Decreasing extracellular H+

Question 18

Complete Marked out of 1.00 The muscle spindle Select one:

Accepted Answer

gamma efferent fibers supply its non contractile ends

Question 19

Complete Marked out of 1.00 Concerning withdrawal reflexes Select one:

Accepted Answer

they are monosynaptic in nature

Question 20

Complete Marked out of 1.00 General sensations: - Select one:

Accepted Answer

originate from all sensory receptors of the body

Question 21

Complete Marked out of 1.00 Conduction of action potentials is faster in myelinated axons. This happens mainly because these axons Select one:

Accepted Answer

expend (use) less energy.

Question 22

Complete Marked out of 1.00 Receptor molecules on the surface of a cell Select one:

Accepted Answer

determine that cell's response and bind to all ligands.

Question 23

Complete Marked out of 1.00 Tetanus toxin and botulinum toxin exert their effects by disrupting the function of SNARES, inhibiting Select one:

Accepted Answer

The function of voltage-gated ion channels

Question 24

Complete Marked out of 1.00 In the interpretation of Figure 2 the following statement is TRUE: ![Histogram showing Density versus Age](https://cdn.ompathstudy.com/uploads/2026/08/y1-physio-midsem2-2021-p009-f67fc7c9.jpg) Select one:

Accepted Answer

The oldest subject influences the median more than the mean age

Question 25

Complete Marked out of 1.00 Inactivation of the sodium-potassium pump will cause Select one:

Accepted Answer

An increase in the excitability of nerve cells

Question 26

Complete Marked out of 1.00 51\. The output of a nerve cell goes through the Select one:

Accepted Answer

Axon

Question 27

Complete Marked out of 1.00 In the autonomic Nervous system all the following statements are correct Except: Select one:

Accepted Answer

b. In parasympathetic ganglia, the ratio of preganglionic fibres to Postganglionic fibers is 1:32.

Question 28

Complete Marked out of 1.00 27\. Myeloid cells in innate and adaptive immunity EXCLUDE the following: Select one:

Accepted Answer

Neutrophils

Question 29

Complete Marked out of 1.00 15\. Why do some normal cells fail to respond to a chemical signal? Select one:

Accepted Answer

Some cells are completely without ligands.

Question 30

Complete Marked out of 1.00 14\. Neurotransmitters and neurohormones both Select one:

Accepted Answer

are released by neurons and affect only cells with specific receptors.

Question 31

Complete Marked out of 1.00 Which of the following mechanisms allows the membrane potential to go back to its resting value when the membrane potential is at the peak of the action potential? Select one:

Accepted Answer

opening of neurotransmitter (ligand) -gated potassium channels.

Question 32

Marked out of 1.00 Depolarization occurs because Select one:

Accepted Answer

more Na+ diffuse into the cell than K+ diffuse out of it.

Question 33

Marked out of 1.00 The-----------------------------------plays a key role in terminating action potentials: Select one:

Accepted Answer

H+ channels

Question 34

Marked out of 1.00 Which is NOT a basic method of cell-to-cell communication? Select one:

Accepted Answer

nerve and blood-transported signals

Question 35

Marked out of 1.00 Detection of the stimulus modality depends upon: - Select one:

Accepted Answer

the anatomical connections between the receptors and specific sensory

Question 36

Complete Marked out of 1.00 The resting membrane potential in a nerve cell Select one:

Accepted Answer

Is stable in pace-maker cells

Question 37

Complete Marked out of 1.00 Which of the following statements regarding temperature receptors is FALSE? Select one:

Accepted Answer

There are more cold receptors in the skin than warm receptors.

Question 38

Complete Marked out of 1.00 As regards to transduction, the following is false Select one:

Accepted Answer

G-proteins are employed when signal amplification is needed

Question 39

Complete Marked out of 1.00 What is the main mechanism contributing to the absolute refractory period in neurons: Select one:

Accepted Answer

the voltage-dependent sodium channels cannot be opened.

Question 40

Complete Marked out of 1.00 A neurology resident was conducting research in an electrophysiology laboratory and was studying the functional anatomy of synaptic transmission. Which of the following physiologic processes is correctly paired with a structure? Select one:

Accepted Answer

Endplate potential: muscarinic cholinergic receptor

Question 41

Complete Marked out of 1.00 What would happen to the resting membrane potential of a neuron if sodium (Na+) channels were normally open in the membrane, but everything else was the same? Select one:

Accepted Answer

nothing much would happen, and it would remain at approximately -65 mV.

Question 42

Complete Marked out of 1.00 During inflammation Select one:

Accepted Answer

The second macrophage invasion is the first line of defense

Question 43

Complete Marked out of 1.00 The Hawaiian arrow poison palytoxin inhibits the Na+-K+ ATPase, locking it into such a position that it acts as a nonspecific ion channel. Which of the following is not true of the effects of palytoxin Select one:

Accepted Answer

Its symptoms are probably similar to those of ouabain.

Question 44

Complete Marked out of 1.00 During depolarization, which of the following statements about voltage-gated ion channels is TRUE? Select one:

Accepted Answer

K+ gates open before Na+ gates

Question 45

Complete Marked out of 1.00 Cells that respond to signals are usually called Select one:

Accepted Answer

junctions.

Question 46

Complete Marked out of 1.00 The following are some of the ways transmission at the synapse can be inhibited EXCEPT Select one:

Accepted Answer

causing an increase in ECF Mg++

Question 47

Complete Marked out of 1.00 The principle of divergence with regard to reflex physiology, is where Select one:

Accepted Answer

many efferents directly synapse on several end organs

Question 48

Complete Marked out of 1.00 The ability to localize the site of stimuli depends upon: - Select one:

Accepted Answer

the nature of the stimulus

Question 49

Complete Marked out of 1.00 Some have compared the "all or none" action potential to flushing a toilet. The absolute refractory period (when no amount of pressing the lever will produce another flush) is set by: Select one:

Accepted Answer

the inactivation of voltage gated sodium channels

Question 50

Complete Marked out of 1.00 The adequate stimuli for muscle spindle as a sensory receptor is Select one:

Accepted Answer

touch

Medical Physiology Mid-Semester 2 CAT — 2021 (Past Paper)

Questions, Answers & Explanations