unit test / practice quizzes

Question 1

A given signal molecule…

Question options:

a)

Will elicit the same response regardless of the target cell type

b)

May elicit different responses in different target cells or after binding with different receptor types

c)

Will elicit the same response regardless of the receptor type

Answer 1

b)

May elicit different responses in different target cells or after binding with different receptor types

Question 2

What is a key difference between a local (paracrine) regulator and a hormone?

Question options:

a)

Local regulators diffuse to neighbouring cells; hormones usually travel throughout the body to distant target cells

b)

Local regulators initiate short-term responses; hormones trigger longer-lasting responses

c)

The signal transduction pathways of local regulators do not involve second messengers; pathways triggered by hormones do involve second messengers

d)

Local regulators often open ligand-gated channels and affect ion concentrations in cells; hormones bind with intracellular receptors and affect gene expression

e)

Local regulators are small, hydrophobic molecules; hormones are either large polypeptides or steroids

Answer 2

a)

Local regulators diffuse to neighbouring cells; hormones usually travel throughout the body to distant target cells

Question 3

What event is common to ALL signal transduction pathways?

Question options:

a)

Protons are transferred between molecules

b)

Calcium ions bind to/activate proteins

c)

Phosphates are transferred between molecules

d)

Cyclic nucleotides are formed

e)

Proteins change in conformation/activity

Answer 3

e)

Proteins change in conformation/activity

Question 4

A hormone traveling in the bloodstream…

Question options:

a)

Is drawn to cells bearing its receptors by chemical forces

b)

Travels only to cells with receptors for that hormone

c)

Travels to all cells but elicits responses only in cells with receptors for that hormone

Answer 4

c)

Travels to all cells but elicits responses only in cells with receptors for that hormone

Question 5

A signal molecule needs a second messenger if…

Question options:

a)

It travels to its target via the bloodstream

b)

It readily crosses the plasma membrane and binds to a receptor in the cytosol

c)

It cannot cross the plasma membrane

d)

Both (b) and (c) are true

Answer 5

c)

It cannot cross the plasma membrane

Question 6

Second messengers can be…

Question options:

a)

Modified nucleotides

b)

Produced from membrane phospholipids

c)

Ions

d)

All of the above

Answer 6

d)

All of the above

Question 7

A second messenger participates in a signal transduction pathway by…

Question options:

a)

Dampening the message once the signal molecule has left the receptor

b)

Relaying a signal from the outside to the inside of the plasma membrane

c)

Relaying a message by phosphorylating downstream proteins

d)

Relaying a message from the cytosolic side of the membrane throughout the cytosol

e)

Transporting a signal molecule through the hydrophobic plasma membrane

Answer 7

d)

Relaying a message from the cytosolic side of the membrane throughout the cytosol

Question 8

Glucagon, a protein hormone, acts via a G-protein coupled receptor (GPCR) that acts via increasing intracellular levels of cyclic AMP.

In the situation above, which components would be considered the first and second messengers, respectively?

Question options:

a)

Glucagon, cyclic AMP

b)

G-protein coupled receptor, adenylyl cyclase

c)

Glucagon, adenylyl cyclase

d)

G-protein, Gα subunit

e)

G-protein, cyclic AMP

Answer 8

a)

Glucagon, cyclic AMP

Question 9

Once it enters intestinal epithelial cells, cholera toxin will…

Question options:

a)

Act on a trimeric G protein to prevent dissociation of the α subunit from the βγ subunit

b)

Inhibit secretion of water into the intestinal lumen

c)

Inhibit adenylyl cyclase activity

d)

Block GTPase activity of the Gα subunit

e)

b and d

Answer 9

d)

Block GTPase activity of the Gα subunit

Question 10

Both norepinephrine (NE) and phenylephrine, a drug used as a decongestant, bind to alpha1 adrenergic receptors and elicit the same response. In this context, NE is _____ of phenylephrine.

Question options:

a)

An inhibitor

b)

An agonist and blocker

c)

An antagonist and competitor

d)

An antagonist

e)

An agonist

Answer 10

e)

An agonist

Question 11

During embryonic development, the neural tissue rolls up into a tube, forming a hollow neural tube that will form the _______.

Question options:

a)

brain

b)

peripheral nervous system

c)

central nervous system

d)

spinal cord

e)

autonomic nervous system

Answer 11

c)

central nervous system

Question 12

A blockage of the median aperture of the fourth ventricle would be expected to cause …

Question options:

a)

increased intracranial pressure

b)

enlargement of ventricles

c)

hydrocephalus

d)

Any/all of the above

Answer 12

d)

Any/all of the above

Question 13

The blood-brain barrier …

Question options:

a)

consists of cerebral capillaries that are more tightly sealed than other capillaries in the body

b)

is a major barrier to lipophilic substances that do not have carrier proteins / channels to take them across endothelial cells

c)

involves a relationship between glial cells called astrocytes and endothelial cells of cerebral capillaries

d)

a and c

e)

a, b and c

Answer 13

d)

a and c

Question 14

The ventral roots of spinal nerves contain …

Question options:

a)

cell bodies of autonomic effector neurons

b)

cell bodies of somatic motor neurons

c)

ascending sensory tracts

d)

cell bodies of somatosensory neurons

e)

descending motor neurons

Answer 14

e)

descending motor neurons

Question 15

Sympathetic preganglionic fibres originate in …

Question options:

a)

thoracic and lumbar segments of the spinal cord, white matter

b)

thoracic and lumbar segments of the spinal cord, lateral horn gray matter

c)

the brainstem

d)

cranial and sacral segments of the spinal cord, lateral horn gray matter

e)

Both b and d

Answer 15

b)

thoracic and lumbar segments of the spinal cord, lateral horn gray matter

Question 16

Which of the following is NOT a part of the brainstem?

Question options:

a)

Pons

b)

Spinal cord

c)

Midbrain

d)

Medulla

Answer 16

b)

Spinal cord

Question 17

The corticospinal tracts carry …

Question options:

a)

descending motor information in the white matter of the spinal cord

b)

ascending sensory information in the white matter of the spinal cord

c)

ascending motor information in the white matter of the spinal cord

d)

descending sensory information in the white matter of the spinal cord

Answer 17

a)

descending motor information in the white matter of the spinal cord

Question 18

Wilder Penfield is known for …

Question options:

a)

a neurosurgical procedure for the treatment of severe epilepsy.

b)

his contributions to the varsity basketball program at Princeton.

c)

creating maps of the sensory and motor cortices of the brain.

d)

a and c

e)

a, b and c

Answer 18

d)

a and c

Question 19

The cerebrum refers to …

Question options:

a)

the highly folded outermost layer of gray matter surrounding the brain

b)

a brain region best known for coordination of motor function.

c)

a large forebrain region that features a thin, highly folded layer of gray matter on the outside and several subcortical structures within

d)

a deep brain structure involved in integrating sensory information and memory

e)

the region in the brain that receives somatosensory information

Answer 19

c)

a large forebrain region that features a thin, highly folded layer of gray matter on the outside and several subcortical structures within

Question 20

You have decided to put your best foot forward, the right one. Put the following structures in the order that describes the direction that neural information travels for this voluntary movement.
1. Lateral corticospinal tract
2. Ventral horn gray matter
3. Medulla
4. Primary motor cortex
5. Midbrain
6. Ventral root
Question options:

a)

4, 2, 1, 5, 3, 6

b)

4, 3, 5, 1, 6, 2

c)

4, 5, 3, 1, 2, 6

d)

4, 5, 3, 2, 1, 6

e)

2, 1, 4, 3, 5, 6

Answer 20

c)

4, 5, 3, 1, 2, 6

Question 21

The first order or upper motor neuron carrying information that will direct voluntary movement of the right foot will travel in the spinal cord in the ________, crossing at the level of the ______.

Question options:

a)

lateral corticospinal tract, medulla

b)

anterior (ventromedial) corticospinal tract, spinal segment

c)

lateral corticospinal tract, spinal segment

d)

dorsal columns, medulla

e)

anterior (ventromedial) corticospinal tract, medulla

Answer 21

a)

lateral corticospinal tract, medulla

Question 22

You have stepped on a tack with your bare left foot. What type of receptors would detect the information related to pain you experience?

Question options:

a)

Meissner’s corpuscles

b)

Merkel receptors

c)

Free nerve endings

d)

Ruffini corpuscles

e)

Pacinian corpuscles

Answer 22

c)

Free nerve endings

Question 23

You are snow-blowing your land lady’s driveway in exchange for a rent reduction. The ________ are the cutaneous sensory receptors that are most strongly stimulated by the vibration.

Question options:

a)

Pacinian corpuscles

b)

Meissner’s corpuscles

c)

free nerve endings

d)

Merkel receptors

e)

muscle spindles

Answer 23

a)

Pacinian corpuscles

Question 24

The cutaneous sensory receptors that would be used for reading *Braille would have _____ receptive fields, and ascend to the brain via the ________.

*https://en.wikipedia.org/wiki/Braille

Question options:

a)

small, corticospinal tract

b)

large, dorsal columns

c)

large, spinothalamic tract

d)

small, dorsal columns

e)

small, spinothalamic tract

Answer 24

d)

small, dorsal columns

Question 25

Information detected by fine touch receptors in the right hand travel via the ___________ to the ______________.

Question options:

a)

dorsal columns, primary motor cortex

b)

corticospinal tract, somatosensory cortex

c)

dorsal columns, somatosensory cortex

d)

spinothalamic tract, temporal lobe

e)

dorsal columns, frontal lobe

Answer 25

c)

dorsal columns, somatosensory cortex

Question 26

You are at home cooking some pasta with tomato sauce when all of a sudden you spill some scalding sauce on your LEFT foot! Choose the option that best describes the pathway taken by the sensory information that will be interpreted as pain.

Dorsal root ->

1. Dorsal columns
2. Dorsal horn gray matter
3. Synapse in medulla
4. Left somatosensory cortex
5. Right somatosensory cortex
6. Left spinothalamic tract
7. Right spinothalamic tract
8. Synapse in thalamus
   Question options:

a)

2, 7, 8, 5

b)

2, 6, 3, 8, 5

c)

2, 6, 3, 8, 4

d)

2, 1, 3, 8, 5

e)

2, 7, 3, 8, 5

Answer 26

a)

2, 7, 8, 5

Question 27

Afferent fibres that transmit information about fine touch in your finger tips are likely to be…

Question options:

a)

faster than fibres conducting information about pain and temperature

b)

slower than fibres conducting information about pain and temperature

c)

slower than fibres conducting information about muscle length and tension

d)

faster than fibres conducting information about muscle length and tension

e)

both a and c are true

Answer 27

e)

both a and c are true

Question 28

Muscle length is monitored by…

Question options:

a)

extrafusal muscle fibres

b)

Golgi tendon organs

c)

tendons

d)

muscle spindles

Answer 28

d)

muscle spindles

Question 29

Which neuron would be strongly stimulated by an isometric contraction?

Question options:

a)

Gamma motor neuron

b)

1b afferent

c)

1a afferent

d)

Alpha motor neuron

Answer 29

b)

1b afferent

Question 30

Activation of gamma motor neurons…

Question options:

a)

Tightens the intrafusal muscle fibres

b)

Inhibits muscle contraction in certain reflexes

c)

Typically occurs when the associated alpha motor neurons are activated

d)

a and c

e)

a, b and c

Answer 30

d)

a and c

Question 31

Rank the following senses with respect to how quickly their information travels to the CNS (fastest to slowest).

Fast pain, Fine touch, Muscle length

Question options:

a)

Fine touch > muscle length > fast pain

b)

Muscle length > fine touch > fast pain

c)

Fast pain > fine touch > muscle length

d)

Fine touch > fast pain > muscle length

e)

Muscle length > fast pain > fine touch

Answer 31

b)

Muscle length > fine touch > fast pain

Question 32

The olfactory bulb is…

Question options:

a)

The first structure encountered by olfactory information entering the brain

b)

The sensory epithelium that lines the back of the nasal cavity

c)

The structure in which second order neurons that have received neural input form olfactory receptor neurons continue on to the olfactory cortex via the olfactory tract

d)

The region of the cerebral cortex in which olfactory information is processed

e)

Both a and c

Answer 32

e)

Both a and c

Question 33

Which of the following is/are TRUE about olfaction?

Question options:

a)

Olfaction is mediated by modified epithelial cells that synapse with primary afferent neurons

b)

Olfactory receptor neurons express one unique type of odorant receptor protein

c)

Olfactory information travels from the olfactory epithelium in the nasal cavity to a thalamic relay en route to the olfactory bulb

d)

Each odour binds to and activates one unique type of odorant receptor protein

e)

Both b and d are true

Answer 33

b)

Olfactory receptor neurons express one unique type of odorant receptor protein

Question 34

Sweet tastes are detected when …

Question options:

a)

Sugars enter taste receptor cells, depolarizing the cells and leading to release of release of ATP that acts on the primary afferent neuron

b)

Sugars bind to ion channel proteins expressed on the plasma membranes of taste receptor cells leading to Ca influx and release of ATP that acts on the primary afferent neuron

c)

Sugars bind to and bend mechano-sensitive membrane proteins on taste receptor hair cells, causing opening of mechanically-gated channels, Ca influx and release of ATP that acts on the primary afferent neuron

d)

Sugars bind to G protein-coupled receptors expressed on the membranes of taste receptor cells and initiate a signal transduction cascade leading to Ca influx and release of ATP that acts on the primary afferent neuron

Answer 34

d)

Sugars bind to G protein-coupled receptors expressed on the membranes of taste receptor cells and initiate a signal transduction cascade leading to Ca influx and release of ATP that acts on the primary afferent neuron

Question 35

The event most closely associated with the initiation of the pressure wave within the perilymph of the vestibular duct is…

Question options:

a)

Movement of the bony ossicles

b)

Movement of the basilar membrane

c)

Vibration of the tympanic membrane

d)

Vibration of the oval window

e)

Vibration of the round window

Answer 35

d)

Vibration of the oval window

Question 36

Which statement(s) is/are true about the stimulation of hair cells in the organ of Corti?

Question options:

a)

Vibration of the oval window causes a fluid pressure wave within the vestibular duct

b)

The fluid pressure wave pushes on the tectorial membrane, bending the hair cell cilia that are embedded in it

c)

Bending of stereocilia as a result of the fluid wave causes opening or closing of ion channels, a change in neurotransmitter release and a change in action potential frequency in the primary afferent neuron

d)

a and c

e)

a, b and c

Answer 36

e)

a, b and c

Question 37

Factors believed to contribute to the perceived pitch of a sound include…

Question options:

a)

The location of the activated hair cells on the basilar membrane

b)

The amplitude of action potentials travelling in primary afferent neurons in the auditory nerve

c)

The frequency of action potentials travelling in primary afferent neurons in the auditory nerve

d)

The direction of bend of hair cell stereocilia

e)

a and c

Answer 37

e)

a and c

Question 38

You are a passenger in a car driving down Columbia at a constant speed. Upon spotting a family of geese crossing the road, the driver hits the brakes. Hair cells in the ______ would be strongly stimulated by this event.

Question options:

a)

cochlear duct

b)

semicircular canals

c)

retina

d)

utricle

e)

both b and d

Answer 38

d)

utricle

Question 39

The mammalian retina is said to be ‘inverted’ because…

Question options:

a)

Photoreceptor cells are depolarized in the dark, and respond to light by releasing less neurotransmitter

b)

The image that forms on the retina is upside down or inverted

c)

Neural information flows through retinal neurons backwards, from axons to dendrites

d)

The photoreceptor cells are at the back of the retina, furthest from light entering the eye, with their light-sensing ends facing away from entering light

Answer 39

d)

The photoreceptor cells are at the back of the retina, furthest from light entering the eye, with their light-sensing ends facing away from entering light

Question 40

In the mammalian retina, action potentials are generated in…

Question options:

a)

rods and cones

b)

bipolar cells

c)

ganglion cells

d)

a and c

e)

a, b and c

Answer 40

c)

ganglion cells

Question 41

Which of the following is/are true about the fovea?

Question options:

a)

Sensitivity in low light conditions is achieved by having many photoreceptor cells at the fovea converge on a given ganglion cell

b)

It is densely populated with rods

c)

Receptive fields are very small

d)

a and c

e)

a, b and c

Answer 41

c)

Receptive fields are very small

Question 42

When a rod cell is being stimulated by light…

Question options:

a)

The chromophore retinal is in the all trans form

b)

Cyclic GMP levels are high

c)

Cyclic nucleotide-gated cation channels close

d)

a and c

e)

a, b and c

Answer 42

d)

a and c

Question 43

Would a person who is blind due to trauma to the occipital lobe have a normal pupillary light reflex?

Question options:

a)

No, no blind person could possibly have a reflex response to light

b)

Yes, but only if they are exposed to particularly bright light

c)

No, the pupil of the eye that is directly exposed to the light would constrict, but there would be no consensual response of the other eye

d)

Yes, their pupils would likely be ‘equal and reactive to light’

Answer 43

d)

Yes, their pupils would likely be ‘equal and reactive to light’

Question 44

The vasculature of the mammalian kidney is unusual in that…

Question options:

a)

Each nephron has glomerular and peritubular capillary beds connected by an efferent arteriole

b)

Each nephron has glomerular and peritubular capillary beds connected by a portal vein

c)

It has ducts that nephrons empty into, which drain into the renal pelvis

d)

There are bends in the distal tubules of each nephron looping back toward Bowman’s capsule

e)

It has two capillary beds between the afferent and efferent arteriole of each nephron

Answer 44

a)

Each nephron has glomerular and peritubular capillary beds connected by an efferent arteriole

Question 45

What happens to renal blood flow when the afferent arteriole constricts?

Question options:

a)

It increases

b)

It decreases

c)

It stays the same

Answer 45

b)

It decreases

Question 46

In response to an increase in systemic arterial pressure, you would predict…

Question options:

a)

dilation of afferent arterioles

b)

constriction of afferent arterioles

c)

increased GFR

d)

little or no change in GFR

e)

Both b and d

Answer 46

e)

Both b and d

Question 47

What part of the nephron tubule is part of the juxtaglomerular apparatus?

Question options:

a)

The collecting duct where it joins the ureter

b)

The renal pelvis

c)

The descending limb of the loop of Henle where it connects to the ascending limb

d)

The proximal tubule where it contacts the descending limb of the loop of Henle

e)

The ascending limb of the loop of Henle where it connects with the distal tubule

Answer 47

e)

The ascending limb of the loop of Henle where it connects with the distal tubule

Question 48

Which of the following monitors tubular salt concentrations and can release paracrine factors that affect afferent arteriole diameter?

Question options:

a)

Macula densa cells

b)

Proximal tubular epithelial cells

c)

Glomerular capillaries

d)

Granular cells

e)

Podocytes around glomerular capillaries

Answer 48

a)

Macula densa cells

Question 49

As fluid moves within the tubules through the regions of the nephron, the fluid _______ is most similar in composition to plasma.

Question options:

a)

entering the proximal tubule

b)

leaving the proximal tubule

c)

leaving the distal tubule

d)

leaving the ascending limb of the loop of Henle

e)

leaving the collecting duct

Answer 49

a)

entering the proximal tubule

Question 50

The ion that is commonly linked to indirect active transport during reabsorption in nephrons is _______.

Question options:

a)

Na+

b)

Ca2+

c)

Cl-

d)

K+

e)

HCO3-

Answer 50

a)

Na+

Question 51

Na+ moves across the apical membrane of epithelial cells of the proximal tubule via…

Question options:

a)

ENac channels

b)

symporters that couple amino acid and Na+ transport

c)

sodium-glucose cotransporters (SGLTs)

d)

a and c

e)

a, b and c

Answer 51

e)

a, b and c

Question 52

Glucose reabsorption across the epithelium of the proximal tubule is accomplished by…

Question options:

a)

transport across the apical membrane against its concentration gradient, coupled with Na+

b)

transport across the apical membrane down its concentration gradient, coupled with Na+

c)

facilitated diffusion across the basolateral membrane down its concentration gradient

d)

a and c

e)

b and c

Answer 52

d)

a and c

Question 53

Excretion of significant amounts of protein in the urine …

Question options:

a)

is most likely due to an issue with glomerular filtration

b)

is a normal mechanism for clearing the body of excess nitrogenous compounds

c)

is pathological

d)

a and c

Answer 53

d)

a and c

Question 54

A multi-subunit protein hormone with a molecular weight of 24 kDa could be …

Question options:

a)

freely filtered at the glomerulus.

b)

reabsorbed from the renal tubules and recycled back into the circulation to act on target cells again.

c)

reabsorbed in the proximal tubule, degraded to amino acids by renal epithelial cells and taken into the circulation.

d)

a and c

e)

a, b and c

Answer 54

d)

a and c

Question 55

Human chorionic gonadotropin (hCG) is a glycoprotein (~36 kDa). Reabsorption of glycoprotein hormones is somewhat inefficient. In a patient with high plasma concentrations of hCG, which of the following is/are true?

Question options:

a)

The kidney is not a major route of elimination of this hormone.

b)

The hormone would be present in this person’s urine.

c)

The hormone would not be filtered at the glomerulus.

d)

Amino acids derived from this hormone would be present in this person’s circulation.

e)

b and d

Answer 55

e)

b and d

Question 56

The plasma concentration at which glucose first appears in the urine is called the __________.

Question options:

a)

sweet spot

b)

saturation point

c)

renal threshold

d)

transport maximum

e)

tubuloglomerular capacity

Answer 56

c)

renal threshold

Question 57

The renal clearance of a substance X is the …

Question options:

a)

concentration of X in a sample of urine.

b)

amount of X cleared from the plasma per unit time.

c)

volume of plasma cleared of X per unit time.

d)

excretion rate of X.

Answer 57

c)

volume of plasma cleared of X per unit time.

Question 58

If the clearance rate of X is less than the amount filtered, then …

Question options:

a)

more X is being secreted than reabsorbed.

b)

X is being secreted by the nephron.

c)

X will be rapidly cleared from the blood.

d)

X is being reabsorbed by the nephron.

Answer 58

d)

X is being reabsorbed by the nephron.

Question 59

If the clearance rate of X is more than the amount filtered, then …

Question options:

a)

X is being secreted.

b)

X is being reabsorbed.

c)

X will be rapidly cleared from the blood.

d)

both a and c are true

Answer 59

d)

both a and c are true

Question 60

The renal threshold for glucose is 300 mg/100 ml plasma. Your cousin, a type I diabetic, is having trouble regulating her sugar levels. Her plasma glucose is 400 mg/dL. Which of the following would be true:

Question options:

a)

Glucose in her blood would be freely filtered at the glomerulus.

b)

All the glucose filtered into the renal tubules would be reabsorbed.

c)

She would be excreting glucose in her urine.

d)

a and c

e)

a, b and c

Answer 60

d)

a and c

Question 61

In a study on renal function in diabetics, creatinine clearance was 120 ml/min and plasma glucose was 320 mg/dL. The transport maximum for glucose is 340 mg/min.

What was this person’s glucose excretion rate?

Question options:

a)

220 mg/min

b)

240 mg/min

c)

44 mg/min

d)

44 ml/min

e)

9 mg/min

Answer 61

c)

44 mg/min

Question 62

The final osmolarity of the urine is established …

Question options:

a)

in the renal pelvis

b)

during storage in the bladder

c)

as it passes through the collecting duct

d)

as it passes through the loop of Henle

e)

as it passes through the proximal tubule

Answer 62

c)

as it passes through the collecting duct

Question 63

Vasopressin acts on the collecting duct of the nephron to …

Question options:

a)

increase activity of the Na+/K+ ATPase on the basolateral membrane

b)

increase expression of ENaC channels on the basolateral surface

c)

increase salt reabsorption via secondary active transport

d)

increase water permeability by increasing the number of AQP2 (aquaporin) proteins expressed on the luminal surface

e)

Both b and d

Answer 63

d)

increase water permeability by increasing the number of AQP2 (aquaporin) proteins expressed on the luminal surface

Question 64

Your house-mate Matt has a condition called diabetes insipidus. His disease is caused by a loss-of-function mutation in the vasopressin receptor. Which of the following would be true of Matt:

Question options:

a)

He tends to produce a very concentrated urine.

b)

His condition could be treated with his niece’s anti-bedwettting medication, desmopressin.

c)

He tends to produce copious quantities of very dilute urine.

d)

a and b

e)

b and c

Answer 64

c)

He tends to produce copious quantities of very dilute urine.

Question 65

In the presence of maximal concentrations of vasopressin …

Question options:

a)

most of the water filtered at the glomerulus is reabsorbed in the proximal tubule.

b)

urine output is high.

c)

most of the water filtered at the glomerulus is reabsorbed in the distal tubule and collecting duct.

d)

the collecting duct is completely impermeable to water.

e)

urine osmolarity is less than 100 mOsM.

Answer 65

a)

most of the water filtered at the glomerulus is reabsorbed in the proximal tubule.

(vasopressin only effects collecting duct but 70% of reabsorption will still happen in the proximal tubule so A is correct)

Question 66

The ascending limb of the loop of Henle is permeable to water …

Question options:

a)

in the presence of aldosterone.

b)

in the presence of vasopressin.

c)

always

d)

never

Answer 66

d)

never

Question 67

Which of the following is required for formation of the salt gradient in the renal medulla?

Question options:

a)

The ascending limb must transport ions from the interstitium to the tubule.

b)

The descending limb must transport ions from the interstitium to the tubule.

c)

The ascending limb must transport ions from the tubule to the interstitium.

d)

The descending limb must transport ions from the tubule to the interstitium.

Answer 67

c)

The ascending limb must transport ions from the tubule to the interstitium.

Question 68

Inhibition of the NKCC transporter on the apical membrane of epithelial cells lining the ascending loop of Henle would result in …

Question options:

a)

inhibition of Na+ and Cl- reabsorption.

b)

disruption of the salt gradient in the renal medulla.

c)

increased urine production.

d)

a and c

e)

a, b and c

Answer 68

e)

a, b and c

Question 69

In response to increased plasma osmolarity, central osmoreceptors would …

Question options:

a)

expand and increase firing rate.

b)

shrink and increase firing rate.

c)

expand and decrease firing rate.

d)

shrink and decrease firing rate.

Answer 69

b)

shrink and increase firing rate.

Question 70

Which of the following would be a stimulus for aldosterone secretion?

Question options:

a)

Hyperkalemia

b)

Decreased blood pressure

c)

Increased blood pressure

d)

a and b

e)

a and c

Answer 70

d)

a and b

Question 71

Which of the following would be a physiological response to a decrease in blood volume?

Question options:

a)

Increased pulse rate

b)

Vasoconstriction

c)

Increased thirst

d)

Conservation of water by the kidneys

e)

All of the above

Answer 71

e)

All of the above

Question 72

Primary responses to ingestion of a large amount of salt include …

Question options:

a)

increased vasopressin

b)

increased aldosterone

c)

thirst

d)

a and c

e)

a, b and c

Answer 72

d)

a and c

Question 73

Which of the following is TRUE regarding angiotensin II?

Question options:

a)

It stimulates thirst

b)

It increases vasopressin secretion

c)

It activates the cardiovascular control center in the medulla

d)

It is a potent vasoconstrictor

e)

All of the above

Answer 73

e)

All of the above

Question 74

Jasmine has just run her first marathon, in sweltering heat. In the interests of having a fast time, she declined all offers of water at the aid stations. In this self-inflicted state of severe dehydration, which of the following would be elevated?

Question options:

a)

Plasma concentrations of vasopressin

b)

Plasma concentrations of aldosterone

c)

Pulse rate

d)

a and c

e)

a, b and c

Answer 74

d)

a and c

Question 75

Under normal conditions, the major source of acid in our bodies is derived from …

Question options:

a)

the conversion of carbon dioxide from aerobic metabolism to bicarbonate and H+

b)

hydrochloric acid, from the combination of H+ and Cl- in plasma

c)

backwash of acid coming from the stomach

d)

the deamination of amino acids

e)

lactic acid from anaerobic metabolism

Answer 75

a)

the conversion of carbon dioxide from aerobic metabolism to bicarbonate and H+

Question 76

In general, renal compensation for acidosis involves …

Question options:

a)

secreting protons across the apical membrane into the tubular fluid.

b)

secreting protons across the basolateral membrane into the interstitium.

c)

reabsorbing bicarbonate.

d)

a and c

e)

b and c

Answer 76

d)

a and c

Question 77

In the proximal tubule, bicarbonate …

Question options:

a)

diffuses across the basolateral membrane as CO2 and is moved across the apical membrane by a transporter.

b)

is secreted into the filtrate.

c)

is pumped from the epithelial cell into the interstitium by ATPases.

d)

diffuses across the apical membrane as CO2 and is moved across the basolateral membrane by a transporter.

Answer 77

d)

diffuses across the apical membrane as CO2 and is moved across the basolateral membrane by a transporter.

Question 78

Renal compensations for alkalosis would include transport of …

Question options:

a)

H+ into the interstitium by proximal tubule epithelial cells.

b)

HCO3- into the tubular fluid by Type B intercalated cells in the distal nephron.

c)

H+ into the interstitium by Type B intercalated cells in the distal nephron.

d)

a and b

e)

b and c

Answer 78

e)

b and c

Question 79

Renal compensations for perturbations in acid-base balance can disrupt potassium homeostasis because …

Question options:

a)

a transporter in Type A intercalated cells in the distal nephron involved in compensation for acidosis reabsorbs a K+ for every H+ it secretes

b)

the hormone aldosterone is released in response to both hyperkalemia and high pH

c)

a transporter in Type B intercalated cells in the distal nephron involved in compensation for alkalosis secretes a K+ for every H+ it moves into the interstitium

d)

a and c

e)

a, b and c

Answer 79

d)

a and c

Question 80

Hyperventilation due to a panic attack could result in …

Question options:

a)

increased reabsorption of H+.

b)

respiratory acidosis.

c)

metabolic alkalosis.

d)

respiratory alkalosis.

e)

metabolic acidosis.

Answer 80

d)

respiratory alkalosis.

Question 81

Severe diarrhea could result in …

Question options:

a)

respiratory acidosis.

b)

metabolic alkalosis.

c)

decreased renin secretion.

d)

metabolic acidosis.

e)

decreased vasopressin secretion.

Answer 81

d)

metabolic acidosis.

Question 82

Acinar cells of the pancreas secrete proteins into a duct that empties into the lumen of the small intestine. These proteins would be considered …

Question options:

a)

hormones

b)

neurohormones

c)

neurotransmitters

d)

exocrine secretions

e)

paracrine factors

Answer 82

d)

exocrine secretions

Question 83

Oxytocin, a peptide, is released by neuron terminals in the posterior pituitary gland. It enters the bloodstream and acts on uterine smooth muscle. In this context, this substance could be referred to as a …

Question options:

a)

hormone

b)

neurotransmitter

c)

neurohormone

d)

a and c

e)

a, b and c

Answer 83

d)

a and c

Question 84

Assuming constant release from the testes, effects of endogenous testosterone would be increased by …

Question options:

a)

increased expression of androgen receptors by target cells

b)

administration of an androgen antagonist

c)

decreased excretion of androgens into urine and feces

d)

a and c

e)

a, b and c

Answer 84

d)

a and c

Question 85

Endocrine cells producing large amounts of a peptide hormone would be characterized by …

Question options:

a)

extensive rough endoplasmic reticulum

b)

vesicles containing their hormone product near the plasma membrane

c)

extensive smooth endoplasmic reticulum

d)

a and b

e)

b and c

Answer 85

d)

a and b

Question 86

The genomic mechanism of action for steroids would include …

Question options:

a)

opening of ion channels

b)

driving transcription of particular genes leading to synthesis of proteins

c)

activation of intracellular kinase cascades

d)

a and c

e)

any of the above, depending on the hormone.

Answer 86

b)

driving transcription of particular genes leading to synthesis of proteins

Question 87

In the endocrine reflex in which plasma K+ concentrations are regulated by aldosterone, what structure or cell type serves as the integrating centre?

Question options:

a)

The aldosterone-secreting cell

b)

A region in the hypothalamus

c)

A region in the brainstem

d)

The region in the cerebral cortex responsible for ion homeostasis

e)

The adrenal medulla

Answer 87

a)

The aldosterone-secreting cell

Question 88

Which of the following secretes neurohormones?

Question options:

a)

Posterior pituitary

b)

Adrenal medulla

c)

Hypothalamus

d)

a and c

e)

a, b and c

Answer 88

a)

Posterior pituitary

Question 89

The cells in the anterior pituitary gland that secrete TSH would be expected to express receptors for …

Question options:

a)

Thyroxin (aka thyroid hormone, T4)

b)

TSH

c)

TRH

d)

a and c

e)

a, b and c

Answer 89

d)

a and c

Question 90

Plasma concentrations of gonadotropins (LH, FSH) in a ‘neutered’ male cat (testes removed) would be expected to be ____ (relative to before the procedure).

Question options:

a)

higher

b)

lower

c)

unchanged

Answer 90

a)

higher

Question 91

Taking a cortisol agonist would be expected to _____ plasma levels of ACTH and _____ the size of the adrenal gland.

Question options:

a)

decrease. increase

b)

not change, decrease

c)

decrease, decrease

d)

increase, decrease

e)

increase, increase

Answer 91

c)

decrease, decrease

Question 92

Put the following in order, as viewed from the lumen of the small intestine:

____ epithelium
____ serosa
____ submucosa
____ muscularis externa (circular and longitudinal muscle layers)
____ lamina propria

Answer 92

__1__ epithelium
__5__ serosa
__3__ submucosa
__4__ muscularis externa (circular and longitudinal muscle layers)
__2__ lamina propria

Question 93

When comparing the microanatomy of the renal tubules versus the gut tubes, which tissue component in the intestine is most comparable to the ‘interstitium’ of the kidney?

Question options:

a)

a.muscularis externa (circular and longitudinal muscle layers)

b)

submucosa

c)

serosa

d)

lamina propria

e)

epithelium

Answer 93

d)

lamina propria

Question 94

The ‘alkaline tide’ that can be detected in plasma after ingestion of a meal is a result of …

Question options:

a)

export of bicarbonate (in exchange for chloride) on the basolateral membrane of acid-secreting parietal cells of the stomach.

b)

decreased filtration of bicarbonate in the kidney.

c)

increased reabsorption of bicarbonate in the proximal tubule of the kidney.

d)

secretion of bicarbonate into the small intestine.

e)

leakage of bicarbonate across the intestinal epithelium into the circulation via the paracellular pathway.

Answer 94

a)

export of bicarbonate (in exchange for chloride) on the basolateral membrane of acid-secreting parietal cells of the stomach.

Question 95

Which statement best describes mechanisms underlying the secretion of saline (sodium chloride plus water) that dilutes the mucus in intestine and salivary glands?

Question options:

a)

diffusion of Cl- into the lumen through CFTR channels, with Na+ and water following passively via the paracellular pathway.

b)

active transport of Cl- into the interstitium, with Na+ and water following passively via the paracellular pathway.

c)

active transport of Cl- into the lumen through CFTR channels, with Na+ and water following passively via the paracellular pathway.

d)

active transport of Cl- into the lumen, with Na+ and water following passively via the paracellular pathway.

e)

active transport of Na+ across the apical membrane via Na+/K+-ATPase, with Cl- and water following passively via the paracellular pathway.

Answer 95

a)

diffusion of Cl- into the lumen through CFTR channels, with Na+ and water following passively via the paracellular pathway.

Question 96

Assume a drug taken by injection is going to be metabolized in the liver and excreted in the feces. Its path to the liver, and out of the liver would be …

Question options:

a)

hepatic portal vein -> sinusoids -> central vein of liver lobule -> bile canaliculi -> bile ductules

b)

hepatic portal vein -> central vein of liver lobule -> bile canaliculi -> bile ductules -> common hepatic duct

c)

hepatic artery -> sinusoids -> bile canaliculi -> bile ductules -> common hepatic duct

d)

hepatic portal vein -> sinusoids -> bile canaliculi -> bile ductules -> common hepatic duct

e)

hepatic vein -> hepatic portal vein -> sinusoids -> bile ductules -> common hepatic duct

Answer 96

c)

hepatic artery -> sinusoids -> bile canaliculi -> bile ductules -> common hepatic duct

Question 97

To be absorbed in the small intestine, starch must be broken down to _______ and moved across the apical membrane of intestinal epithelium by _______.

Question options:

a)

monosaccharide units, diffusion

b)

di- and trisaccharide units, active transport

c)

di- and trisaccharide units, coupled transport

d)

di- and trisaccharide units, diffusion

e)

monosaccharide units, coupled transport

Answer 97

e)

monosaccharide units, coupled transport

Question 98

Which order best describes the major steps in protein digestion?

Question options:

a)

endopeptidase, exopeptidase, acid denaturation

b)

exopeptidase, endopeptidase, acid denaturation

c)

acid denaturation, endopeptidase, exopeptidase

d)

acid denaturation, exopeptidase, endopeptidase

Answer 98

c)

acid denaturation, endopeptidase, exopeptidase

Question 99

Protein digestion involves …

Question options:

a)

secretions of chief cells in the stomach.

b)

enzyme activity associated with the brush border in the small intestine.

c)

exocrine secretions of the pancreas.

d)

a and c

e)

a, b and c

Answer 99

e)

a, b and c

Question 100

Bile salts are …

Question options:

a)

amphipathic derivatives of cholesterol.

b)

components of chylomicrons.

c)

stored in, and released by the gall bladder.

d)

a and c

e)

a, b and c

Answer 100

d)

a and c

Question 101

Select the sequence that best describes the journey of a triglyceride as it is digested and absorbed.

Question options:

a)

fat droplet -> micelle -> enterocyte -> chylomicron -> interstitium -> capillary

b)

fat droplet -> micelle -> apical membrane transporter -> enterocyte -> chylomicron -> basolateral membrane transporter -> interstitium -> lacteal

c)

fat droplet -> micelle -> apical membrane transporter -> enterocyte -> chylomicron -> basolateral membrane transporter -> interstitium -> capillary

d)

fat droplet -> micelle -> enterocyte -> chylomicron -> interstitium -> lacteal

e)

fat droplet -> chylomicron -> enterocyte -> micelle -> interstitium -> lacteal

Answer 101

d)

fat droplet -> micelle -> enterocyte -> chylomicron -> interstitium -> lacteal

Question 102

With respect to regulation of GI function, ‘long reflexes’ refer to …

Question options:

a)

parasympathetic efferent information from the brainstem to the GI tract that stimulates gastrointestinal activity.

b)

neural signals that initiate migrating motor complexes that travel down the GI tract.

c)

the cephalic reflexes of digestion, such that the sight and smell of food stimulate GI activity.

d)

a and c

e)

a, b and c

Answer 102

d)

a and c

Question 103

The first hormone identified and named …

Question options:

a)

is produced by cells lining the duodenum in response to acid coming from the stomach.

b)

earned Ivan Pavlov a Nobel prize.

c)

stimulates bicarbonate release by the pancreas.

d)

a and c

e)

a, b and c

Answer 103

d)

a and c

Question 104

Gastric acid secretion is stimulated by …

Question options:

a)

histamine from ECL cells.

b)

sympathetic stimulation.

c)

gastrin from G cells.

d)

a and c

e)

a, b and c

Answer 104

d)

a and c

Question 105

Which products of the intestine inhibit gastric acid secretion?

Question options:

a)

CCK

b)

secretin

c)

GLP-1

d)

a and c

e)

a, b and c

Answer 105

e)

a, b and c

Question 106

Which of the following gut hormones stimulates gall bladder contraction and pancreatic enzyme secretion?

Question options:

a)

motilin

b)

CCK

c)

gastric inhibitory peptide (GIP)

d)

gastrin

e)

secretin

Answer 106

b)

CCK

Question 107

Insulin is released in response to …

Question options:

a)

GIP

b)

presence of fat in small intestine

c)

GLP-1

d)

a and c

e)

a, b and c

Answer 107

d)

a and c

Question 108

Regulation of stomach function via the gastric phase is different from the cephalic phase, in that …

Question options:

a)

the cephalic phase (but not the gastric phase) involves negative feedback regulation of acid production via somatostatin from D cells.

b)

the cephalic phase results in direct neural stimulation of secretion by G cells, ECL cells and parietal cells, whereas gastric phase mechanisms are based on neural stimulation of only G cells.

c)

the cephalic phase (but not the gastric phase) requires the presence of food in the stomach.

d)

the cephalic phase (but not the gastric phase) involves neural signalling.

e)

the cephalic phase (but not the gastric phase) involves stimulation of ECL and parietal cells by gastrin.

Answer 108

b)

the cephalic phase results in direct neural stimulation of secretion by G cells, ECL cells and parietal cells, whereas gastric phase mechanisms are based on neural stimulation of only G cells.

Question 109

Secretin enters the pancreas via _______ and HCO3- exits the pancreas via ________.

Question options:

a)

hepatic portal vein, veins

b)

veins, ducts

c)

its arterial blood supply, hepatic portal vein

d)

ducts, ducts

e)

its arterial blood supply, ducts

Answer 109

e)

its arterial blood supply, ducts

Question 110

Ketogenesis typically occurs in situations in which …

Question options:

a)

dietary carbohydrate intake is too high and excess sugars are converted to ketones.

b)

more acetyl CoA is formed than can be used in the tricarboxylic acid cycle.

c)

dietary fat intake is too high, and fatty acids are converted to keto-acids.

d)

rates of lipolysis are high.

e)

b and d

Answer 110

e)

b and d

Question 111

During the fasted / postabsorptive state, muscle can contribute to maintenance of blood glucose levels by …

Question options:

a)

breaking down proteins and exporting amino acids to be used by the liver as gluconeogenic substrates.

b)

breaking down glycogen and exporting free glucose.

c)

exporting pyruvate or lactate to be used by the liver as a gluconeogenic substrate.

d)

a and c

e)

a, b and c

Answer 111

d)

a and c

Question 112

Possible fates of fatty acids include being …

Question options:

a)

catabolized for energy via β oxidation.

b)

used by the brain for energy

c)

re-esterified to triglycerides and stored in adipose cells.

d)

a and c

e)

a, b and c

Answer 112

d)

a and c

Question 113

A human with the same condition as the ob/ob mouse …

Question options:

a)

would be obese.

b)

would have high circulating levels of leptin.

c)

would respond to treatment with exogenous leptin.

d)

a and c

e)

a, b and c

Answer 113

d)

a and c

Question 114

Leptin is a protein hormone produced in ___________ that acts in the ___________.

Question options:

a)

adipose cells; medulla

b)

adipose cells; adrenal gland

c)

liver; medulla

d)

the small intestine; liver

e)

adipose cells; hypothalamus

Answer 114

e)

adipose cells; hypothalamus

Question 115

CCK, a hormone from the small intestine …

Question options:

a)

slows gastric activity.

b)

increases secretion of enzymes from pancreatic acini.

c)

decreases appetite.

d)

a and c

e)

a, b and c

Answer 115

e)

a, b and c

Question 116

Glucose sensing and insulin release by pancreatic beta cells involves these membrane proteins:

Question options:

a)

KATP leak channels

b)

SGLT transporters

c)

NaV, voltage-gated Na+ channels

d)

a and c

e)

a, b and c

Answer 116

a)

KATP leak channels

Question 117

Insulin secreted in response to a meal results in …

Question options:

a)

increased fat synthesis.

b)

enhanced cellular utilization of amino acids.

c)

increased glucose transport into muscle and adipose.

d)

enhanced cellular utilization and storage of glucose.

e)

all of the above

Answer 117

e)

all of the above

Question 118

Primary targets for insulin action include all of the following EXCEPT …

Question options:

a)

skeletal muscle glucose uptake.

b)

renal glucose reabsorption.

c)

protein synthesis in target cells.

d)

hepatic glycogen synthesis.

e)

adipose lipogenesis.

Answer 118

b)

renal glucose reabsorption.

Question 119

Contrast the insulin response to an oral glucose challenge versus an intravenous injection of glucose (assuming they both achieve the same plasma glucose concentrations):

Question options:

a)

The oral route would cause a greater insulin release because pancreatic β cells would be stimulated by both gut peptides and glucose in the blood.

b)

Injection would cause a greater insulin release because pancreatic β cells only monitor glucose in plasma.

c)

The oral route would cause a greater insulin release because the GI tract is closer to the pancreas.

d)

Injection would cause a greater insulin release because glucose in the blood stimulates pancreatic β cells more directly.

Answer 119

a)

The oral route would cause a greater insulin release because pancreatic β cells would be stimulated by both gut peptides and glucose in the blood.

Question 120

Diabetics who require exogenous insulin usually inject it rather than taking it as a pill because …

Question options:

a)

the hormone is a protein and will therefore be broken down in the digestive system.

b)

injecting it protects it from being excreted by the kidney.

c)

injecting it helps it to cross the blood-brain barrier.

d)

they prefer injecting themselves over the hassle of taking pills.

e)

a rapid rise in plasma insulin is required, to drop blood glucose quickly.

Answer 120

a)

the hormone is a protein and will therefore be broken down in the digestive system.

Question 121

Which effect is unique to cortisol?

Question options:

a)

increased lipolysis

b)

increased proteolysis

c)

increased gluconeogenesis

d)

increased blood glucose

e)

suppression of immune function

Answer 121

e)

suppression of immune function

Question 122

A person with a mutation resulting in a 21α-hydroxylase deficiency would be expected to have _____ ACTH levels and _____ adrenals.

Question options:

a)

normal, small

b)

normal, enlarged

c)

high, small

d)

high, normal

e)

high, enlarged

Answer 122

e)

high, enlarged

Question 123

Which group of hormones are most similar in their effects on metabolism?

Question options:

a)

cortisol, growth hormone, thyroid hormone

b)

glucagon, cortisol, growth hormone

c)

glucagon, insulin, thyroid hormone

d)

growth hormone, insulin, thyroid hormone

e)

glucagon, cortisol, epinephine

Answer 123

e)

glucagon, cortisol, epinephine

Question 124

Graves’ disease is caused by auto-antibodies that act as TSH agonists, which are not affected by the usual feedback loops. What will happen to thyroid gland size in a patient with Graves’ disease?

Question options:

a)

There will be no change.

b)

It will increase.

c)

It will decrease.

Answer 124

b)

It will increase.

Question 125

Hypocalcemia is detected by cells in the …

Question options:

a)

parathyroid gland

b)

hypothalamus

c)

medulla oblongata

d)

marrow of weight-bearing bones

e)

kidney

Answer 125

a)

parathyroid gland

Question 126

The active form of vitamin D3 (calcitriol) is released from the …

Question options:

a)

skin

b)

liver

c)

sun

d)

kidney

e)

parathyroid gland

Answer 126

d)

kidney

Question 127

A male taking synthetic androgens in an attempt to increase his muscle mass would be expected to have _________ and ___________.

Question options:

a)

low circulating LH/FSH, decreased testicular size.

b)

low circulating LH/FSH, increased testicular size.

c)

low circulating LH/FSH, unaffected testicular size.

d)

high circulating LH/FSH, increased testicular size.

e)

high circulating LH/FSH, decreased testicular size.

Answer 127

a)

low circulating LH/FSH, decreased testicular size.

Question 128

______________ are target cells for LH in the male.

Question options:

a)

Sertoli cells

b)

GnRH-releasing neurons in the hypothalamus

c)

Leydig cells

d)

Granulosa cells

e)

Spermatogonia

Answer 128

c)

Leydig cells

Question 129

Luteinization …

Question options:

a)

refers to regression of the corpus luteum.

b)

occurs during the follicular phase.

c)

refers to the formation of the corpus luteum.

d)

a and b are correct

e)

b and c are correct

Answer 129

c)

refers to the formation of the corpus luteum.

Question 130

In the male, the mesonephric duct …

Question options:

a)

gives rise to components of the internal genitalia

b)

degenerates in response to the actions of Anti-Mullerian Hormone

c)

develops in response to the actions of Anti-Mullerian Hormone

d)

degenerates in response to the actions of testosterone

Answer 130

a)

gives rise to components of the internal genitalia

Question 131

Natural fertilization occurs in the …

Question options:

a)

ovarian follicle

b)

uterus

c)

Fallopian tube

d)

cervix

e)

vagina

Answer 131

c)

Fallopian tube

Question 132

The first two cell types to differentiate in the mammal are …

Question options:

a)

fibroblasts and epithelial cells

b)

Sertoli and Leydig cells

c)

inner cell mass and trophectodermal cells

d)

neurons and glial cells

e)

granulosa and thecal cells

Answer 132

c)

inner cell mass and trophectodermal cells