Animal Physiology MCQ

Which of the following is a correct statement addressing the mechanism branch of physiology?

When certain cells in the duodenum detect high levels of undigested protein, the hormone CCK is released which triggers the pancreas to secrete enzymes into the lumen

The plasma membrane of all animal cells is composed of phospholipids arranged into a bilayer. Which of the following statements about the phospholipid bilayer is true?

Only hydrophobic substances are able to cross directly through the plasma membrane, without the help of channels and transporters

The pancreas is responsible for producing a large amount of secreted proteins: hormones that are secreted into the blood and enzymes that get released into the lumen of the gastrointestinal tract. Based on this information, in a pancreatic cell that was actively producing these proteins, which organelle would you expect to see present in relatively high amounts (compared to a cell that does not produce a lot of secretory proteins)?

Rough endoplasmic reticulum

Under which of the following scenarios would you expect the greatest rate of sodium diffusion across the plasma membrane?

Many open sodium channels, large concentration gradient, thin membrane

While working in a veterinary clinic, the vet asks you to grab a bag of sterile solution so that he can administer it intravenously into a dehydrated dog. When you get to the supply cupboard, you see three different types of sterile infusion solutions: water, 0.9% sodium chloride and 2% sodium chloride. Which bag of solution would you select to bring to the veterinarian and why?

0.9% sodium chloride- because it is isotonic compared to the animal's blood

Which of the following is an example of acute enzyme regulation?

After an animal has consumed a meal, there is an increase in the phosphorylation of some of the enzymes involved in glycolysis, which makes these enzymes more active

Regardless of whether a species is a ruminant or a non-ruminant, accessory organs play a critical role in the digestive processes. Which of the following statements about accessory organs is false?

Digesta only passes through the accessory organs if there is inadequate space in the lumen of the gastrointestinal tract

Which of the following does not stimulate salivation in the mouth of a pig?

Stomach distension

Unlike most non-ruminant species, horses have a large non-glandular region in their stomach. Which of the following statements correctly states a consequence related to this large non-glandular region?

Horses are more prone to developing gastric ulcers in the non-glandular region

Which hormone works to increase acid secretion in the stomach of non-ruminants?

Gastrin

In birds, which three organ collectively perform similar digestive functions to the stomachs of non-ruminant mammals?

Crop, Proventriculus, Gizzard

Pancreatitis is an inflammation of the pancreas and certain dogs may be especially pre-disposed to developing this condition. During pancreatitis, the release of the digestive enzymes into the gastrointestinal tract may be disrupted. In a dog suffering from a bout of pancreatitis, the digestion of which nutrients would you expect to be adversely affected?

Protein, Fat and Starch

Which of the following digestive processes does not occur in the small intestine?

Anti-peristalsis helps to keep digesta in the small intestine for as long as possible

How is bile secretion regulated in species with a gallbladder?

Endocrine system only

In what organ does the majority of dietary protein digestion occur in ruminants?

Rumen

Why are primary contractions an important part of the digestive process in ruminants?

They mix the more and less digested particles together which ensures more rapid digestion

When measuring the basal metabolic rate of two different animals, which of the following is not a condition that must be met?

Both animals must be the same size

Placing an ice pack on a hot animal will help to cool the animal via what method of heat exchange?

Conduction

When transporting solutes across the plasma membrane, _______________ do not bind to their solute, whereas ______________ do bind to their solute.

1. channels
2. transporters

___________ is a necessary component of fat digestion because it allows dietary fat to interact with its digestive enzymes.

Bile

___________ is the only energy substrate that can be metabolized both aerobically and anaerobically.

Glucose

When comparing a cow to a cat, the __________ has a higher whole-body basal metabolic rate and the _________ has a higher weight specific basal metabolic rate.

1. cow
2. cat

(T/F) All receptors produce secondary messengers when their "signal" binds.

F

(T/F) Homeostasis refers to an animal's ability to change its internal environment in response to changes in its external environment.

F

(T/F) Horses and other hindgut fermenters are able to absorb amino acids that originate from microbial protein.

F

(T/F) Aerobic ATP production is generally faster and yields greater amounts of ATP than anaerobic ATP production.

F

(T/F) Animals are able to both gain and lose heat through evaporation.

F

When peptide hormones bind to their receptors, which of the following statements correctly describes the typical mode of action of these hormones?

An increase in the production of secondary messengers, leading to the activation/deactivation of enzymes (or proteins) that are already present

Which division of the nervous system includes the somatic and autonomic nervous systems?

Peripheral nervous system

What part of the brain is required for sensation and voluntary movement?

Cerebral cortex

This region of the neuron is responsible for neurotransmitter release into the synapse.

Axon terminal

This membrane protein is essential for the establishment and maintenance of resting membrane potential.

Na+/K+-ATPase

Which of the following statements about action potentials is true?

Action potentials can only travel down the axon in one direction, which is towards the axon terminal

Which of the following would not be considered to be a part of the synapse between two neurons?

Axon of the pre-synaptic neuron

I pre-synaptic neuron #1 releases neurotransmitter that upon binding causes the post-synaptic neuron to depolarize by 5 mV at the same time as pre-synaptic neuron #2 releases neurotransmitter that causes the post-synaptic neuron to hyperpolarize by 6 mV, what type of summation is this and what will occur in the post-synaptic neuron?

Spatial summation; the post-synaptic neuron will not reach threshold for an action potential

In this type of synapse, there is a direct effect on the membrane potential of the post-synaptic cell, resulting in the hyperpolarization of the post-synaptic cell.

Type 2 ionotropic synapse

Which of the following correctly describes a difference between the somatic and autonomic branches of the peripheral nervous system?

The somatic nervous system uses acetylcholine as the neurotransmitter at the target tissue, whereas the autonomic nervous system may use either norephinephrine or acetylcholine

What is the name for the tissue layer that surrounds each individual muscle fiber?

Endomysium

Which of the following correctly lists the proteins that form the thin filament?

Actin, Troponin, Tropomyosin

In order for muscle contraction to occur, ATP binds to which of the myofilament proteins?

Myosin

Which of the following statements correctly describes what happens to the sarcomere during muscle contraction?

There is an increase in overlap of the thick and the thin filaments, resulting in a shortening of each sarcomere

This muscle fiber type is a fast twitch muscle, has an intermediate number of mitochondria and can make its ATP through both aerobic and glycolytic (anaerobic) means.

Type IIA

An action potential is able to spread along the axon of the neuron because as sodium ions enter the neuron through open Na+ channels, they depolarize adjacent segments of the axon, allowing voltage _________________ to be met and an action potential to be generated in this "new" segment of the axon.

threshold

Once an action potential reaches the axon terminal, the axon terminal membrane depolarizes to a certain threshold, resulting in the opening of voltage-gated _____________ channels, which is necessary for the release of neurotransmitter.

calcium

In an ionotropic synapse, the neurotransmitter receptor is a __________ _________ ___________, whereas in a metabotropic synapse, the neurotransmitter receptor is a _________________________________.

1. ligand-gated channel
2. G-protein coupled receptor

In the skeletal muscle, both the _____________ and _______________________________ contain voltage-gated calcium channels, which must dissociate from each other in order for muscle contraction to occur.

1. T-tubules
2. Sarcoplasmic reticulum

(T/F) Peptide neurotransmitters are made in the cell body of the neuron, whereas small molecule neurotransmitters may be made in the axon terminal of the neuron.

T

(T/F) Metabotropic synapses always result in a change in post-synaptic membrane potential, although whether or not it is an EPSP or an IPSP will depend on the specific neurotransmitter and receptor.

F

(T/F) Both the somatic and autonomic nervous systems require 2 neurons to go from the central nervous system to the target tissue for the motor response.

F

(T/F) The sarcolemma is the name for the specialized plasma membrane that surrounds skeletal muscle cells.

T

(T/F) An extensor muscle is typically located on the outside of the joint and when it contracts, the joint angle decreases.

F

Ionotropic only

1. Hearing
2. Touch

Metabotropic only

1. Smell
2. Vision

Depends- ionotropic in some cases, metabotropic in other cases

1. Only Taste