Question 1

As a result of training,the sympathetic nervous system's response to a fixed submaximal work rate

Accepted Answer

Training can increase the efficiency of the cardiovascular and respiratory systems, leading to a decreased sympathetic nervous system response at a fixed submaximal work rate. This means that the body is able to meet the demands of exercise with less sympathetic nervous system activation, resulting in decreased heart rate, blood pressure, and stress on the body.

Question 2

Muscle glycogen breakdown is under dual control by both

Accepted Answer

Muscle glycogen breakdown is primarily controlled by the hormone adrenaline, which is released in response to stress or exercise. Adrenaline activates an enzyme called glycogen phosphorylase, which breaks down glycogen into glucose for use as fuel. Additionally, this process is also under the control of calcium and calmodulin, as they play a key role in activating glycogen phosphorylase. Therefore, choice A is the correct answer.

Question 3

The mobilization of free fatty acids from adipose tissue and glucose from liver glycogen would be stimulated by

Accepted Answer

Insulin promotes storage of glucose in liver glycogen and inhibits the breakdown of fat in adipose tissue, whereas glucagon stimulates the breakdown of liver glycogen into glucose and breakdown of fat in adipose tissue. Therefore, a decrease in insulin and an increase in glucagon would stimulate the mobilization of free fatty acids from adipose tissue and glucose from liver glycogen.

Question 4

The decrease in plasma volume and the increase in the osmolality of the plasma during prolonged exercise results in _________________ in antidiuretic hormone.

Accepted Answer

The decrease in plasma volume and increase in osmolality of the plasma during prolonged exercise triggers the release of antidiuretic hormone (ADH) from the pituitary gland in order to preserve water by decreasing urine output. Therefore, the correct choice is (A) an increase in ADH.

Question 5

If the thyroid gland does not produce a sufficient amount of T₃ or T₄,the resting metabolic rate will

Accepted Answer

T₃ and T₄ are hormones produced by the thyroid gland that regulate metabolism. If they are not produced in sufficient amounts, the metabolic rate slows down, leading to symptoms such as weight gain, fatigue, and cold intolerance. Therefore, the correct answer is B.

Question 6

During exercise of about 40% VO₂ max,the concentration of plasma cortisol

Accepted Answer

During moderate exercise (around 40% VO2 max), the concentration of plasma cortisol is typically lower than at rest due to the body's adaptation to the stress of exercise.

Question 7

Which of the following hormones is secreted from adipose tissue?

Accepted Answer

Both leptin and adiponectin are hormones that are secreted from adipose tissue. Leptin plays a role in regulating appetite and energy balance, while adiponectin is involved in insulin sensitivity and metabolism.

Question 8

Steroid hormones exert their primary effect by

Accepted Answer

Steroid hormones can pass through the membrane of cells and bind to receptors in the cytoplasm or nucleus. Once bound, the hormone-receptor complex can then regulate gene expression by binding to specific DNA sequences and activating or inhibiting transcription. This is the primary way that steroid hormones exert their effects on cells and tissues.

Question 9

Which of the following hormones are secreted by the adrenal medulla?

Accepted Answer

The adrenal medulla secretes epinephrine (also known as adrenaline) and norepinephrine as part of the sympathetic nervous system response to stress. Aldosterone, cortisol, and angiotensin II are secreted by the adrenal cortex.

Question 10

Hormones are defined as

Accepted Answer

Hormones are chemical messengers that are released into the blood by endocrine glands and transported to target cells throughout the body to regulate various physiological processes.

Question 11

Which of the following hormones is believed to exert a "permissive" effect on the mobilization of glucose from the liver and FFA from adipose tissue?

Accepted Answer

T3 and T4 (thyroid hormones) are known to have a "permissive" effect, meaning they enhance the responsiveness of tissues to other hormones like epinephrine and glucagon, facilitating the mobilization of glucose and free fatty acids.

Question 12

Which of the following hormones may be related to changes in mood and pain perception during endurance exercise?

Accepted Answer

Endorphins are known for their analgesic (pain-relieving) effects and are released during prolonged endurance exercise. They can also contribute to the feeling of euphoria or "runner's high" often experienced after endurance exercise. These mood-enhancing effects of endorphins have also been linked to the treatment of depression and anxiety.

Question 13

A hormone that is released from the pancreas at a higher rate during exercise to mobilize liver glucose and adipose tissue fatty acids is

Accepted Answer

Glucagon is the hormone that is released from the pancreas at a higher rate during exercise to mobilize liver glucose and adipose tissue fatty acids. It works in opposition to insulin, which promotes the uptake and storage of glucose and fatty acids. Somatostatin is not involved in glucose or fatty acid mobilization. Insulin levels would decrease during exercise, not increase.

Question 14

Plasma concentrations of growth hormone are elevated following bouts of short-duration,high intensity exercise.The primary effect of an increase in plasma concentrations of growth hormone is to

Accepted Answer

Elevated plasma concentrations of growth hormone promote the increase of protein synthesis, which leads to an increase in muscle mass and strength. It also promotes the breakdown of adipose tissue, leading to a reduction in body fat. However, growth hormone does not directly promote long bone growth, and while it can increase the mobilization of FFA, it does not reduce tissue use of blood glucose.

Question 15

When adenylate cyclase is activated by a hormone,the concentration of cyclic AMP increases in the cell even though the hormone does not enter the cell.This is an example of the __________________ mechanism of hormone action.

Accepted Answer

When adenylate cyclase is activated, it produces cyclic AMP which acts as a second messenger inside the cell without the hormone entering the cell. Therefore, this is an example of the second messenger mechanism of hormone action. Options A and B also describe mechanisms of hormone action, but they are not relevant to this specific example. Therefore, D is incorrect as it includes all options.

Question 16

Given the importance of maintaining plasma glucose levels constant during exercise,insulin secretion would be expected to ______________ during exercise.

Accepted Answer

Insulin secretion would be expected to decrease during exercise because exercise increases glucose uptake by the muscles, reducing the amount of glucose in the blood. Insulin secretion helps to lower blood glucose levels, so less insulin secretion is needed during exercise to maintain a constant plasma glucose concentration.

Question 17

Which of the following hormones is secreted by the thyroid gland and plays a role in the regulation of plasma calcium levels?

Accepted Answer

Calcitonin is a hormone secreted by the thyroid gland that plays a role in regulating plasma calcium levels by decreasing the release of calcium from bone and increasing calcium excretion by the kidneys. Thyroxine and triiodothyronine are thyroid hormones that regulate metabolism, growth, and development. Parathyroid hormone is secreted by the parathyroid gland and plays a role in increasing plasma calcium levels.

Question 18

Which of the following hormones is part of the General Adaptive Syndrome and is called the "stress" hormone?

Accepted Answer

Cortisol is the hormone that is part of the General Adaptive Syndrome and is commonly referred to as the "stress" hormone. It is released in response to stress and helps the body cope with the physical demands of stress by increasing blood sugar levels and suppressing the immune system. Epinephrine is also released in response to stress, but it is not part of the General Adaptive Syndrome. Renin is a hormone involved in blood pressure regulation and insulin is involved in glucose regulation.

Question 19

The term describing the cessation of the menstrual cycle resulting from lower estrogen levels in some female athletes is

Accepted Answer

Amenorrhea refers to the absence or cessation of menstrual periods. This can occur in female athletes who engage in intensive training and have low levels of estrogen, resulting in disrupted hormonal balance and cessation of menstrual periods. Dysmenorrhea refers to painful periods, eumenorrhea refers to a normal menstrual cycle, and menarche refers to the onset of a girl's first menstrual period.

Question 20

While hormones circulate to all tissues,some affect only a few tissues.This is due to the

Accepted Answer

The type of receptor at the tissue determines whether or not the tissue will respond to a particular hormone. Some hormones have specific receptors that are only found in certain tissues, so those hormones will only affect those specific tissues. The plasma concentration and concentration of the hormone are important factors, but they do not solely determine which tissues will be affected. The training state of the subject is also not a determining factor in which tissues will be affected by a particular hormone.

Quiz 6: Cell Signaling and Hormonal Response to Exercise