Question 1

A neuropeptide that may signal satiety is

Accepted Answer

CCK (cholecystokinin) is a neuropeptide that is released in response to food in the small intestine. It promotes the release of digestive enzymes and bile and also signals satiety by acting on receptors in the brain. TSH (thyroid-stimulating hormone), NPY (neuropeptide Y), and ACTH (adrenocorticotropic hormone) are not known to directly signal satiety.

Question 2

Neuropeptide Y (NPY) and agouti-related protein (AgRP)

Accepted Answer

Neuropeptide Y (NPY) and agouti-related protein (AgRP) are known to stimulate feeding behavior. They are produced in the hypothalamus and act on circuits involved in hunger and satiety, leading to increased food intake.

Question 3

Levels of the hormone ghrelin

Accepted Answer

Ghrelin levels increase when the body needs energy (during fasting) and decrease after eating, signaling satiety and the cessation of eating. This hormone plays a significant role in appetite regulation and energy balance.

Question 4

Karen has recently completed a very successful diet program and is now concerned about maintaining her weight loss. One of the challenges she must face is the fact that

Accepted Answer

Leptin is a hormone produced by fat cells that helps control hunger and metabolism. When someone loses weight, their fat cells produce less leptin, which can lead to increased hunger and difficulty maintaining weight loss. This is why choice B is the correct answer, as it correctly identifies the challenge Karen must face. The other choices are incorrect: A is untrue, as some people are successful in maintaining weight loss; C is incorrect because higher levels of leptin would actually suppress hunger, rather than increasing it; and D is incorrect because dieting does not make a person resistant to leptin, although being obese can potentially lead to leptin resistance.

Question 5

Leptin is produced and secreted by

Accepted Answer

Leptin is primarily produced and secreted by fat cells.

Question 6

The lateral hypothalamus communicates with the cerebral cortex and provides the necessary link between the hypothalamus's recognition of hunger and higher-order motivated behaviors that lead to eating using a peptide called

Accepted Answer

MCH (Melanin-Concentrating Hormone) is a peptide that the lateral hypothalamus uses to communicate with the cerebral cortex, linking hunger recognition to motivated eating behaviors.

Question 7

Animals stop eating on their own and must be force-fed following lesions of the

Accepted Answer

The lateral hypothalamus is known as the hunger center of the brain. Lesions in this area can lead to aphagia (lack of eating) because it disrupts normal hunger signals, leading animals to stop eating voluntarily.

Question 8

Low levels of leptin lead to

Accepted Answer

Leptin is a hormone that signals satiety to the brain and regulates energy balance. Low levels of leptin lead to an increase in feeding behavior, which is consistent with stimulation of the parasympathetic nervous system and suppression of thyroid-stimulating hormone (TSH) and adrenocorticotropic hormone (ACTH), as these hormones are involved in energy homeostasis. Therefore, option B is the correct choice.

Question 9

Neurons in the lateral hypothalamus involved with the initiation of complex feeding behaviors may secrete

Accepted Answer

Neurons in the lateral hypothalamus that are involved in initiating complex feeding behaviors secrete melanin-concentrating hormone (MCH) and orexins (hypocretins). These peptides stimulate feeding behavior and regulate energy balance. TSH and ACTH are hormones secreted by the pituitary gland that are involved in the regulation of metabolism and stress response, respectively, but they are not secreted by neurons in the lateral hypothalamus.

Question 10

In untreated Type I diabetes mellitus,

Accepted Answer

In untreated Type I diabetes mellitus, there is a lack of insulin production and therefore, glucose can not be moved from the blood into cells, resulting in abnormally high blood sugar levels. Excess glucose is not stored by cells, and blood sugar levels are not abnormally low. The blood may become hypertonic due to the high concentration of glucose.

Question 11

Cynthia has been diagnosed with a tumor in the vicinity of her lateral hypothalamus. Which of the following symptoms has Cynthia most likely experienced as a result of her condition?

Accepted Answer

The lateral hypothalamus is involved in regulating hunger and feeding behavior. Damage or dysfunction in this area can lead to a lack of appetite and subsequent weight loss.

Question 12

Cells releasing orexins (hypocretins) become more active when

Accepted Answer

Orexins (hypocretins) are neuropeptides that regulate wakefulness, appetite, and reward. The release of orexins is stimulated by low levels of leptin (a hormone that signals satiety) and high levels of ghrelin (a hormone that signals hunger), making choice C the best option. High levels of leptin and low levels of ghrelin, as seen in option D, would promote satiety and reduce the release of orexins, while options A and B are contradictory and would not stimulate the release of orexins.

Question 13

Dr. Sanders was excited to observe the effects of leptin on her obese laboratory mice and began to explore ways that leptin could be used to help people lose weight. It is likely that Dr. Sanders will

Accepted Answer

While leptin has been shown to be effective in reducing weight in mice, many obese humans are already producing high levels of leptin, and adding more would not necessarily result in weight loss. Additionally, some obese humans have developed a resistance to leptin, making it less effective even if administered in high doses. Therefore, it is unlikely that leptin would be as effective in humans as it is in mice.

Question 14

Glucoreceptors have been found in the

Accepted Answer

Glucoreceptors, which are involved in detecting glucose levels, have been identified in the hindbrain, particularly in areas like the hypothalamus and brainstem, which are crucial for energy homeostasis and glucose regulation.

Question 15

Research by Cannon and Washburn, in which Washburn swallowed a balloon, investigated the role of

Accepted Answer

Cannon and Washburn's research investigated the role of stomach contractions as cues for hunger. By measuring the movements of the balloon in Washburn's stomach, they were able to show that stomach contractions were correlated with feelings of hunger.

Question 16

(see Figure 9.18a) The structure indicated by #1 in this illustration is the

Accepted Answer

The structure indicated by #1 in Figure 9.18a is the paraventricular nucleus (PVN), which is located in the hypothalamus and is involved in regulating various physiological processes, including hunger and thirst. The other options, arcuate nucleus, VMH, and lateral hypothalamus, are also hypothalamic nuclei, but they are not the structure indicated by #1 in the given illustration.

Question 17

Which of the following brain regions is NOT associated with the liking aspect of reward?

Accepted Answer

The ventral tegmentum of the midbrain is primarily associated with the motivational and reinforcement aspects of reward, rather than the liking aspect. The other regions listed (ventral pallidum, nucleus accumbens, and orbitofrontal cortex) are all involved in processing the pleasurable or reinforcing aspects of rewards.

Question 18

Which of the following brain regions is NOT associated with the wanting aspect of reward?

Accepted Answer

The answer of  Which of the following brain regions is...

Question 19

Kendall has just eaten breakfast. Right after her meal,

Accepted Answer

After eating, the body's glucose levels rise due to the digestion and absorption of carbohydrates. In response, the pancreas releases insulin to help cells absorb glucose for energy, leading to high levels of both insulin and glucose in the blood.

Question 20

Symptoms of untreated diabetes mellitus include

Accepted Answer

Untreated diabetes mellitus can lead to high blood sugar levels, causing frequent urination which leads to dehydration and thirst. Additionally, the body may start breaking down fat and muscle for energy, resulting in unexpected weight loss.

Quiz 9: Homeostasis, Motivation, and Reward