Critical Thinking Questions

31.
Although there are many different hormones in the human body, they can be divided into three classes based on their chemical structure. Explain these classes and give one factor that distinguishes each.
  1. The classes are peptide hormones, which are water insoluble, and amino acid-derived and lipid-derived hormones, which are water soluble.
  2. The classes are lipid-derived hormones, which are water insoluble, and amino acid-derived and peptide hormones, which are water soluble.
  3. The classes are lipid-derived hormones, which are water soluble, and amino acid-derived and peptide hormones, which are water insoluble.
  4. The classes are amino acid-derived hormones, which are water insoluble, and lipid-derived and peptide hormones, which are water soluble.
32.
Explain how hormones promote homeostasis in the body.
  1. Hormones increases cell activity by binding to the receptors present in the cell.
  2. Hormones facilitate communication between cells present at very distant locations in the body.
  3. Hormones facilitate communication between cells at any distance in the body.
  4. Hormones mediate changes by directly binding to the intracellular hormone receptors.
33.
A new hormone is discovered that binds to receptors on the target cell surface. Describe the chemical class of hormone that this hormone could belong to and explain how you could discern the exact class.
  1. It belongs to the class lipid-derived or peptide hormone as it is water insoluble and thus requires a cell surface receptor. The exact class can be determined on the basis of the hormone’s size.
  2. It belongs to the class amino acid derived hormones as it is lipid insoluble and thus requires a cell surface receptor. This can be discerned by determining the exact structure of the hormone.
  3. It belongs to the class lipid-derived or peptide hormone as it is water insoluble and thus requires a cell surface receptor. This can be discerned by determining the exact structure of the hormone.
  4. It belongs to the class amino acid derived or peptide hormone as it is lipid insoluble and thus requires a cell surface receptor. The exact class can be determined on the basis of the hormone’s size.
34.
Explain why hormones are able to travel through the body but only affect certain cells.
  1. Hormones only affect cells that have plasma membrane receptors.
  2. Hormones only affect cells that have corresponding hormone receptors.
  3. Hormones only affect cells that have intracellular receptors.
  4. Hormones only affect cells that are infected.
35.
Discuss the important functions of hormone receptors.
  1. Hormone receptors can induce cell-signaling pathways and mediate changes in target cells in the presence of hormones.
  2. Hormone receptors can mediate changes in target cells and act as transcription regulators in the presence of hormones.
  3. Hormone receptors can induce cell-signaling pathways and act as transcription regulators in the presence of hormones.
  4. Hormone receptors can mediate changes in target cells and can stimulate signaling pathways in the presence of hormones.
36.
Describe how cell surface receptors and intracellular receptors are similar and how they differ.
  1. Both are types of hormone receptors at target cells. Cell surface receptors facilitate indirect mediation, whereas intracellular receptors facilitate direct mediation.
  2. Both are types of hormone receptors at target cells. Cell surface receptors facilitate direct mediation, whereas intracellular receptors facilitate indirect mediation.
  3. Both reside in the cytoplasm or in the nucleus. Cell surface receptors facilitate indirect mediation, whereas intracellular receptors facilitate direct mediation.
  4. Both reside in the cytoplasm or in the nucleus. Cell surface receptors facilitate direct mediation, whereas intracellular receptors facilitate indirect mediation.
37.
Explain why drinking alcohol often results in dehydration.
  1. Drinking alcohol reduces antidiuretic hormone production, which is a hormone that helps retain water.
  2. Drinking alcohol increases antidiuretic hormone production, which is a hormone that helps with water loss.
  3. Drinking alcohol reduces thyroid stimulating hormone production, which is a hormone that helps retain water.
  4. Drinking alcohol increases thyroid stimulating hormone production, which is a hormone that helps with water loss.
38.

Describe how gonadotropin-releasing hormone production is controlled by a negative feedback loop.

  1. Gonadotropin-releasing hormone decreases production of follicle-stimulating hormone, which decreases hormone production in the gonads. An increase in gonad hormone production then gonadotropin-releasing hormone production.
  2. Gonadotropin-releasing hormone stimulates production of follicle-stimulating hormone, which regulates hormone production in the gonads. An increase in gonad hormone production then inhibits gonadotropin-releasing hormone production.
  3. Gonadotropin-releasing hormone decreases production of luteinizing hormone, which decreases hormone production in the gonads. An increase in gonad hormone production then inhibits gonadotropin-releasing hormone production.
  4. Gonadotropin-releasing hormone stimulates production of luteinizing hormone, which regulates hormone production in the gonads. An increase in gonad hormone production then inhibits gonadotropin-releasing hormone production.
39.
Explain where insulin is stored and under what circumstances it is released.
  1. It is stored in the pancreas and is released as glucose increases in the blood to enhance the rate of glucose uptake.
  2. It is stored in the liver and is released as glucose increases in the blood to enhance the rate of glucose uptake.
  3. It is stored in the pancreas and is released as glucose levels decrease in blood to decrease the rate of glucose uptake.
  4. It is stored in the liver and is released as glucose levels decrease in the blood to decrease the rate of glucose uptake.
40.
Ralph is always thirsty and recently learned that he synthesizes mutated antidiuretic hormone (ADH). Discuss why Ralph would be at higher risk for diabetes insipidus.
  1. ADH helps in the loss of water. Overproduction of ADH would cause improper functioning of kidneys.
  2. Underproduction of ADH inhibits the release of aldosterone that would cause improper functioning of kidneys.
  3. ADH helps retain water. Underproduction of ADH would cause improper functioning of kidneys.
  4. ADH helps in retaining electrolytes. Underproduction of ADH causes improper functioning of kidneys.
41.
Describe how stress promotes water retention, which can lead to weight gain.
  1. Stress decreases osmolality, which increases antidiuretic hormone secretion. Antidiuretic hormone helps retain water.
  2. Stress increases osmolality, which increases antidiuretic hormone secretion. Antidiuretic hormone helps retain water.
  3. Stress increases osmolality, which decreases antidiuretic hormone secretion. Antidiuretic hormone helps with water loss.
  4. Stress decreases osmolality, which decreases antidiuretic hormone secretion. Antidiuretic hormone helps with water loss.
42.

Identify which type of feedback mechanism primarily controls hormone production and release and explain why this occurs.

  1. Positive-feedback loop to help maintain the water concentration in the body.
  2. Negative-feedback loop to help maintain the water concentration in the body.
  3. Negative-feedback loop to help maintain proper bodily functions within a specific range.
  4. Positive-feedback loop to help maintain proper bodily functions within a specific range.
43.
Compare and contrast humoral and hormonal stimuli.
  1. Both humoral and hormonal stimuli release proteins. Humoral stimuli are hormones that stimulate other hormones, whereas hormonal stimuli are extracellular fluid-related stimuli.
  2. Both humoral and hormonal stimuli release proteins. Humoral stimuli are extracellular fluid-related stimuli, whereas hormonal stimuli are hormones that stimulate other hormones.
  3. Both humoral and hormonal stimuli release hormones. Humoral stimuli are extracellular fluid-related stimuli, whereas hormonal stimuli are hormones that stimulate other hormones.
  4. Both humoral and hormonal stimuli release hormones. Humoral stimuli are hormones that stimulate other hormones, whereas hormonal stimuli are extracellular fluid-related stimuli.
44.

Explain why it would be problematic if most hormones were regulated by a positive-feedback loop.

  1. Excessive production of actions would be stimulated by hormones such as growth and blood glucose levels.
  2. Production of actions would be reduced by hormones such as growth and blood glucose levels.
  3. Inhibition of GnRH production by increase in gonad hormone levels.
  4. Inhibition of release of insulin by decrease in blood glucose concentrations.
45.

Identify what aldosterone regulates and explain how it is stimulated.

  1. Aldosterone regulates the amount of water excreted by the kidneys and causes direct water reabsorption from the kidney tubules. It is stimulated by decreased water concentration in blood, or increased amounts of blood potassium.
  2. Aldosterone regulates sodium concentrations in urine, sweat, the pancreas, and saliva. It is stimulated by decreased blood sodium ion concentrations, blood volume, or blood pressure, or increased amounts of blood potassium.
  3. Aldosterone regulates calcium concentrations in urine, saliva and the pancreas. It is stimulated by decreased blood calcium ion concentrations, blood pressure, blood volume, or increased amounts of blood potassium.
  4. Aldosterone regulates blood glucose levels by stimulating the breakdown of glycogen to glucose. It is stimulated by decreased concentrations of glucose levels in blood, blood volume, or blood pressure.
46.
Discuss which aspect of the endocrine system often renders extremely thin females less fertile. Explain why this occurs.
  1. Adipose tissue releases leptin, which is needed to produce gonadotropin-releasing hormone and gonadotropin. Leptin cannot be released without sufficient body fat.
  2. Adipose tissue releases thymosins needed to produce gonadotropin-releasing hormone and gonadotropin. Thymosins cannot be produced without sufficient body fat.
  3. Adipose tissue releases leptin needed to produce gonadotropin-releasing hormone and gonadotropin. Leptins cannot be produced in the absence of body fat.
  4. Adipose tissue releases leptin needed to produce estrogens and progesterone. Leptin cannot be released without sufficient body fat.
47.

The adrenal medulla secretes two types of hormones. Identify what is secreted and describe their functions.

  1. They secrete cortisol and aldosterone, which increase heart rate, breathing rate, muscle contractions, blood pressure, and blood glucose as short-term stress responses.
  2. They secrete epinephrine and norepinephrine, which increase heart rate, breathing rate, muscle contractions, blood pressure, and blood glucose as long-term stress response.
  3. They secrete cortisol and aldosterone, which increase heart rate, breathing rate, muscle contractions, blood pressure, and blood glucose as long-term stress responses.
  4. They secrete epinephrine and norepinephrine, which increase heart rate, breathing rate, muscle contractions, blood pressure, and blood glucose as short-term stress responses.