Biology: The Dynamic Science

Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter 42

The Endocrine System - all with Video Answers

Educators

Chapter Questions

Problem 1

Amine hormones are usually:
a. hydrophilic when secreted by the thyroid gland.
b. based on tyrosine.
c. paracrine but not autocrine.
d. not transported by the blood.
e. repelled by the plasma membrane.

Caroline Jones

Caroline Jones

Numerade Educator

Problem 2

Prostaglandins would be best described as inducers of:
a. male and female characteristics.
b. cell division.
c. nerve transmission.
d. smooth muscle contractions.
e. cell differentiation.

Caroline Jones

Numerade Educator

Problem 3

When the concentration of thyroid hormone in the blood increases, it:
a. inhibits TSH secretion by the pituitary.
b. stimulates TRH secretion by the hypothalamus.
c. stimulates the pituitary to secrete TRH.
d. stimulates the pituitary to secrete TSH.
e. activates a positive feedback loop.

Bryan Valdivia

Numerade Educator

Problem 4

Which of the following statements about endocrine targeting and reception is correct?
a. The idea that one hormone affects one type of tissue is illustrated when epinephrine binds to smooth muscle cells in blood vessels, as well as to beta cells in heart muscle.
b. The idea that one hormone affects one type of tissue is illustrated when epinephrine cannot activate both the receptors on liver cells and the beta receptors of heart muscle.
c. The idea that a target cell can respond to more than one hormone is illustrated by a vertebrate liver cell responding to insulin and glucagon.
d. The idea that a minute concentration of hormone can cause widespread effects demonstrates the specificity of cells for certain hormones.
e. The idea that the response to a hormone is the same among different target cells is shown when different liver cells are activated by insulin.

Caroline Jones

Numerade Educator

Problem 5

The posterior pituitary secretes:
a. hormones that control the hypothalamus.
b. IGF, which simulates cell division and protein synthesis.
c. ADH, which increases water absorption in the kidneys.
d. oxytocin, which controls egg and sperm development.
e. prolactin, which stimulates milk synthesis.

Bryan Valdivia

Numerade Educator

Problem 6

Blood levels of calcium are regulated directly by:
a. insulin synthesized by the alpha cells of the pancreas.
b. PTH made by the pituitary.
c. vitamin $D$ activated in the liver.
d. prolactin synthesized by the anterior pituitary.
e. calcitonin secreted by specialized thyroid cells.

Bryan Valdivia

Numerade Educator

Problem 7

If the human body is stressed, glucocorticoids:
a. promote the breakdown of proteins in the muscles and bones.
b. increase the amount of sodium reabsorbed from urine in the kidneys.
c. decrease potassium secretion from the kidneys.
d. decrease glucose uptake by cells in the nervous system.
e. inhibit the synthesis of glucose from noncarbohydrate sources.

Caroline Jones

Numerade Educator

Problem 8

When blood glucose rises:
a. alpha cells increase glucagon secretion.
b. beta cells increase insulin secretion.
c. urination decreases in a person with type 1 diabetes who has not recently received an insulin injection.
d. glucagon stimulates the breakdown of amino acids into glycogen.
e. target cells decrease their insulin receptors.

Bryan Valdivia

Numerade Educator

Problem 9

In mammals:
a. the suprachiasmatic nucleus of the pineal gland controls both male and female reproductive systems.
b. estradiol is produced by the hypothalamus to control ovulation.
c. melatonin controls anabolic steroid production.
d. GnRH stimulates LH to control testosterone production.
e. progesterone increases the secretion of LH from the posterior pituitary.

Caroline Jones

Numerade Educator

Problem 10

Insect development is regulated by:
a. ecdysone, a peptide secreted by the brain.
b. juvenile hormone, a terpenoid secreted by the corpora allata near the brain.
c. molt-inhibiting hormone, a steroid secreted by the prothoracic glands.
d. prothoracicotropic hormone, a steroid secreted by the hypothalamus.
e. melatonin, a peptide secreted by the brain in the larval stage.

Caroline Jones

Numerade Educator

Problem 11

A physician sees a patient whose symptoms include sluggishness, depression, and intolerance to cold. What disorder do these symptoms suggest?

Josee Pacheco

Numerade Educator

Problem 12

A 20 -year-old woman with a malignant brain tumor has her pineal gland removed. What kinds of side effects might this loss have?

Josee Pacheco

Numerade Educator

Problem 13

In integrated pest management, a farmer uses a variety of tools to combat unwanted insects. These include applications of either hormones or hormone-inhibiting compounds to prevent insects from reproducing successfully. How might each of these hormone-based approaches disrupt reproduction?

Josee Pacheco

Numerade Educator

Problem 14

The Environmental Protection Agency (EPA) defines endocrine disruptors as chemical substances that can "interfere with the synthesis, secretion, transport, binding, action, or elimination of natural hormones in the body that are responsible for the maintenance of homeostasis (normal cell metabolism), reproduction, development, and/or behavior." The chemicals, sometimes called environmental estrogens, come from both natural and human-made sources. A simple hypothesis is that endocrine disruptors act by mimicking hormones in the body. Many endocrine disruptors affect sex hormone function and, therefore, reproduction.
Examples of endocrine disruptors are the synthetic chemicals DDT (a pesticide), dioxins, and natural chemicals such as phytoestrogens (estrogen-like molecules in plants), which are found in high levels in soybeans, carrots, oats, onions, beer, and coffee. Design an experiment to investigate whether a new synthetic chemical (pick your own interesting scenario) is an endocrine disruptor. (Hint: You probably want to work with a model organism.)

Josee Pacheco

Numerade Educator

Problem 15

Which endocrine system evolved earlier, endocrine glands or neurosecretory neurons? Support your conclusion with information obtained from online research.

Josee Pacheco

Numerade Educator