Question 1

Which of the following best describes the difference between the nervous and endocrine systems in terms of their effects on target cells?

Accepted Answer

The nervous system directly affects target cells using neurotransmitters, while the endocrine system indirectly affects target cells using hormones.

Question 2

A patient is given a hydrophilic hormone intravenously. Which of the following is most likely true about its transport and removal?

Accepted Answer

It travels freely in the blood and is removed quickly by the kidneys.

Question 3

Which type of chemical signal is secreted by cells into the extracellular fluid to affect nearby but different types of cells?

Accepted Answer

Paracrine signal

Question 4

Which of the following best explains why hydrophobic hormones can cross the phospholipid bilayer?

Accepted Answer

They are lipid-soluble and can diffuse through the hydrophobic core of the membrane.

Question 5

A hormone binds to a receptor on the cell surface and activates a G protein, which then stimulates adenylyl cyclase to produce cAMP. What type of hormone is most likely involved?

Accepted Answer

Hydrophilic amino acid-based hormone

Question 6

Which of the following is an example of a humoral stimulus for hormone secretion?

Accepted Answer

A change in blood glucose concentration triggers insulin secretion.

Question 7

What is the primary reason hydrophilic hormones require second messenger systems to exert their effects?

Accepted Answer

They are unable to cross the phospholipid bilayer and must use membrane-bound receptors.

Question 8

Which of the following best describes the process of up-regulation in hormone receptors?

Accepted Answer

Low levels of hormone stimulate an increase in the number of receptors on target cells.

Question 9

A patient has a tumor that secretes excess parathyroid hormone (PTH), leading to high blood calcium. Which feedback mechanism is most likely disrupted?

Accepted Answer

Negative feedback loop

Question 10

Which of the following is true regarding steroid hormones?

Accepted Answer

They are derived from cholesterol and are hydrophobic.

Question 11

Which of the following scenarios best illustrates a synergistic hormone interaction?

Accepted Answer

Growth hormone and thyroid hormone together produce a greater effect on metabolism than either alone.

Question 12

Which equation best represents the signal amplification that occurs in a second messenger system?

Accepted Answer

$$N_{hormone} \ll N_{second\ messenger}$$

Question 13

Which of the following is NOT a primary endocrine organ?

Accepted Answer

Kidney

Question 14

A hydrophobic hormone enters a target cell and binds to a receptor in the nucleus. What is the most likely result?

Accepted Answer

Alteration of gene transcription

Question 15

Which of the following best describes autocrine signaling?

Accepted Answer

A cell secretes a chemical that affects itself or cells of the same type.

Question 16

Which of the following is a correct statement about hormone removal from the body?

Accepted Answer

Hydrophilic hormones are removed faster than hydrophobic hormones.

Question 17

Which of the following is most likely to occur if a target cell is exposed to high concentrations of a hormone for a prolonged period?

Accepted Answer

Down-regulation of receptors

Question 18

Which of the following is a secondary endocrine organ?

Accepted Answer

Kidney

Question 19

Which of the following is a direct effect of hormone action on a target cell?

Accepted Answer

Activation of enzymes

Question 20

Which of the following best describes the role of negative feedback in endocrine regulation?

Accepted Answer

It reverses the initial stimulus to maintain homeostasis.

Lec 16: Endocrine System

Guida di studio - Domande di pratica

Study guide - Flashcard