Chapter 18

Question 1

Two systems that act together to coordinate all systems of the body

Answer 1

Nervous and endocrine

Question 2

Endocrine vs. exocrine glands

Answer 2

• Secrete hormones
• No ducts; secrete hormones directly into interstitial fluid surrounding them
• Include pituitary, thyroid, parathyroid, adrenal, and pineal glands

vs.

• Secrete their products into ducts
• None of the products are hormones
• Include sudoriferous (sweat), sebaceous (oil), mucous, and digestive glands

Question 3

How concentration of a hormone affects number of receptors on target cells

Answer 3

Hormones traveling throughout the body will only affect target cells that possess specific protein receptors for the hormones

Question 4

Two types of local hormones

Answer 4

• Paracrine: affect nearby cells such as the digestive hormones produced in the stomach (stimulate secretion of gastric juice in the stomach)
• Autocrine: affect the cells that produce them such as interleukins produced in the immune system

Question 5

Two types of hormones based on chemical solubility

Answer 5

• Lipid soluble: circulate bound to transfer proteins
• Water-soluble: circulate freely in plasma

Question 6

What target cells respond to hormones based on

Answer 6

• Hormone concentration
• Number of receptors
• Influence of other hormones

Question 7

3 main factors that control hormone secretion

Answer 7

1. Nervous system signals
2. Chemical changes in the blood
3. Other hormones

Question 8

Most hormone secretion is regulated by _______________.

Answer 8

Negative feedback

Question 9

Why negative feedback helps hormones maintain homeostasis

Answer 9

Secretion can turn on and off when needed

Question 10

Positive feedback vs. negative feedback

Answer 10

When a change in some variable causes a reaction which increases that change

vs.

When a change in some variable causes a reaction which decreases that change

Question 11

Components of feedback loop

Answer 11

• Stimulus
• Controlled condition
• Receptors
• Control center
• Effectors
• Response

Question 12

How hypophyseal portal system differs from usual circulation pathway

Answer 12

Flows from one capillary network into a portal vein, then into second capillary network before returning into the heart

Question 13

Releasing and inhibiting of hormones of the hypothalamus affect the function of the ___________.

Answer 13

Pituitary, this is an example of a synergistic hormone

Question 14

Hormones of anterior pituitary which affect hormones from other endocrine glands such as the thyroid, adrenal glands, and gonads

Answer 14

Trophic hormones (example of synergistic hormone)