Chapter 45.1

Question 1

Overview

Hormones

Answer 1

chemical signals that are secreted into the circulatory system and communicate regulatory messages within the body

Question 2

Two systems coordinate communication throughout the body:

Endocrine System

Answer 2

The endocrine system secretes hormones that coordinate slower but longer-acting responses including reproduction, development, energy metabolism, growth, and behavior

Slow & long-lasting

Question 3

Two systems coordinate communication throughout the body:

Nervous System

Answer 3

The nervous system conveys high-speed electrical signals along specialized cells called neurons; these signals regulate other cells

Fast & Short-lasting

Question 4

Local Regulators

Answer 4

Local regulators are molecules that act over short distances, reaching target cells solely by diffusion

Question 5

Paracrine Signaling

Answer 5

In paracrine signaling, the target cells lie near the secreting cells

Question 6

Autocrine Signaling

Answer 6

In autocrine signaling, the target cell is also the secreting cell

Question 7

Pheromones

Answer 7

• Members of the same animal species sometimes communicate with pheromones, chemicals that are released into the environment

Question 8

Endocrine Tissues and Organs

Endocrine Glands

Answer 8

• In some tissues, endocrine cells are grouped together in ductless organs called endocrine glands
• Endocrine glands secrete hormones directly into surrounding fluid

Question 9

Endocrine Tissues and Organs

Exocrine Glands

Answer 9

Have ducts and which secrete substances onto body surfaces or into cavities

opposite of endocrine glands

Question 10

Signal Transduction

Answer 10

The process by which a cell responds to substances outside the cell through signaling molecules found on the surface of and inside the cell.

Question 11

Epinephrine

Answer 11

• The hormone epinephrine has multiple effects in mediating the body’s response to short-term stress
• Epinephrine binds to receptors on the plasma membrane of liver cells
• This triggers the release of messenger molecules that activate enzymes and result in the release of glucose into the bloodstream

Question 12

Signaling by Local Regulators

Answer 12

• Local regulators are secreted molecules that link neighboring cells or directly regulate the secreting cell
• Types of local regulators:
  
  • Cytokines and growth factors
  • Nitric oxide (NO)
  • Prostaglandins

Question 13

Prostaglandins

Answer 13

• In the immune system, prostaglandins promote fever and inflammation and intensify the sensation of pain
• Prostaglandins help regulate aggregation of platelets, an early step in formation of blood clots