Essentials of Human Anatomy & Physiology

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Slides 9.1 – 9.22

Seventh EditionElaine N. Marieb

Chapter 9The Endocrine System

Lecture Slides in PowerPoint by Jerry L. Cook

I. The Endocrine SystemI. The Endocrine System

Slide 9.1Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

A. Uses chemical messages (hormones) that are released into the blood

B. Hormones are produced by specialized cells

C. Cells secrete hormones into extracellular fluids

D. Blood transfers hormones to target sites

E. These hormones regulate the activity of other cells

• Reproduction

• Growth and development

• Mobilization of body defenses

• Maintenance of much of homeostasis

• Regulation of metabolism

II. The Chemistry of HormonesII. The Chemistry of Hormones

Slide 9.3Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

A. Amino acid-based hormones

Proteins

Peptides

Amines

B. Steroids – made from cholesterol

C. Prostaglandins – made from highly active lipids

III. Mechanisms of Hormone ActionIII. Mechanisms of Hormone Action

Slide 9.4Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

A. Hormones affect only certain tissues or organs (target cells or organs)

B. Target cells must have specific protein receptors

C. Hormone binding influences the working of the cells

D. Effects Caused by HormonesD. Effects Caused by Hormones

Slide 9.5Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

1. Changes in plasma membrane permeability or electrical state

2. Synthesis of proteins, such as enzymes

3. Activation or inactivation of enzymes

4. Stimulation of mitosis

E. Steroid Hormone ActionE. Steroid Hormone Action

Slide 9.6Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

1. Steroid hormones can diffuse through the plasma membrane of target cells

2. Enter the nucleus

3. Bind to specific sites on the cell’s DNA

4. Activate genes that result in synthesis of new proteins

Steroid Hormone ActionSteroid Hormone Action

Slide 9.7Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Figure 9.1a

F. Non-steroid Hormone ActionF. Non-steroid Hormone Action

Slide 9.8Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

1. Hormone binds to a membrane receptor

2. Hormone does not enter the cell

3. Sets off a series of reactions that activates an enzyme

4. Catalyzes a reaction that produces a second messenger molecule

5. Oversees additional intracellular changes to promote a specific response

Nonsteroid Hormone ActionNonsteroid Hormone Action

Slide 9.9Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Figure 9.1b

G. Control of Hormone ReleaseG. Control of Hormone Release

Slide 9.10Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

1. Hormone levels in the blood are maintained by negative feedback

2. A stimulus or low hormone levels in the blood triggers the release of more hormone

3. Hormone release stops once an appropriate level in the blood is reached

IV. Stimuli of Endocrine GlandsIV. Stimuli of Endocrine Glands

Slide 9.11Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

A. Endocrine glands are activated by other hormones

Figure 9.2a

Slide 9.12Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Figure 9.2b

B. Changing blood levels of certain ions stimulate hormone release

Slide 9.13Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

C. In some cases Nerve impulses stimulate hormone release

D. Most are under control of the sympathetic nervous system

Figure 9.2c

Location of Major Endrocrine OrgansLocation of Major Endrocrine OrgansSlide

9.15

Slide 9.14Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Figure 9.3

V. Hormone-Producing Tissues and V. Hormone-Producing Tissues and OrgansOrgans

Slide 9.39Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

A. Parts of the small intestine

B. Parts of the stomach

C. Kidneys

D. Heart

E. Many other areas have scattered endocrine cells

F. Endocrine Function of the F. Endocrine Function of the PlacentaPlacenta

Slide 9.40Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

1. Produces hormones that maintain the pregnancy

2. Some hormones play a part in the delivery of the baby

3. Produces HCG in addition to estrogen, progesterone, and other hormones

VI. Developmental Aspects of the VI. Developmental Aspects of the Endocrine System Endocrine System

Slide 9.41Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

A. Most endocrine organs operate smoothly until old age

1. Menopause is brought about by lack of efficiency of the ovaries

2. Problems associated with reduced estrogen are common

3.Growth hormone production declines with age

4. Many endocrine glands decrease output with age