Chapter 20b: Animal Structure and Function

Question 1

*

How does exhange happen in complex animals?

Answer 1

• Some organ systems (like in humans) rely on exchange surfaces within the body - evolved branched or folded surfaces.
• Material exchange between blood and cells must go through interstitial fluid.

Question 2

Interstitial fluid

Answer 2

An aqueous solution that surrounds body cells and through which materials pass back and forth between the blood and the body tissues.

Question 3

How are organ systems interdependent?

Answer 3

• they work together to perform life’s functions.
• An organism is a whole that is greater than the sum of its parts.

Question 4

The 11 organ systems

Answer 4

1. *Circulatory
2. Digestive system
3. Endocrine
4. Integementary
5. Lymphatic
6. • Muscular
7. • Nervous
8. • Reproductive
9. • Respiratory
10. • Skeletal
11. • Urinary

Question 5

The Integementary System

Answer 5

Functions: protect body against damage.
Organs: hair, nails, skin
* Epidermis (outermost layer): stratified squamous epithelium; replenished continuously
* Dermis (inner layer): fibrous connective tissue; contains glands, blood vessels, hair follicles, muscles, and sensory receptors.
* Hypodermis(beneath the skin): adipose tissue

Question 6

The Skeletal and Muscular Systems

Answer 6

Organs: muscles, bones
Function: Skeletal system: structural supports the body. Muscular system: helps maintain body temperature. Both work together to enable movement.

Question 7

The Nervous and Endocrine System

Answer 7

Functions: communication between and coordination of all the body systems.
The endocrine system produces hormones and regulates bodily processes.
The nervous system detects and processes sensory info; coordinates bodily responses.
Organs: brain, thyroid gland.

Question 8

Circulatory System

Answer 8

Function: delivers oxygen and nutrients to tissue, carries waste away from tissues.
Organs: Heart, blood vessels.

Question 9

The Lymphatic and Immune System

Answer 9

Function: lymphatic system: returns fluid to blood. Immune system: works with the lymphatic system to defend the body against pathogens.

Question 10

Respiratory System

Answer 10

Function: supplies the body with oxygen and disposes of carbon dioxide.
Organs: lungs, trachea.

Question 11

Digestive System

Answer 11

Function: absorbs nutrients into bloodstream removes waste from undigested food.
Organs: stomach, intestines.

Question 12

Urinary System

Answer 12

Function: controls water balance and blood pH in the body, and removes wastes from blood.
Organs: kidneys, ureter.

Question 13

Reproductive System

Answer 13

Function: produces offspring and sex hormones.
Organs: ovaries, uterus.

Question 14

Which organ systems work to maintain homestasis?

Answer 14

• Nervous system detects changes and sends nerve impulses to counteract the change.
• Endocrine system responds by secreting hormones.

Question 15

How do feedback loops maintain homestasis?

Answer 15

• A sensor detects change.
• Control center receives signals from the sensor and coordinates a response.
• An effector is tissue, organ, or cell that exerts a response according to the signals sent by the control center.

Question 16

Negative and positive feedback

Answer 16

Negative feedback: any control mechanism that reduces or reverses a change in the internal environment.

Positive feedback: any control mechanism that amplifies a change in the internal environment.

Most of the control mechanisms of homeostasis are based on negative feedback.

Question 17

How are blood sugar levels controlled?

Answer 17

Insulin: stimulates cells to take glucose out of the blood and store it in cells
* Decreases blood glucose

Glucagon: stimulates cells to release glucose into the blood
* Increases blood glucose

Both are pancreatic hormones

See chart