1. Introduction to Animal Structure and Function
Chapter 40 Notes
Introduction to Animal Structure and Function

2. Concept 40.1 Anatomy: the study of the structure of an organism
Physiology: study of the functions an organism performs
Structure and function are interrelated

3. Concept 40.1 Physical laws constrain animal form
- ex. an amoeba the size of a human could not move material across its membrane fast enough
- ex. the laws of hydrodynamics constrain the shapes that are possible for aquatic animals to swim fast

4. Concept 40.1

5. Concept 40.2
In most animals, combinations of various tissues make up organs, and groups of organs that work together form organ systems.
Tissues: groups of cells with a common structure and function
- epithelial, connective, nervous, and muscle

6. Concept 40.2 Epithelial tissue:
- covers the outside of the body and lines the organs within the body
- cells are held together by tight junctions
- epithelial cells are classified by the number of cell layers and the shape of the cells

7. Concept 40.2

8. Concept 40.2

9. Concept 40.2 Connective tissue:
- functions to bind and support other tissues
- connective tissue fibers are composed of proteins
- ex. loose connective tissue, adipose tissue, fibrous connective tissue, cartilage, bone, and blood

10. Concept 40.2

11. Concept 40.2

12. Concept 40.2 Nervous tissue:
- senses stimuli and transmits signals from one part of the animal to another
- nerve cells, or neurons, are specialized to transmit signals

13. Concept 40.2

14. Concept 40.2 Muscle tissue:
- composed of long cells called muscle fibers that are capable of contracting when stimulated by nerve impulses
- skeletal (striated) muscle, cardiac muscle, and smooth muscle

15. Concept 40.2

16. Concept 40.2

17. Concept 40.5
Many animals tend to maintain relatively constant conditions in their internal environment, even when their external environment changes
- ex. body temp = 37oC; pH = 7.4
Animals maintain homeostasis, or internal balance within their systems

18. Concept 40.5
Homeostatic control systems have three functional components
- the receptor detects a change
- the control center processes information
- the effector directs the appropriate response

19. Concept 40.5
Negative feedback: a change in the variable being monitored triggers the control mechanism to counteract further change
- ex. control of the temperature of a room
- ex. control of body temp.

20. Concept 40.5

21. Concept 40.5

22. Concept 40.5
Positive feedback: a change in some variable that triggers mechanisms that amplify rather than reverse change
Regulated change: some are cyclical such as in hormone levels in women while others are reactions to challenges of the body (like infections).