Animal Structure and Function: An Introduction

1. Animal Structure and Function: An Introduction Chapter 38

2. KEY CONCEPTS • Structure and function are closely linked at every level of organization

3. Learning Objective 1 • Compare the structure and function of the four main kinds of animal tissues: epithelial, connective, muscle, and nervous

4. Tissue • A group of similarly specialized cells • Associated to perform one or more functions

5. Epithelial Tissue(Epithelium) • A continuous layer (sheet) of cells • covering a body surface • lining a body cavity • Functions in protection, absorption, secretion, or sensation

6. Connective Tissue 1 • Relatively few cells separated by intercellular substance • fibers scattered throughout a matrix • Intercellular substance fibers • collagen fibers • elastic fibers • reticular fibers

7. Connective Tissue 2 • Contains specialized cells • such as fibroblasts and macrophages • Functions: • joins other body tissues • supports body and organs • protects underlying organs

8. Muscle Tissue • Consists of cells specialized to contract • Each cell is an elongated muscle fiber • many contractile units (myofibrils)

9. Nervous Tissue • Neurons • elongated cells • specialized for transmitting impulses • Glial cells • support and nourish neurons

10. Learning Objective 2 • Compare the structure and function of the main types of epithelial tissue

11. Epithelial Tissue • Epithelial cell shapes • squamous, cuboidal, columnar • Epithelial tissue structure • simple, stratified, pseudostratified • (See Table 38-1)

12. Simple Squamous Epithelium • Lines blood vessels and air sacs in lungs • Permits exchange of materials by diffusion

13. Simple Cuboidal and Columnar Epithelia • Line passageways • Specialized for secretion and absorption

14. Stratified Squamous Epithelium • Forms outer layer of skin • Lines passageways into the body • Provides protection

15. Pseudostratified Epithelium • Lines passageways • Protects underlying tissues

16. Glands 1 • Specialized epithelial tissue • Goblet cells • unicellular exocrine glands that secrete mucus

17. Glands 2 • Exocrine glands • secrete product through a duct onto exposed epithelial surface • Endocrine glands • release hormones into interstitial fluid or blood

18. Glands

19. Unicellular glands (goblet cells) Cilia Basement membrane (a) Goblet cells. Skin (c) Parotid salivary gland. (b) Sweat gland. Fig. 38-1, p. 809

20. Membranes • Epithelial membrane • sheet of epithelial tissue • layer of underlying connective tissue • Mucous membrane • lines cavity that opens to outside of body • Serous membrane • lines cavity that does not open to the outside

21. Learning Objective 3 • Compare the main types of connective tissue • Summarize their functions

22. Connective Tissues • Cells embedded in intercellular substance • microscopic collagenfibers, elastic fibers, reticular fibers (thin branched fibers) • scattered through a matrix (thin gel of polysaccharides)

23. Loose Connective Tissue • Consists of fibers running in various directions through a semifluid matrix • Flexible tissue forms a covering for nerves, blood vessels, and muscles

24. Dense Connective Tissue • Stronger, less flexible than loose connective tissue • Collagen fibers arranged in definite pattern • Forms • tendons (connect muscles to bones) • ligaments (connect bones to bones)

25. Dense Connective Tissue

26. Elastic Connective Tissue • Consists of bundles of parallel elastic fibers • Found in lung tissue, walls of large arteries

27. Reticular Connective Tissue • Consists of interlacing reticular fibers • Forms support framework for many organs

28. Adipose Tissue • Consists of fat cells • Found with loose connective tissue in subcutaneous tissue

29. Cartilage and Bone • Form skeletons of vertebrates • Cartilage consists of chondrocytes • in lacunae (small cavities in hard matrix) • nonvascular • Osteocytes • secrete and maintain bone matrix • vascular

30. Cartilage and Bone • Cartilage • Bone

31. Bone

32. (a) The human skeleton consists mainly of bone. (b) A bone is cut open, exposing its internal structure. Fig. 38-2ab, p. 814

33. BloodandLymph • Circulating tissues • fluid intercellular substances • Help parts of an animal communicate with one another

34. Learning Objective 4 • Contrast the three types of muscle tissue and their functions

35. Skeletal Muscle • Striated and under voluntary control • Elongated, cylindrical fibers with several nuclei • Skeletal muscles contract, move parts of the body

36. Cardiac Muscle • Striated, contractions are involuntary • Elongated, cylindrical fibers branch and fuse; one or two central nuclei • Muscle contracts, heart pumps blood

37. Smooth Muscle • No striations, contractions involuntary • Elongated, spindle-shaped fibers with a single central nucleus • Smooth muscle moves body organs (example: pushes food through digestive tract)

38. Muscle Tissues

39. Learning Objective 5 • How does the structure of the neuron relate to its function?

40. Neuron • Elongated cell • Receives and transmits information • Synapse • a junction between neurons

41. Neuron • Dendrites • receive signals • transmit signals to cell body • Axon • transmits signals away from cell body • to other neurons, muscles, glands

42. Neuron

43. Neurons Dendrite Nuclei of glial cells Axon 100 µm Fig. 38-3, p. 817

44. KEY CONCEPTS • The main types of tissues in a complex animal are epithelial, connective, muscle, and nervous

45. Learning Objective 6 • Describe the organ systems of a mammal • Summarize the homeostatic actions of each organ system

46. Organ Systems • Tissues and organs working together • In mammals, 11 organ systems work together in the organism • Each organ system functions to maintain homeostasis

47. 11 Organ Systems Integumentary Respiratory Skeletal Urinary Muscular Nervous Digestive Endocrine Cardiovascular Reproductive Immune (lymphatic)

48. 11Organ Systems

49. 11Organ Systems

50. Insert “Human organ systems” organ_systems_v2.swf