Download presentation
Presentation is loading. Please wait.
1
The Tissue Level of Organization
2
Learning Objectives Identify the four major tissue types and describe their functions. Describe the relationship between form and function for each tissue type. Discuss the types and functions of epithelial tissues. Compare the structure and function of connective tissues.
3
Learning Objectives Explain the structure and function of the four types of membrane. Describe the three types of muscle tissue and the structural features of each. Discuss the basic structure and role of neural tissue.
4
SECTION 4-1 Tissues of the Body: An Introduction
5
Tissues and tissue types
Tissues are: Collections of specialized cells and cell products organized to perform a limited number of functions Histology = study of tissues The four tissue types are: Epithelial Connective Muscular Nervous
6
Epithelial tissue Includes glands and epithelium Glands are secretory
Is avascular Forms a protective barrier that regulates permeability Cells may show polarity
7
Functions of epithelium
Physical protection Control permeability Provide sensation Produce specialized secretions
8
Specializations of epithelium
Perform secretory functions Perform transport functions Maintain physical integrity Ciliated epithelia move materials across their surface
9
Figure 4.1 The Polarity of Epithelial Cells
10
Maintaining the integrity of epithelium
Cells attach via cell adhesion molecules (CAM) Cells attach at specialized cell junctions Tight junctions Desmosomes Gap junctions
11
Figure 4.2 Intercellular connections
PLAY Animation: Intercellular connections Figure 4.2
12
Structure of typical epithelium
Basal lamina attaches to underlying surface Lamina lucida Lamina densa Germinative cells replace short-lived epithelial cells
13
Classification of epithelia
Number of cell layers Simple Stratified Shape of apical surface cells Squamous Cuboidal Columnar
14
Figure 4.3 Squamous Epithelia
15
Figure 4.4 Cuboidal Epithelia
Figure 4.4a
16
Figure 4.4 Cuboidal Epithelia
Figure 4.4b
17
Figure 4.4 Transitional Epithelium
Figure 4.4c
18
Figure 4.5 Columnar Epithelia
Figure 4.5a
19
Figure 4.5 Columnar Epithelia
Figure 4.5b
20
Figure 4.5 Columnar Epithelia
21
Glandular epithelia Exocrine glands
Secrete through ducts onto the surface of the gland Endocrine glands Release hormones into surrounding fluid
22
Glandular secretions can be:
Merocrine (product released through exocytosis) Apocrine (involves the loss of both product and cytoplasm) Holocrine (destroys the cell)
23
Figure 4.6 Mechanisms of Glandular Secretion
PLAY Animation: Mechanisms of glandular secretion Figure 4.6
24
Glands Unicellular Individual secretory cells Multicellular
Organs containing glandular epithelium Classified according to structure
25
Figure 4.7 A Structural Classification of Exocrine Glands
26
SECTION 4-3 Connective Tissues
27
Connective tissue functions:
Establishing a structural framework Transporting fluids and dissolved materials Protecting delicate organs Supporting, surrounding and interconnecting tissues Storing energy reserves Defending the body from microorganisms
28
Figure 4.8 A Classification of Connective Tissues
29
Connective tissues contain
Specialized cells Matrix Composed of extracellular protein fibers and a ground substance
30
Connective tissue proper
Contains varied cell populations Contains various fiber types A syrupy ground substance
31
Fluid connective tissue
Contains a distinctive cell population Watery ground substance with dissolved proteins Two types Blood Lymph
32
Supporting connective tissues
Less diverse cell population Dense ground substance Closely packed fibers Two types Cartilage Bone
33
Connective tissue proper
Contains fibers, a viscous ground substance, and a varied cell population Fibroblasts Macrophage Adipocytes Mesenchymal cells Melanocytes Mast cells Lymphocytes Microphages
34
Connective tissue proper
Three types of fiber Collagen fibers Reticular fibers Elastic fibers
35
Connective tissue proper
Classified as loose or dense Loose Embryonic mesenchyme, mucous connective tissues Areolar tissue Adipose tissue Reticular tissue Dense Dense regular CT Dense irregular CT
36
Figure 4.9 The Cells and Fibers of Connective Tissue Proper
37
Figure 4.10 Connective Tissue in Embryos
38
Figure 4.11 Adipose and Reticular Tissues
39
Figure 4.12 Dense Connective Tissues
Figure 4.12a
40
Figure 4.12 Dense Connective Tissues
Figure 4.12b
41
Figure 4.12 Dense Connective Tissues
Figure 4.12c
42
Fluid connective tissues
Distinctive collections of cells in a fluid matrix Blood Formed elements and plasma Red blood cells, white blood cells and platelets Arteries carry blood away, veins carry to the heart Capillaries allow diffusion into the interstitial fluid Lymph Interstitial fluid entering the lymphatic vessels
43
Figure 4.13 Formed Elements of the Blood
44
Supporting connective tissues
Cartilage and bone support the rest of the body Cartilage Grows via interstitial and appositional growth Matrix is a firm gel containing chondroitin sulfate Cells called chondrocytes Cells found in lacunae Perichondrium separates cartilage from surrounding tissues Three types: hyaline, elastic and fibrocartilage
45
Figure 4.15 The Perichondrium and Types of Cartilage
Figure 4.15a, b
46
Figure 4.15 The Perichondrium and Types of Cartilage
Figure 4.15c
47
Figure 4.15 The Perichondrium and Types of Cartilage
Figure 4.15d
48
Bone, or osseus tissue Has osteocytes
Depend on diffusion through canaliculi for nutrients Little ground substance Dense mineralized matrix Surrounded by periosteum
49
Figure Bone Figure 4.16
50
SECTION Membranes
51
Membranes are simple organs
Form a barrier Composed of epithelium and connective tissue Four types Cutaneous Synovial Serous Mucous
52
Figure Membranes Figure 4.17a-d
53
Mucous membranes Line cavities that communicate with the exterior
Contain lamina propria
54
Serous membranes Line sealed internal cavities Form transudate
55
Cutaneous membrane Covers the body surface Synovial membrane Incomplete lining within joint cavities
56
SECTION 4-5 The Connective Tissue Framework of the Body
57
Organs and systems are interconnected
Network of connective tissue proper consisting of Superficial fascia Deep fascia Subserous fascia
58
Figure The Fasciae Figure 4.18
59
SECTION 4-6 Muscle Tissue
60
Muscle tissue Specialized for contraction Three types Skeletal Cardiac
Smooth
61
Figure Muscle Tissue Figure 4.19a
62
Figure Muscle Tissue Figure 4.19b
63
Figure Muscle Tissue Figure 4.19c
64
Skeletal muscle Cells are multinucleate Striated voluntary muscle
Divides via satellite cells
65
Cardiac muscle Cardiocytes occur only in the heart
Striated involuntary muscle Relies on pacemaker cells for regular contraction
66
Smooth muscle tissue Non-striated involuntary muscle
Can divide and regenerate
67
SECTION 4-7 Neural Tissue
68
Neural tissue Conducts electrical impulses
Conveys information from one area to another
69
Neural tissue cells Neurons Transmit information Neuroglia
Support neural tissue Help supply nutrients to neurons
70
Figure Neural Tissue Figure 4.20
71
Neural anatomy Cell body Dendrites Axon (nerve fiber)
Carries information to other neurons
72
SECTION 4-8 Tissue Injuries and Aging
73
Inflammation and regeneration
Injured tissues respond in coordinated fashion Homeostasis restored by inflammation and regeneration
74
Inflammatory response
Isolates injured area Damaged cells, tissue components and dangerous microorganisms removed Infection avoided Regeneration restores normal function
75
Figure 4.21 An Introduction to Inflammation
76
Aging and tissue repair
Change with age Repair and maintenance less efficient Structure altered Chemical composition altered
77
Aging and cancer incidence
Incidence of cancer increases with age 70-80% of all cases due to exposure to chemicals or environmental factors
78
Figure 4.22 Changes in a Tissue under Stress
79
You should now be familiar with:
The four major tissue types and their functions. The relationship between form and function for each tissue type. The types and functions of epithelial tissues. The structure and function of connective tissues. The structure and function of the four types of membrane. The three types of muscle tissue and the structural features of each. The basic structure and role of neural tissue.
Similar presentations
