Figure 3.17b Classification and functions of epithelia. Squamous Cuboidal Columnar (b) Classification based on cell shape
Figure 3.17c Classification and functions of epithelia. Diffusion and filtration Secretion in serous membranes Protection Secretion and absorption; ciliated types propel mucus or reproductive cells Protection; these tissue types are rare in humans Protection; stretching to accommodate distension of urinary structures (c) Function of epithelial tissue related to tissue type Number of layers Cell shape One layer: simple epithelial tissues More than one layer: stratified epithelial tissues Squamous Cuboidal Columnar Transitional
Figure 3.18a Types of epithelia and their common locations in the body. Nucleus of squamous epithelial cell Basement membrane Air sacs of lungs Nuclei of squamous epithelial cells (a) Diagram: Simple squamous Photomicrograph: Simple squamous epithelium forming part of the alveolar (air sac) walls (275×).
Figure 3.18c Types of epithelia and their common locations in the body. Basement membrane Mucus of a goblet cell Nucleus of simple columnar epithelial cell Simple columnar epithelial cells (c) Diagram: Simple columnar Photomicrograph: Simple columnar epithelium of the small intestine (575×).
Figure 3.18d Types of epithelia and their common locations in the body. (d) Diagram: Pseudostratified (ciliated) columnar Photomicrograph: Pseudostratified ciliated columnar epithelium lining the human trachea (560×). Basement membrane Pseudo- stratified epithelial layer Cilia Connective tissue
Figure 3.18e Types of epithelia and their common locations in the body. Basement membrane Connective tissue Stratified squamous epithelium (e) Diagram: Stratified squamous Photomicrograph: Stratified squamous epithelium lining of the esophagus (140×). Nuclei
Figure 3.18f Types of epithelia and their common locations in the body. Basement membrane Connective tissue Transi- tional epithelium Transitional epithelium (f) Diagram: Transitional Photomicrograph: Transitional epithelium lining of the bladder, relaxed state (270×); surface rounded cells flatten and elongate when the bladder fills with urine.
Figure 3.19b Connective tissues and their common body locations. Chondrocyte (cartilage cell) Chondrocyte in lacuna Matrix Lacunae Photomicrograph: Hyaline cartilage from the trachea (400×) (b) Diagram: Hyaline cartilage
Figure 3.19c Connective tissues and their common body locations. Chondro- cytes in lacunae Collagen fibers Chondrocytes in lacunae Collagen fiber Photomicrograph: Fibrocartilage of an intervertebral disc (150×) (c) Diagram: Fibrocartilage
Figure 3.19d Connective tissues and their common body locations. Ligament (d) Diagram: Dense fibrous Photomicrograph: Dense fibrous connective tissue from a tendon (475×) Collagen fibers Nuclei of fibroblasts Collagen fibers Tendon
Figure 3.19e Connective tissues and their common body locations. Mucosa epithelium Lamina propria Fibers of matrix Nuclei of fibroblasts Elastic fibers Collagen fibers Fibroblast nuclei (e) Diagram: Areolar Photomicrograph: Areolar connective tissue, a soft packaging tissue of the body (270×)
Figure 3.19f Connective tissues and their common body locations. Nuclei of fat cells Vacuole containing fat droplet Nuclei of fat cells (f) Diagram: Adipose Photomicrograph: Adipose tissue from the subcutaneous layer beneath the skin (570×)
Figure 3.19h Connective tissues and their common body locations. Photomicrograph: Smear of human blood (1290×) (h) Diagram: Blood Blood cells in capillary White blood cell Red blood cells Neutrophil (white blood cell) Red blood cells Monocyte (white blood cell)
Figure 3.22 Summary of the major functions and body locations of the four tissue types: epithelial, connective, muscle, and nervous tissues. Nervous tissue: Internal communication Brain, spinal cord, and nerves Muscle tissue: Contracts to cause movement Epithelial tissue: Forms boundaries between different environments, protects, secretes, absorbs, filters Connective tissue: Supports, protects, binds other tissues together Muscles attached to bones (skeletal) Muscles of heart (cardiac) Muscles of walls of hollow organs (smooth) Lining of GI tract organs and other hollow organs Skin surface (epidermis) Bones Tendons Fat and other soft padding tissue