Animal Tissues: Types, Locations, and Functions

• Four tissue types include: Epithelial, Connective, Muscle, and Nervous.
• Epithelial tissue covers body surfaces, lines cavities and organs, and forms glands.
• Connective tissue stabilizes, binds, and supports other tissues, including loose, dense, cartilage, bone, blood, and adipose tissues.
• Muscle tissue facilitates body movement and movement of fluids.
• Nervous tissue conducts nerve impulses, including neurons and neuroglia.

Tissue Location and Function

• Simple Squamous tissue facilitates diffusion in alveoli and blood vessels.
• Stratified Squamous tissue provides protection in the skin, mouth, esophagus, and vagina.
• Simple Cuboidal tissue enables absorption and secretion in kidney tubules, ovaries, and glands.
• Simple Columnar tissue is responsible for absorption and secretion in the digestive tract, respiratory tract, and uterus.
• Loose Connective Tissue (Areolar) binds and supports, containing fibroblasts.
• Dense Connective Tissue forms strong bands in tendons and ligaments.
• Cartilage supports and protects in the nose, ends of bones, joints, ear, and vertebrae.
• Bone supports, protects, allows movement, and stores minerals, with osteocytes in lacunae.
• Adipose Tissue is responsible for energy storage, insulation, and cushioning under the skin and around organs.
• Blood transports nutrients, gases, hormones, and wastes within blood vessels.
• Skeletal Muscle facilitates voluntary movement and attaches to the skeleton.
• Cardiac Muscle involuntarily pumps blood in the heart.
• Smooth Muscle involuntarily controls organ and blood vessel movement.
• Nervous Tissue, found in the brain, spinal cord, and nerves, contains neurons and neuroglia.

Glands

• Exocrine glands secrete into ducts leading to body surfaces, cavities, or organs, like sweat and oil glands.
• Endocrine glands lack ducts and secrete hormones into surrounding spaces.
• Glands are made of cuboidal epithelial tissue.

Cells in Tissues

• Bone tissue contains osteocytes in lacunae.
• Cartilage tissue contains chondrocytes in lacunae.
• Dense Connective Tissue contains fibroblasts.
• Areolar Connective Tissue contains fibroblasts.
• Nervous Tissue consists of neurons and neuroglial cells.

Muscle Tissue Types

• Skeletal Muscle is voluntary, striated, and attached to bones.
• Cardiac Muscle is involuntary, striated, and found in the heart.
• Smooth Muscle is involuntary, non-striated, and present in organs and blood vessels.

Cell Junctions

• Tight Junctions create leak-proof seals in the digestive tract.
• Adhesion Junctions provide flexibility and stretching in the skin.
• Gap Junctions enable quick communication in the heart muscle.

Membranes

• Mucous Membranes line passageways opening to the exterior.
• Serous Membranes line thoracic and abdominal cavities.
• Synovial Membranes line freely movable joint cavities.
• The Cutaneous Membrane, or skin, covers the body.

Body Cavities

• The Dorsal Cavity includes the Cranial Cavity, which contains the brain, and the Spinal Cavity, which contains the spinal cord.
• Ventral Cavity includes the Thoracic Cavity, containing the lungs (pleural cavity) and heart (pericardial cavity).
• Ventral Cavity also includes the Abdominal Cavity, containing digestive organs, separated by the diaphragm.

Integumentary System Functions

• The integumentary system protects against bacteria, UV radiation, and chemicals.
• It prevents water loss.
• It regulates body temperature.
• It synthesizes vitamin D.
• It receives stimuli such as touch, temperature, and pain.

Integumentary Components

• Skin is the main organ.
• Hair provides protection and insulation.
• Nails protect fingertips.
• Sweat Glands regulate temperature.
• Sebaceous (Oil) Glands lubricate skin and hair.
• Wax Glands are located in the ear.

Skin Layers

• Epidermis is the outer layer, composed of epithelial cells that are keratinized and protective.
• Dermis is the inner layer, composed of connective tissue and contains blood vessels, nerves, and glands.

Hypodermis

• Hypodermis (Subcutaneous Layer) is a loose connective tissue layer that anchors skin to underlying organs.

Melanocytes

• Melanocytes are cells in the epidermis that produce melanin, which protects skin from UV radiation.

Feedback Mechanisms

• Negative Feedback restores normal conditions by reversing a change.
• Positive Feedback enhances and amplifies changes.

Body Temperature Regulation

• Sensor: Thermoreceptors detect temperature change.
• Control Center: Hypothalamus in the brain.
• Effector: Sweat glands, blood vessels, and skeletal muscles.

Definitions

• Tissue: Group of similar cells working together.
• Apical Surface: Free surface of epithelial tissue.
• Basement Membrane: Anchors epithelial tissue to connective tissue.
• Exocrine Glands: Secrete into ducts.
• Endocrine Glands: Secrete hormones into blood.
• Loose Connective Tissue: Fewer fibers, more cells.
• Dense Connective Tissue: Tightly woven fibers, found in tendons/ligaments.
• Chondrocytes: Cartilage cells in lacunae.
• Osteocytes: Bone cells in lacunae.
• Lacunae: Small spaces in cartilage and bone where cells are found.
• Fibroblasts: Cells that produce fibers in connective tissue.
• Collagen Fibers: Provide strength in connective tissues.
• Elastic Fibers: Provide flexibility in connective tissues.
• Neurons: Conduct nerve impulses.
• Neuroglial Cells: Support and protect neurons.
• Organ: Structure composed of multiple tissues.
• Organ System: Group of organs working together.
• Diaphragm: Muscle that separates thoracic and abdominal cavities.
• Sebum: Oily substance secreted by sebaceous glands.
• Keratin: Protein in skin, hair, and nails for protection.
• Melanin: Pigment produced by melanocytes, protects from UV radiation.
• Dermis: Inner connective tissue layer of skin.
• Epidermis: Outer epithelial layer of skin.
• Hypodermis: Subcutaneous tissue beneath skin.
• Homeostasis: Maintenance of a stable internal environment.
• Sensor: Detects change in the environment.
• Control Center: Processes information (brain).
• Effector: Carries out response (muscles, glands).