Chapter 11: Introduction to Human Organization PDF

Anatomy is the study of the structure of an organism. Knowledge of a structure provides insight into what it does and how its works. Structure = Anatomy Anatomy = Structure  Physiology is the...

Anatomy is the study of the structure of an organism. Knowledge of a structure provides insight into what it does and how its works. Structure = Anatomy Anatomy = Structure  Physiology is the study of the functions an organism performs. Knowledge of the function of a structure provides insight about its construction. Physiology= functions Functions = physiology  Animals are multicellular organisms with several levels of biological organization: 1. specialized cells are grouped into tissues. 2. combinations of various tissues make up functional units called organs 3. groups of organs that work together form organ systems.  Tissues are groups of cells with a common structure and function.  Different types of tissues have different structures that are especially suited to their functions.  Tissues are classified into four main categories: 1. epithelial tissue 2. connective tissue 3. nervous tissue 4. muscle tissue Epithelial tissue covers the outside of the body and lines organs and cavities within the body. Epithelial tissue occurs in sheets of tightly packed cells that are classified by shape and # of layers (stratification). SHAPE and Layers  Shape and layer ANATOMY: Epithelium tissues: shape and number of cell layers 1) Cell Layer A).Simple epithelium has a single layer of cells B). Stratified epithelium has multiple cell layers. 2 Cell Shape A). Cuboidal (like dice) B). Columnar (like rectangles or bricks C). Squamous (flat like floor tiles) Fig. 40.1  Physiology of Epithelial Tissue:  1). Protection: barrier against mechanical injury, invasive microorganisms, and fluid loss.  2) Secretion (glands): absorb or secrete chemical solutions.  3). Mucus: Lines the cavity of the digestive and respiratory tracts and forms a membrane that secretes a slimy solution called mucus that lubricates the surface and keeps it moist.  4). Absorption: ex: nutrients from the small intestine  5). Diffusion: gases in the lungs  6). Filtration: molecules from kidneys/ Fluid CT: blood Connective tissues have a sparse population of cells and protein fibers scattered through an extracellular matrix. 1.Matrix: solid, semisolid or jelly, or liquid foundation 2.Fibers: web of protein fibers consisting of collagen, elastic or reticular fibers. 3.Cells: various types that in most cases secrete the matrix. (ex: fibroblasts, macrophages, ) Connective tissue fibers: ◦ Collagen fibers are made of white collagen protein which are flexible but strong. They are not elastic, but do not tear easily when pulled lengthwise. ◦ Elastic fibers are long yellow threads of the protein elastin and are not as strong as collagen, but more elastic. ◦ Reticular fibers are very thin and branched collagen fibers and form a supportive network of woven fabric that joins connective tissue to adjacent tissues. Types of connective tissues in vertebrates: Loose fibrous tissue Dense fibrous tissue Adipose tissue Cartilage Bone Blood and lymph Each has a structure correlated with its specialized function. (A&P!!!) Fig. 40.2 Physiology Overview: 1.Fibrous CT: Binds and supports other tissues and organs and/or stores fat (loose, dense & adipose) 2.Supportive CT: Provides support and protection (bones & hyaline cartilage) 3.Fluid CT: distributes nutrients and oxygen (blood & lymph) 1). Loose Fibrous connective tissue A). Physiology: supports and protects epithelium and many internal organs holding organs in place. B). Anatomy: Fibers: all three fiber types: collagen, elastic and reticular Matrix: jelly-like Cells: ◦ Fibroblasts secrete the protein ingredients of the extracellular fibers. ◦ Macrophages are amoeboid cells that roam the maze of fibers, engulfing bacteria and the debris of dead cells by phagocytosis. 2. Dense Fibrous Connective Tissue A). Physiology: ◦ Tendons: attaching muscles to bones ◦ Ligaments: joining bones to bones at joints. B). Anatomy: is dense, due to its large number of collagenous fibers.  Fibers: collagen organized into parallel bundles, an arrangement that maximizes non-elastic strength  Matrix: jelly-like  Cells: Fibroblasts 3. Adipose tissue (specialized loose CT) A). Physiology Energy: Fat is stored in adipose cells and used for energy Protection: surrounds organs (ex: kidney) Insulation: to maintain body temperature. B). Anatomy: Fibres: reticular Matrix: very little space Cells: Adipocytes swell when fat is stored and shrink when fat is used as fuel 4. Cartilage (Supportive CT) A). Physiology: A strong yet somewhat flexible support material in certain locations, such as the nose, ears, ribs, and vertebral disks. B). Anatomy: Fibers: collagenous & elastic fibers Matrix: gel-like; protein-carbohydrate matrix.  Cells: Chondrocyte cells lie in small chambers called lacuna.  Fibrocartilage: Elastic: (outer ear): mostly Vertebrae pads & knee joint): Elastic fibers & more flexible strong collagen fibers Hyaline: (nose, ribs): firm and flexible, fine collagen fibers 5. Bone: (Supportive CT) A). Physiology: Support and protection: most vertebrates skeleton is made of bone. Mineral Storage (Ca+, Mg+…) Blood Cell Formation B). Anatomy: Fibers collagen fibers strength and elasticity Matrix: calcium and inorganic salts harden the matrix  Cells: Osteocytes within lacuna 1. Compact Bone: (shafts of long bones) 2. Spongy Bone: (end of long bones) 6. Blood ( Fluid CT) A). Physiology: Transports respiratory gases, ions, nutrients and wastes Regulation: body temperature, pH, salts Helps protect against disease B). Anatomy: Fibers: soluble proteins (ex: fibrinogen) Matrix: liquid plasma, consisting of water, salts, and a variety of dissolved proteins. Cells: Erythrocytes (red blood cells), leukocytes (white blood cells) and thrombocytes (platelets; cell fragments) that function in blood clotting A). Anatomy: Cells are called muscle fibers that contract when stimulated by nerve impulses. Muscle fibers contain contractile proteins actin (microfilaments) and myosin filaments. Fibers are cylindrical and long and depend on the type of muscle (there are 3) B). Physiology: Skeletal:Voluntary movement Cardiac: Involuntary -> pumping of blood  Smooth: Involuntary-> aids the movement of substances in lumens (cavities) of the body  Three types of Muscular Tissue Fig. 40.4 Physiology: attached to bones by tendons and responsible for voluntary movement of body parts. Anatomy: cylindrical, long, overlapping filaments striped or striated appearance Multinucleated Smooth muscle: (no striations) Physiology: involuntary body activities such as churning of the stomach and constriction of arteries. Acts involuntarily to aid the movement of substances in lumens (cavities) of the body They contract more slowly than skeletal muscles but can remain contracted longer. found in the walls of the digestive tract, urinary bladder, arteries, and other internal organs. Anatomy: cells are spindle-shaped and not striated One nucleus/cell in irregular patterns Physiology:  involuntarily contraction pumps blood & accounts for heart beat Anatomy: striated like cardiac muscle, but cardiac cells are branched. Single, central placed nucleus Cells are joined by intercalated disks, which relay signals from cell to cell during a heartbeat. A). Physiology: Conducts impulses senses stimuli, interprets and transmits signals from one part of the animal to another. B). Anatomy: Neurons: dendrites, cell body and an axon. Neurolgia: cells that support and nourish neurons Fig. 40.3 1. Ventral Cavity (divided by the diaphragm)  Thoracic cavity  Lungs  Heart  Abdominal cavity  Visceral organs  Bladder  Reproductive organs 2. Dorsal Cavity  Cranial cavity  Brain  Vertebral Canal  Spinal cord  vertebrae 1.Mucous Membranes: made of epithelium cells overlying loose fibrous connective tissues lines the digestive, respiratory, urinary and reproductive systems goblet cells produce mucous mucous protects the body from bacteria and viruses. 2. Serous Membranes: composed of epithelium and loose fibrous connective tissues lines the thoracic and abdominal cavitites secrete a watery fluid for lubrication, support of internal organs, and prevent infections  NAME: according to location: pleurae (line lungs) pericardium (line heart) and peritoneal lines the abdominal cavity 3. Synovial membranes: composed of loose connective tissue line joint cavities secrete synovial fluid for lubricating bones. 4.Meninges: composed of connective tissue Line the dorsal cavity (brain and vertebral canal)  protect the brain and spinal cord.  Organ systems carry out the major body functions of most animals.  Each organ system consists of several organs and has specific functions.