BIO-120 Chapter 11-Human Organization PDF

Chapter 11: Human Organization Bio-120 11.1 Types of Tissues 1 Cells are composed of molecules; a tissue has similar types of cells; an organ contains several types of tissues; and several organs make up an organ system. A tissue is composed of similarly specializ...

Chapter 11: Human Organization Bio-120 11.1 Types of Tissues 1 Cells are composed of molecules; a tissue has similar types of cells; an organ contains several types of tissues; and several organs make up an organ system. A tissue is composed of similarly specialized cells that perform a common function in the body. 11.1 Types of Tissues 2 Four types of tissues in the human body. Epithelial: covers body surfaces and lines cavities. Connective: supports and binds body parts. Muscular: moves the body and its parts. Nervous: receives stimuli, processes that information, and conducts impulses. Epithelial Tissue 1 Epithelial Tissue. Tightly packed cells that form a continuous layer, also called an epithelium. Numerous functions. Usually protective. Secretion (glands). Absorption. Excretion. Filtration. Epithelial Tissue 2 On external surfaces, epithelial tissue protects the body from injury, drying out, and possible invasion by microbes. On internal surfaces, epithelial tissue carries out both protective and specific functions. A basement membrane of glycoproteins and collagen joins an epithelium to underlying connective tissue. Epithelial Tissue 3 Classified according to cell shape. Squamous epithelium: flattened cells. Cuboidal epithelium: cubed-shaped cells. Columnar epithelium: columnar-shaped cells; resembling rectangular pillars. Epithelial Tissue 4 Classified according to the number of layers in the tissue. Simple epithelium: single layer of cells. Stratified epithelium: multiple cell layer. Pseudostratified epithelium: appears to be layered but each cell touches basement membrane. Epithelial Tissue 5 Glandular epithelium secretes a product. Gland—can be single or multiple cells. Exocrine glands—secrete products into ducts. Endocrine glands—secrete product into bloodstream. Pancreas is both an exocrine and endocrine gland. Epithelial Tissue 6 top left ©Ed Reschke Epithelial Tissue 7 bottom middle ©Ed Reschke Epithelial Tissue 8 bottom right ©Ed Reschke Epithelial Tissue 9 bottom left ©Ed Reschke Epithelial Tissue 10 ©Ed Reschke Epithelial Tissue 11 ©Ed Reschke Junctions Between Epithelial Cells Tight junctions—form an impermeable barrier between cells. Gap junctions—allow small molecules to pass between cells and also strengthen connections. Adhesion junctions—act like rivets or “spot welds”; anchor tissues in place and increase their overall strength. Connective Tissue 1 Connective Tissue. Binds organs together. Provides support and protection. Fills spaces. Produces blood cells. Stores fat. Connective tissue cells are widely separated by a matrix, which is a noncellular material that varies in consistency. Solid, semisolid, or liquid. Connective Tissue 2 Composition of nonfluid matrix. Fibers: Collagen fibers: protein that gives flexibility and strength. Reticular fibers: thin, highly branched collagen fibers that form supporting network. Elastic fibers: contain elastin, a protein that is not as strong as collagen, but more elastic. Loose Fibrous and Dense Connective Tissues 1 Loose fibrous connective tissue. Supports epithelium and many internal organs. Forms a protective covering enclosing many internal organs. Muscles, blood vessels, and nerves. Found in the lungs, arteries, and urinary bladder. Loose Fibrous and Dense Connective Tissues 2 Dense fibrous connective tissue. Contains many collagen fibers packed together. Found in structures such as. Tendons—connect muscles to bones. Ligaments—connect bones to other bones. Both loose and dense connective tissue have cells called fibroblasts. Separated by a jelly-like matrix with collagen and elastic fibers. Loose Fibrous and Dense Connective Tissues 3 ©Ed Reschke Adipose Tissue and Reticular Connective Tissue 1 Adipose Tissue. Fibroblasts enlarge and store fat and become adipocytes. Used for: Energy storage. Insulation against heat loss or gain. Organ protection. Found beneath the skin, around the kidneys, and on surface of the heart. Adipose Tissue and Reticular Connective Tissue 2 ©Ed Reschke Adipose Tissue and Reticular Connective Tissue 3 Reticular Connective Tissue. Forms the supporting meshwork of lymphatic tissue. Found in lymph nodes, spleen, thymus, and bone marrow. Cartilage 1 Cartilage. Specialized form of dense fibrous connective tissue. Commonly forms smooth surfaces that enable bones to slide against one another in joints. Cells lie in small chambers called lacunae, separated by solid but flexible matrix. Three types of cartilage. Hyaline, elastic, and fibrocartilage. Cartilage 2 Hyaline: the most common type. Contains very fine collagen fibers. Found in the nose and ends of long bones and ribs. Forms rings in the walls of respiratory passages. Forms fetal skeleton that later becomes bone. Elastic: higher proportion of elastic fibers, so more flexible. Framework of outer ear. Fibrocartilage: contains strong collagen fibers. Found in structures that withstand tension and pressure such as the pads between vertebrae. Cartilage 3 ©Ed Reschke Bone 1 Bone. The most rigid connective tissue. Extremely hard matrix, formed from: Calcium salts deposited around collagen fibers. Give bone rigidity. Protein fibers. Provide elasticity and strength. Two types of bone tissue. Compact. Spongy. Bone 2 Compact bone. Forms shafts of long bones. Consists of cylindrical structures called osteons. Central canal of each osteon surrounded by rings of hard matrix. Bone cells located in spaces called lacunae between rings of hard matrix. Spongy bone. Contains many bony bars and plates, separated by irregular spaces. Found in ends of long bones. Though lighter, still designed for strength. Bone 3 ©Ed Reschke Blood 1 Blood. Unlike other types of connective tissue, the matrix (that is plasma) is not made by the cells. Functions. Transports nutrients and oxygen to, and removes carbon dioxide and wastes from, interstitial fluid (fluid between cells). Helps distribute heat. Plays role in fluid, ion, and pH balance. Protects against disease. Blood clotting protects against fluid loss. Blood 2 Components of blood. Plasma—55% of volume. Variety of inorganic and organic substances dissolved or suspended in water. Formed elements—45% of volume. Red blood cells (erythrocytes). White blood cells (leukocytes). Platelets (thrombocytes). Blood 3 TABLE 11.1 Components of Blood Plasma. Water (90–92% of total) Solutes (8–10% of total) Inorganic ions (electrolytes) Na+, Ca2+, K+, Mg2+, Cl−, HCO3−,HPO42−, SO42− Gases O2, CO2 Plasma proteins Albumin, globulins, fibrinogen, transport proteins Organic nutrients Glucose, lipids, phospholipids, amino acids, etc. Nitrogen-containing waste Urea, ammonia, uric acid products Regulatory substances Hormones, enzymes Blood 4 Red blood cells (erythrocytes). Small, biconcave, disk-shaped cells that lack a nucleus. Contain hemoglobin for transport of oxygen. Complex of four units; each contains globin protein and heme group. Heme group contains iron that links to oxygen. White blood cells (leukocytes). Larger cells with a nucleus. Fight infection in different ways. By phagocytosis or adaptive immunity, which includes antibody production. Blood 5 Platelets (thrombocytes). Cell fragments involved with blood clotting. Help to form a plug that seals damaged blood vessels. Injured tissues release molecules to stimulate the clotting process. Blood 6 Muscular Tissue 1 Muscular tissue. Composed of cells called muscle fibers. Muscle fibers contain actin and myosin filaments. Interaction accounts for sliding movements. Types of muscle tissues. Skeletal. Smooth (visceral). Cardiac. Muscular Tissue 2 Skeletal muscle. Cylindrical, long, and multinucleated due to fusion of several cells into a fiber. Striated due to alternating light and dark bands. Usually attached by tendons to bones of the skeleton. Contraction. under voluntary control. causes bones of the skeleton to move at joints. Muscular Tissue 3 Smooth muscle. Cells lack striations; smooth appearance. Occurs in walls of blood vessels and viscera (intestine, stomach, and other internal organs and blood vessels). Cells are spindle shaped, with a single nucleus. Nuclei form an irregular pattern. Not under voluntary control. Muscular Tissue 4 Cardiac muscle. Found only in the walls of the heart. Has branching, striated cells, each with a single nucleus. Cells are separate and individual but are bound end to end at intercalated disks. Gap junctions promote the flow of electrical impulses when the heart muscle contracts. Not under voluntary control. Muscular Tissue 5 ©Ed Reschke Muscular Tissue 6 ©McGraw-Hill Education/Dennis Strete, Muscular Tissue 7 ©Ed Reschke Nervous Tissue 1 Nervous tissue contains neurons (nerve cells) and is present in the brain and spinal cord. A neuron is a specialized cell with three structures. Dendrites—processes that conduct signals toward the cell body. Cell body—contains the cytoplasm and nucleus. Axon—a process that conducts nerve impulses away from the cell body. May have myelin sheath to increase speed. Nervous Tissue 2 Neuroglia. Outnumber neurons nine to one. Support and nourish neurons. Four types in the brain. Microglia: engulf bacterial and cellular debris. Astrocytes: provide nutrients. Oligodendrocytes: form myelin sheaths in brain. Schwann cells: form myelin sheaths outside the brain. Ependymal cells: line fluid-filled spaces of brain and spinal cord. Nervous Tissue 3 Nervous Tissue 4 ©Ed Reschke 11.2 Body Cavities and Body Membranes 1 Referring to anatomical parts of humans, certain standard terms are used based on the upright position (standing position). Ventral or anterior means toward the front. Dorsal or posterior means toward the back. Superior means toward the head. Inferior means toward the feet. Medial is closer to the body midline. Lateral is away from the body midline. 11.2 Body Cavities and Body Membranes 2 Human body divided into cavities. Ventral Cavity or Coelom. Thoracic cavity. Lungs and heart. Abdominal cavity. Separated from thoracic cavity by diaphragm. Stomach, liver, spleen, gallbladder, and most of the small and large intestines. Pelvic cavity. Bladder, rectum, internal reproductive organs. 11.2 Body Cavities and Body Membranes 3 Dorsal Cavity. Cranial cavity—within the skull. Contains the brain. Vertebral canal—made of the vertebrae. Contains the spinal cord. 11.2 Body Cavities and Body Membranes 4 11.2 Body Cavities and Body Membranes 5 Body Membranes 1 Body membranes line cavities and the internal spaces of organs and tubes that open to the outside. Mucous membranes. Line tubes of the digestive, respiratory, urinary, and reproductive systems. Made of an epithelium overlying loose fibrous connective tissue. Goblet cells produce mucus. Protective function. Body Membranes 2 Serous Membranes. Line thoracic and abdominal cavities. Made of epithelium and loose fibrous connective tissue. Secrete watery fluid for lubrication. Carry specific names according to location. Pleurae—lines thoracic cavity and lungs. Pericardium—encloses heart. Peritoneum—lines abdominal cavity and covers organs. Mesentery supports abdominal organs and attaches them to abdominal wall. Body Membranes 3 Synovial membranes. Made of loose connective tissue. Line freely movable joints. Secrete synovial fluid. Meninges. Membranes in the dorsal cavity. Protect brain and spinal cord. Made of connective tissue. 11.3 Organ Systems 1 The human body is organized into 11 organ systems. Integumentary Skeletal Cardiovascular Muscular Lymphatic and Immune Nervous Digestive Endocrine Respiratory Urinary Reproductive 11.3 Organ Systems 2 11.3 Organ Systems 3