LostMice Posted January 2, 2019 Report Share Posted January 2, 2019 Organization of vertebrate body There are four levels of organization Cells Tissues Organs Organ Systems Bodies of vertebrates are composed of different cell types Humans have 210 Tissues Groups of cells that are similar in structure and function 3 fundamental embryonic tissues are called germ layers Endoderm, mesoderm, and ectoderm In adult vertebrates, there are four primary tissues Epithelial, Connective, muscle, & nerve Organs Combinations of different tissues that form a structural and functional unit Organ systems Groups of organs that cooperate to perform the major activities of the body Vertebrate body contains 11 percent of the human body General body plan of all vertebrates is essentially a tube within a tube Inner tube - digestive tract Outer tube- Main vertebrate body Supported by a skeleton Outermost layer - skin and its accessories 2 main body cavities Dorsal body cavity Forms within skull and vertebrate Ventral body cavity Bounded by the rib cage and vertebral column Divided by the diaphragm into Thoracic cavity - heart and lungs Pericardial cavity : around the heart Pleural cavity: around the lungs Abdominopelvic cavity - most organs Peritoneal cavity - coelomic space Epithelial Tissue An epidermal membrane, or epithelium, covers every surface of the vertebrate body Can come from any of the 3 germ layers Cells of epithelia are tightly bound together Provide a protective barrier Epithelias possess remarkable regenerative powers replacing cells throughout life Epithelial tissues attach to underlying connective tissues by a fibrous membrane Basal Surface - secured side Apical surface - free side Inherent polarity important for their function Two General classes Simple - one layer thick Stratified - several layers thick Each class subdivided into Squamous cells - flat Cuboidal cells - about as wide as tall Columnar cells - taller than they are wide Simple Epithelium Simple squamous epithelium Lines blood and lungs capillary Delicate nature permits diffusion Simple cuboidal Lines kidney tubules and several glands Simple columnar epithelium Lines airways of repiratory tract and most of the gastrointestinal tract Connective Tissues Derive from embryonic mesoderm Divided into two major classes Connective tissue proper Loose or dense Special Connective Tissue Cartilage, bone, and blood All have abundant extracellular material called the matrix Protein fibers plus ground substance Connective tissue Proper Fibroblasts produce and secrete extracellular matrix Loose connective tissue Cells scattered within a matrix that contains a large amount of ground substance Strengthened by protein fibers Collagen - supports tissue Elastin - makes tissue elastic Reticulin - helps support the network of collagen Nerve Tissue Cells Include neurons and their supporting cells (Neuroglia) Most Neurons consist of three parts Cell body - contains the nucleus Dendrites - highly branched extentions Conduct electrical impulses toward the cell body Axon - Single cytoplasmic extension Conducts impulses away from cell body Neuroglia Do not conduct electrical impulses Support and insulate neurons and eliminate foreign materials in and around neurons Associate with axon to form an insulating cover called the myelin sheath Gaps (Nodes of Ranvier) are involved in acceleration of impulses Nervous system is divided into Central Nervous system (CNS) Brain and spinal cord Integration and interpretation of input Peripheral nervous system (PNS) Nerves and ganglia (Collection of cell bodies) Communication of signal to and from the CNS to rest of body Overview of Organ Systems Communication and integration Three organ systems detect external stimuli and coordinate the body’s responses Nervous, sensory, and endocrine systems Support and movement Musculoskeletal system consists of two interrelated organ systems Regulation and maintenance Four organ systems regulate and maintain the body’s chemistry Digestive, circulatory, respiratory, and urinary systems Defense The body regulates itself Integumentary and immune systems Reproduction and development The biological continuity of vertebrates In females, the system also nurtures the developing embryo and fetus Reply Link to post Share on other sites More sharing options...
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