Transcript Tissues
Multicellular life Evolution of multicellular life Animal tissue types Campbell Fig1.1 Campbell Fig 20.2 Animal tissue types • What is a tissue? • A cooperative unit of many very similar cells that perform a specific function. • Examples – – – – Epithelial Connective Muscle Nervous Epithelial tissue • Covers and lines the body and its parts • One surface free, the other bound to basement membrane • Tissues are named by – Shape of cells – Number of layers of cells Epithelial tissue Campbell Fig 20.4 • • • • • Simple = single layer Stratified = multiple layers Squamous = flat (tiles) Cuboidal = like dice Columnar = like bricks Simple Squamous Simple Cuboidal In the kidney tubules Campbell Fig 20.4 Lines the lungs Stratified Squamous Epithelium Campbell Fig 20.4 Lines the esophagus Ciliated columnar epithelium Campbell Fig 20.4 Lines the air ways in the respiratory system Connective tissue • Binds other tissues an provides support matrices • Few cells in a nonliving matrix • Three fiber types – Collagen fibers – Elastic fibers – Reticular fibers • Fibroblasts - cells that produce connective tissue Loose connective tissue (Areolar) Campbell Fig 20.5A Holds other tissue in place A “binding” material Other Connective tissues Campbell Fig 20.5 Loose Fibrous connective Adipose Cartilage Blood Bone Tendons Dense connective tissue that Attaches muscle to bone Like Campbell Fig 30.7 Bone Tissue • Osteocytes • Haversian canal • Lamelle (matrix) Campbell Fig 20.5D Bone Development Muscle tissue • Functions in movement • Bundles of long cells ( muscle fiber= muscle cell) • Skeletal muscle – Attached to bones by tendons, produces voluntary movement – Striated unbranched • Smooth muscle – Found in walls of digestive tract, produces involuntary movements – Unstriated, spindle shaped • Cardiac Muscle – Striated , branched, produces heartbeat Muscle tissue Campbell 20.6 Cardiac muscle Skeletal muscle Smooth muscle Nervous Tissue • Responsible for coordinating body activties • Neurons are nerve cells • Motor neurons are nerves that activate muscles • Sensory neurons transmit information • Composed of cell body and dendrites • Supported by glial cells Campbell Fig 28.3A Modified Nervous Tissue Campbell Fig 28.2 Summary