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Chapter 4 Anat/phy
Chapter 4 Anatomy & Physiology Vet Tech
Question | Answer |
---|---|
What are the four primary types of tissue | Epithelial, Connective, Muscle and Nervous |
What is Histology | Histology is the study of the microscopic structures of tissues and organs |
List seven functions performed by epithelial cells | 1 protect, cover and line other tissues 2. filter biochemical substances 3. absorb nutrients 4. provide sensory input 5. manufacture secretions 6. manufacture excretions 7. act as an interface layer that separates and defines the beginning and ending of d |
what four attributes characterize epithelial tissue in general | 1. epithelial cells are polar 2. epithelial cells have lateral surfaces that are connected to neighboring cells by junctional complexes. 3. all epithelial cells lack blood vessels or capillaries 4. Most are innervated and provide valuable sensory input |
List four types of cellular junctions | 1 Tight Junction 2. Desmosome 3. Hemidesmosome 4. Gap Junction |
Describe the cellular junction - "Tight Junction" | formed by the fusion of the outermost layers of the plasma membranes of adjoining cells. Tight junctions are found in tissues where there can be no leaks - ie urinary bladder, the digestive tract |
Describe the cellular junction - "Desmosome" | strong, welded plaque that connects the plasma membranes of adjacent cells. the bond is mechanical coupling formed by filaments that interlock with one another just like the plastic fibers do in velcro. skin, heart and uterus are common desmosome tissues |
Describe the cellular junction -"Hemidesmosome" | juntions that look like half-desmosomes and link epithelial cells to the basement membrane |
Describe the cellular junction - "Gap Junction" | made of tubular channel proteins called connexons and extend from the cytoplasm of one cell to the cytoplasm of another. Found in cardiac and smooth muscle cells, where they help coordinate contraction |
Why do some epithelial cells have cilia and microvilli. What role do they play and where are they found in the body | Microvilli increase the surface area of cells and allow more absorption and secretion. They are found on epithelial cells in the intestines and urinary tract. Cilia are found on the free surfaces of cells , usually in the respiratory and urogenital trac |
what are the three types of muscle | skeletal, smooth and cardiac |
Describe skeletal muscle | skeletal muschle cells are striated, or striped, because they have alternating bands of light and dark. it is usually controlled through conscious effort and is therefore called voluntary muscle. |
describe smooth muscle | smooth muscle is composed of small, spindle-shaped cells that lack striations or bands and appear smooth. The contractions cannot be consciously controlled. Smooth muscle is a non-striated involuntary muscle. |
describe cardiac muscle | exists only in the heart and possesses the remarkable ability to contract even when neural input has been altered. Cardiac muscle is striated involuntary muscle. |