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Tanique Jones
Physiology weeks 1-6 set 1
what are the basic copmponents of a control system? | 1. Sensor mechanism 2. Integrator or control center 3. Effector mechanism 4. Feedback |
what is negative feed back | Negative feedback produces an action that is opposite to the change that activated the system. |
Positive feedback vs negative feedback | Positive feedback control systems are stimulatory. Instead of opposing a change in the internal environment and causing a return to normal, positive feedback tends to amplify or rein-force the change that is occurring |
Levels of homeostatic control | intracellular control: operates at cellular level Intrinsic control: mechanisms operate at the tissue and organ levels Extrinsic control means “outside” control and operates at the system and organism levels. |
Homeostasis | constancy of the body’s in-ternal fluid environment. It is regulated by a complex network of mechanisms that include feedback loops |
Epithelial tissue | One or more cell layers with little extracellular matrix. May form either sheets or glands Covers and protects the body surface Lines body cavities Transport of substances (absorption, secretion, excretion) Glandular activity |
Connective tissues | Sparsely arranged cells, large amount of extracellular matrix containing structural fibers (and sometimes mineral crystals Supports body structures Transports substances throughout the body |
Muscle tissue | Long fiber like cells sometimes held together by extracellular fibers Produces body movements, heat, and movements of organs |
Nervous tissue | Mixture of many cell types, including several types of neurons (conducting cells) and neuroglia (support cells) communication between body parts and regulation of functions |
contractile unit of a muscle | Sarcomere |
according to the sliding filament theory | actin moves past myosin |
symphasis | joints bound by fibrocartilage |
synchrondrosis | a cartilaginous joint where bones are joined together by hyaline cartilage, or where bone is united to hyaline cartilage |
muscle length remains the same but muscle tension increases | isometric contraction |
energy required for muscular contraction is obtained by hydrolysis of | atp |