Chapter 32 Flashcards
Endocrine System
Coordinates body activities (such as digestion and metabolism). Releases signaling molecules (hormones) into the bloodstream.
Endocrine Glands
Ductless organs made up of endocrine cells. Produce hormones.
Epithelial Tissue
Sheets of closely packed cells. Covers the outside of the body and lines the organs and cavities. Functions as barriers against injury, pathogens and fluid loss.
Nervous Tissue
Functions in the receipt, processing and transmission of information. Neurons are the basic units. Also contain support cells called glia which help nourish, insulate and replenish neurons.
Muscle Tissue
Three types: skeletal, cardiac and smooth. Muscle cells consist of filaments containing proteins actin and myosin enabling muscles to contract.
Connective Tissue
Consists of cells scattered through an extracellular matrix. Include loose CT which holds skin and other organs in place, fibrous CT found in tendons and ligaments, adipose tissue which stores fat, blood, cartilage and bone.
Interstitial Fluid
Fluid between capillaries and tissues through which oxygen hormones and other substances is transported.
Negative Feedback
A control circuit or loop that reduces, “damps”, the stimulus. Turns off the endocrine pathway.
Positive Feedback
A control mechanism in which the response reinforces the stimulus, leading to an even greater response. Helps drive processes to completion.
Homestasis
Maintenance of internal balance. By which animals achieve a relatively constant internal environment.
Radiation
The emission of electromagnetic waves by all objects.
Evaporation
Removal of heat from the surface of a liquid that is losing some of its molecules as gas. Helps cool animals.
Convection
Transfer of heat by the movement of air or liquid past a surface.
Conduction
Transfer of heat between molecules of objects in contact with each other.
Urea
A nitrogenous waste excreted by animals. The product of an energy-consuming metabolic cycle that combines ammonia with carbon dioxide in the liver.
