What is a TISSUE? A group of cells, usually similar, which share a particular function. Each organ is made up of tissues. What happens during the process of cell differentiation? Each cell develops a characteristic set of structural features, and each cell has to contribute one piece toward the overall function of the organism, so that all the vital functions can be covered. During differentiation, cells in nearby locations become able to work together. After differentiation, cells do not change their function throughout their life cycle. What does the presence of large numbers of microvilli on the exposed surfaces of epithelial cells indicate? That this is the area where absorption and secretion take place. These cells are transportation specialists. They are probably located along portions of the digestive and urinary tracts. What are the two types of tissues? Epithelium Connective Tissue What are the two categories of connective tissue? Fibrous (proper) connective tissue Special connective tissue What are the 5 types of Proper connective tissue? Adipose Reticular Loose Dense regular Dense irregular What are the 5 types of Special connective tissue? Cartilage Bone Blood Muscle Nerves What is a sheet of cells that separate one region from another? Epithelium What supplies oxygen and nutrients to the epithelium? Blood vessels in the connective tissue What are the two functions of epithelia? To separate one region from the other; e.g. skin, stomach lining, blood vessel lining, intestine, heart. The epithelial cells are the primary type of tissue that protects the underlying structures What sits on top of connective tissue and is connected to it by the basement membrane? Epithelia What is the basement membrane made of? The basement membrane is made of protein fibers What is the ONLY function of the basement membrane? To attach the epithelium to the connective tissue beneath it
What are the five types of proper (fibrous) connective tissue? Adipose connective tissue Reticular (lymph nodes) Loose connective tissue Dense Irregular connective tissue Dense Regular connective tissue What type of tissue has lots of adipocytes? What is stored inside? Adipose Tissue Fat is stored inside What tissue are lymph nodes? Reticular What is the least specialized connective tissue? Areolar What type of tissue’s main cell type is Fibroblast and is common in areas just deep to epithelium? Loose connective tissue (Areolar) How is areolar (loose) connective tissue formed? formed by the differentiation of embryonic connective tissue Skeletal muscle is bound together by what type of tissue? Areolar How is dense connective tissue formed? formed by the differentiation of embryonic connective tissue What are the main characteristics of Dense Irregular connective tissue? Has lots of collagen fibers Fibers have irregular position; no pattern Extremely strong in all directions Found in areas of body where strength is needed (joint capsules and deeper layer of dermis) What are the main characteristics of Dense Regular connective tissue and an example of where it can be found? Has lots of collagen fibers that have a pattern and run in same direction. Stronger than Irregular, but in one direction. Ligaments and tendons (they are not muscle tissue) What tissue type are tendons? Dense regular connective tissue (they are not muscle tissue!) What are five three types of special connective tissue? Cartilage Bone Blood Muscles Nervous tissue What is the main cell type of cartilage? Chondrocytes What type of tissues extracellular matrix is dense collagen, almost solid, very rigid, and avascular? Cartilage What are the three types of cartilage, and where is each one found? Which Hyaline Cartilage (joints; most common) Elastic Cartilage (ear)