Intro To Micro Flashcards
Tissue
Aggregation of related cells, together with their specific extracellular matrix
Domains of cell
The organelles of the cell
Extracellular matrix
Consist of proteins and other large molecules secreted by cells bathed in extracellular fluid
Epithelium
Cells are close together and form a barrier lining the free surfaces of the body
Connective tissue
Abundant ECM with scattered cells. Important for support. May be loose or dense includes cartilage and bone
Contractile tissue
Cells have proteins (actin and myosin) arranged for and generation of force. Skeletal, cardiac and smooth muscle
Nervous tissue
Densely packed cells. Have specializations for electrical communication
Membranes
Help establish compartments and domains. Cell plasma membrane separates the cytosol from the extracellular space
Fluid mosaic model
Encompasses lipid and protein elements of membranes. Phospholipids are amphipathic with non polar tails and polar heads. Cholesterol modulates fluidity
Phospholipid bilayer
Permeable to water and small uncharged molecules but impermeable to other molecules.
Integral membrane proteins
Require detergent solubilization techniques to separate the proteins from the membrane. Many contain one or more sequences of hydrophobic amino acids to insert through the bilayer
Peripheral membrane proteins
Loosely associated with the bilayer and can be isolated with mild detergent. Potentially may diffuse laterally within the plane of the membrane
Glycoconjugates
Sugars associated with protein in the membrane. They are involved in cell to cell interactions including cell-cell recognition and cell-matrix interactions. Almost exclusively on the non-cytosol side of membrane. At external plasma membrane they help to maintain a net negative charge, which helps positively charged water stay at the cell surface
Polarity
Asymmetrical internal organization
Apical surface
Toward the free surface
