Chapter 2 Cell Physiology Flashcards
Plasma membrane
a thin membranous structure that encloses each cell and is composed mostly of lipid (fat) molecules and studded with proteins.
Cell theory
The cell is the smallest structural and functional unit capable of carrying out life processes; the functional activities of each cell depend on the specific structural properties of the cell; cells are the living building blocks of all multicellular organisms; an organism’s structure and function ultimately depend on the collective structural characteristics and functional capabilities of its cells; all new cells and new life arise only from preexisiting cells; because of this continuity of life, the cells of all organisms are fundamentally similiar in structure and function
nucleus
typically the largest single organized cell component, can be seen as a distinct spherical or oval structure, usually located near the center of the cell.
nuclear envelope
a double-layered membrane which separates the nucleus from the rest of the cell.
ribonucleic acid (RNA)
plays a role in protein synthesis
mRNA
messenger RNA which exits the nucleus through the nuclear pores. within the cytoplasm, mRNA delivers the coded message to ribsomes, which “read” the code and translate it into the appropriate amino acid sequence for the designated protein being synthesized.
cytoplasm
portion of the cell interior not occupied by the nucleus. contains a number of discrete, specialized organelles and the cytoskeleton folding of proteins that serve as the cell’s “bone and muscle” dispersed within the cytosol.
Organelles
distinct, highly organized structures that perform specialized functions iwthin the cell.
cytoskeleton
an interconnected system of protein fibers and tubes that extends throughout the cytosol. gives the cell its shape, provides for its internal organization, and regulates its various movements.
endoplasmic reticulum
an elaborate fluid-filled membranous system distributed extensively throughout the cytosol. primarily a protein- and lipid-producing facotry.
rough er
consists of stacks of relatively flattened interconnected sacs
smooth er
a meshwork of tiny interconnected tubules
ribosomes
the workbenches where protein synthesis takes place.
vesicle
a fluid-filled, membrane-enclosed intracellular cargo container. Transport vesicles move to the golgi complex
golgi complex
closely associated with the ER. each golgi complex consists of a stack of flattened, slightly curved, membrane-enclosed saces. the sacs within each golgi stack do not come into physical contact with one another.
