chapter 8 - cellular structure and function Flashcards
cell
basic unit of all forms of life
cell theory
fundamental concept of biology that states that all living things are composed of cells; that cells are the basic units of structure and function in living things: and that new cells are produced from existing cells
prokaryote
unicellular organism that lacks a nucleus
eukaryote
organism whose cells contain a nucleus
nucleus (of cell)
in cells, structure that contains the cell’s genetic material in the form of DNA
organelles
specialized structure that performs importnat cellular functions within a eukaryotic cell
cytoplasm
fluid portion of the cell outside the nucleus
nuclear envekope
The nuclear envelope, also known as the nuclear membrane, is made up of two lipid bilayer membranes that in eukaryotic cells surround the nucleus, which encloses the genetic material. The nuclear envelope consists of two lipid bilayer membranes: an inner nuclear membrane and an outer nuclear membrane.
ribosome
cell organelle consisting of RNA and protein found throughout the cytoplasm in a cell; the site of protein synthesis
rough ER
The endoplasmic reticulum can either be smooth or rough, and in general its function is to produce proteins for the rest of the cell to function. The rough endoplasmic reticulum has on it ribosomes, which are small, round organelles whose function it is to make those proteins.
smooth er
Functions of the Smooth Endoplasmic Reticulum. The smooth ER is important in the synthesis of lipids, such as cholesterol and phospholipids, which form all the membranes of the organism. In addition it is important for the synthesis and secretion of steroid hormones from cholesterol and other lipid precursors.
golgi apparatus
organelle in cells that modifies, sorts, and packages protein and other materials from the endoplasmic reticulum for storage in the cell or release out of the cell
mitochondria
cell organelle that converts the shemical energy stored in food into compounds that are more convinient for the cellulose
chloroplast
organelle that converts the chemical energy stored in food into compartments that are more convinient for the cellulose
vacuole
cell organelle that stores materials such as water, salts, proteins, and carbon dioxides
lysosome
cell organelle that breaks down lipids, carbon, one protein into small molecules the can be used by the rest of the cell
centrioles
In cell biology a centriole is a cylindrical organelle composed mainly of a protein called tubulin. Centrioles are found in most eukaryotic cells, but are not present in conifers, flowering plants and …
cell membrane
the semipermeable membrane surrounding the cytoplasm of a cell.
cell wall
strong supporting layer around the cell membrane in some cells (plant cells)
cytoskeleton
network of protein filaments in a eukaryotic cell that gives the cell its shape and internal orginization conducts individual in movement
lipid bilayer
flexible double-layered sheet that makes up the cell membrane and forms a barrier between the cell and its surrondings
selectively permeable
property of biblogical membrances that allows some substances to pass across it while other cannot; also called semi-permeable membrane
diffusion
process by which particles tend to move from an area where they are more concentrated to an area where they are less concentrated
osmosis
diffusion of water through a selectively permeable membrane
