Cell structures

flagellum

a long, whiplike structure that helps a cell to move

phospholipid

a molecule that is a constituent of the bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail

mitochondrion

a membrane‐bound organelle found in most eukaryotic cells; site of cellular respiration

chloroplast

an organelle found in plant and algae cells where photosynthesis occurs

ribosome

cytoplasmic organelles where proteins are synthesized

Golgi body

a structure in a cell that receives proteins and other newly formed materials from the endoplasmic reticulum, packages them, and secretes them from the cell

endoplasmic reticulum

a system of membranes that is found in a cell's cytoplasm and that assists in the production, processing, and transport of proteins and in the production of lipids

cell wall

a rigid structure that surrounds the cell membrane and provides support to the cell; composed of cellulose in plants

nucleus

a large organelle that contains the cell's genetic material in the form of DNA and controls many of the cell's activities

nucleolus

a specialized structure in the nucleus; active in the synthesis of ribosomes

cholesterol

a lipid that forms an essential component of cell membranes by improving the fluidity of the membrane

glycoprotein

a protein with one or more carbohydrates covalently attached to it

matrix

innermost fluid of the mitochondrion

vesicle

small membrane-bound sac that functions in moving products into, out of, and within a cell

lysosome

an organelle containing digestive enzymes

granum

a stack of thylakoids in a chloroplast

stroma

the fluid of the chloroplast surrounding the thylakoid discs

thylakoid disc

a flattened membranous sac in a chloroplast

cristae

series of folds in the inner membranes of mitochondria; where cell respiration occurs

cilia

hairlike projections that extend from the plasma membrane and are used for locomotion

cytoskeleton

a network of fibers that holds the cell together, helps the cell to keep its shape, and aids in movement

vacuole

a sac inside a cell that acts as a storage area

cytosol

fluid portion of cytoplasm

microtubule

a hollow rod composed of proteins that makes up part of the cytoskeleton

chromatin

granular material visible within the nucleus; consists of DNA tightly coiled around proteins