Anatomy exam ch 3

plasma membrane

forms the cells outer boundary and separates the cells internal environment from the outside environment

cytoplasm

contains all the cellular contents between the plasma membrane and the nucleus

nucleus

large organelle that contains DNA in molecules called chromosomes

ion channel

forms a pore which a specific ion can flow to get across the membrane

carrier protein

transports a specific substance across the membrane by undergoing a change in shape

receptor protein

recognizes specific ligand and alters cell's function in some way

enzyme

catalyzes reaction inside or outside cell

linker protein

anchors filaments inside and outside plasma membrane

glycoprotein

distinguishes cells

simple diffusion

substances move freely through the lipid bilayer

facilitated diffusion

integral protein assists a specific substance

channel-mediated facilitated diffusion

integral protein assists a specific substance

primary active transport

energy derived from hydrolysis of ATP pumps a substance

secondary active transport

energy stored in ion gradient is used to drive other substances across the membrane against their own gradients

phagocytosis

"cell eating"

filaments in cytosol

microfilaments, intermediate filaments, microtubules

microfilaments

generate movement and provide mechanical support

intermediate filaments

stabilize the position of organelles

microtubules

help determine cell shape

concentration gradient

the difference in the concentration of a chemical between one side of the plasma membrane and the other

electrical gradient

the difference in concentration of ions between one side of the plasma membrane and the other

factors that influence diffusion

steepness of the concentration gradient, temperature, mass of diffusion substance, surface area, diffusion distance

hypotonic solution

red blood cell undergoes hemolysis

hypertonic solution

red blood cell undergoes crenation

active transport: secondary

energy stored (in a hydrogen or sodium concentration gradient) is used to drive other substances against their own concentration gradient

active transport: primary

energy derived from ATP changes the shape of a transporter protein which pumps a substance across a plasma membrane against its concentration gradient

endocytosis

materials move into a cell in a vesicle formed from the plasma membrane

exocytosis

membrane-enclosed secretory vesicles fuse with the plasma membrane and release their contents into the extracellular fluid

transcytosis

a combination of endocytosis and exocytosis used to move substances from one side of a cell, across it, and out the other side

cytosol

the intracellular fluid portion of the cytoplasm

organelles

specialized structures that have specific shapes and perform specific functions

cytoskeleton

network of protein filaments throughout the cytosol that provide structural support for the cell

cilia

short, hair-like projections from the cell surface, move fluids along a cell surface

flagella

longer than cilia, move an entire cell

endoplasmic reticulum

network of membranes in the shape of flattened sacs or tubules

golgi complex

consists of 3-20 flattened, membranous sacs called cristernae; modify, sort, and package proteins for transport to different destinations