AP Biology Unit 2

prokaryote

A unicellular organism that lacks a nucleus and membrane bound organelles

Eukaryote

A multicellular organism that contains a nucleus and membrane bound organelles

Nucleus

Control center of the cell, contains DNA

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production

ER

transports materials throughout the cell

Golgi apparatus

A system of membranes that modifies and packages proteins for export by the cell

Ribosomes

site of protein synthesis

Vacuole

stores water, food, and waste (bigger in plants)

Lysosomes

break down waste, contain digestive enzymes

Chloroplast

An organelle found in plant and algae cells where photosynthesis occurs - makes sugar

Cell Wall

A rigid layer that surrounds the cells of plants and some other organisms for protection and support

Cell Membrane

semipermeable - controls which substances can enter or leave the cell

phospholipid

a lipid that contains phosphorus and that is a structural component in cell membranes

channel protein

A membrane protein, specifically a transport protein, that has a hydrophilic channel that certain molecules or atomic ions use as a tunnel

carrier protein

Transport protein that changes shape when a particle binds with it

cholesterol

can decrease fluidity of the cell membrane

glycoprotein

A protein with one or more carbohydrates covalently attached to it.

glycolipid

a lipid with one or more covalently attached carbohydrates

aquaporin

A membrane protein that facilitates the passage of water

Surface Area to Volume Ratio

ratio that determines the efficiency of a cell

diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

osmosis

Diffusion of water through a selectively permeable membrane

facilitated diffusion

Movement of specific molecules across cell membranes through protein channels

passive transport

the movement of substances across a cell membrane without the use of energy by the cell

active transport

Energy-requiring process that moves material across a cell membrane against the concentration gradient

endocytosis

The process of taking liquids into a cell by engulfing them in a membrane.

exocytosis

release of substances out a cell by the fusion of a vesicle with the membrane.

osmoregulation

The control of water balance.

hypertonic

Having a higher concentration of solute than another solution (cell shrivels)

hypotonic

Having a lower concentration of solute than another solution (cell swells)

isotonic

when the concentration of two solutions is the same

plasmolysis

Collapse of a walled cell's cytoplasm due to a lack of water

turgor pressure

The pressure inside of a plant vacuole as it against the cell wall.

compartmentilization

Parts within parts which increase surface area and specialization

endosymbiotic theory

a theory that states that certain kinds of prokaryotes began living inside of larger cells and evolved into the organelles of modern-day eukaryotes