AP Bio Unit 2 Vocab

Prokaryotes

Cells that do not contain membrane bound organelles

Eukaryotes

Cells that contain membrane bound organelles such as a nucleus, mitochondria, etc.

Animal cell

Eukaryotic cell containing membrane-bound organelles without a cell wall or chloroplasts

Plant cell

Eukaryotic cell containing membrane-bound organelles in addition to a cell wall and chloroplasts

Bacteria cell

Type of prokaryotic cell that doesn't have membrane bound organelles, does not have a nucleus

Organelle

A tiny cell structure that carries out a specific function within the cell

Nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction

Cytoplasm/cytosol

Cell liquid in which chemical reactions occur. Holds and cushions the organelles.

Ribosome

Cytoplasmic organelles used to synthesize proteins

Rough ER

A network of interconnected membranous sacs in a eukaryotic cell's cytoplasm; covered with ribosomes that make membrane proteins and secretory proteins.

Smooth ER

Organelle that creates lipids

Golgi apparatus

Stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum

Lysosome

Cell organelle filled with enzymes needed to break down certain materials in the cell

Chloroplast

Organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy

Mitochondria

An organelle found in large numbers in eukaryotic cells in which the biochemical processes of respiration and energy production occur.

Cell membrane

The semipermeable membrane surrounding the cytoplasm of a cell that controls transport of materials

Cell wall

A rigid structure that surrounds the cell membrane and provides support to the cell in plant cells and prokaryotes

Vacuole

Cell organelle that stores materials such as water, salts, proteins, and carbohydrates

Flagellum

A long, hair like structure that grows out of a cell and enables the cell to move.

Plasmodesmata

Channels through cell walls that connect the cytoplasms of adjacent cells

Compartmentalization

Membrane-bound organelles allow different parts of the cell to perform different functions at the same time

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

Organelles that have their own DNA

Mitochondria and chloroplast

Phospholipid bilayer

Plasma membrane layers (around entire cell and certain organelles) composed of phospholipid molecules arranged with polar heads facing the outside and nonpolar tails facing the inside.

Hydrophilic head

Polar portion of the phospholipid that faces outward in the phospholipid bilayer

Hydrophobic tail

Nonpolar portion of the phospholipid that faces inward in the phospholipid bilayer

Integral proteins

Proteins that penetrate the hydrophobic interior of the lipid bilayer

Peripheral proteins

The proteins of a membrane that are not embedded in the lipid bilayer but instead are on the surface

Surface area to volume ratio

A variable that decreases as cells grow, so that it sets a limit to the size of cells.

Permeability

The state or quality of a material or membrane that causes it to allow liquids or gases to pass through it

Simple diffusion

Movement of a small nonpolar solute from an area of high concentration to an area of low concentration directly through the membrane

Facilitated diffusion

Movement of large, polar, or charged molecules across cell membranes through protein channels

Aquaporins

A transport protein in the plasma membrane of a plant or animal cell that specifically facilitates the diffusion of water across the membrane

Endocytosis

A process in which a cell engulfs extracellular material through an inward folding of its plasma membrane to create an vesicle on the inside of a cell

Exocytosis

a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane.

Pinocytosis

A type of endocytosis in which the cell ingests extracellular fluid and its dissolved solutes

Phagocytosis

A type of endocytosis in which a cell engulfs large particles or whole cells

Symport

A membrane transport process that carries two substances in the same direction across the membrane, one molecule is passively moved providing energy to actively move the other molecule

Antiport

A membrane transport process that carries two substances in the opposite direction across the membrane, one molecule is passively moved providing energy to actively move the other molecule

Concentration gradient

Difference in the concentration of a substance on either sides of a membrane

ATP

Main energy source that cells use for most of their work (adenosine triphosphate)

Solute

A substance that is dissolved in a solution

Water potential

The physical property predicting the direction in which water will flow, governed by solute concentration and applied pressure.

Osmolarity

Total concentration of all solute particles in a solution

Hypotonic

When comparing two solutions, the solution with the lesser concentration of solutes

Hypertonic

When comparing two solutions, the solution with the greater concentration of solutes

Isotonic

Having the same solute concentration as another solution.