AP Bio Unit 2

prokaryotes

first cell walls were prokaryotic

cell walls are complex carbons

lack internal bound membranes

typically have circular bond membranes

cell membrane

controls the exchange with the cells external environment

allows the cells to maintain an internal

critical for homeostasis

mostly composed of phospholipids

phospholipids

polar/hydrophillic heads

non-polar/hydrophobic tails

embedded

proteins are ____ in the membrane

fluid mosaic model

describes the structure of the plasma membrane as a mosaic of phospholipids, cholesterol, and proteins that give the membrane a fluid character

intercellular joinings

allows cells to connect with one-another

enzymes

catalyze reactions

signaling transduction

proteins that act as receptors for signaling membranes

structure of membrane proteins

membrane proteins must be able to interact with the membrane, since the R-group of amino acids define their properties

membrane

non-polar amino acids interact with each other within the inner ____

membrane

polar amino acids interact with each other in the outer ____

carbohydrates stick out the membrane

cells recognize other cells by binding to molecules often containing carbs on the extracellular Surface of the cell membrane. carbohydrates are usually short, branched chains of fewer than 15 sugar units

glycoproteins

carbohydrates attached to a protein

glycolipid

carbohydrates attached to a lipid

fluidity

animal cells maintain ____ with cholesterol

cholesterol

prevents phospholipids from packing to close in the cold weather

holds monolipids together

Simple diffusion

type of transport where particles must be small and unchanged

no proteins used

facilitated diffusion

transport are large and charged

protein is used

osmosis

diffusion across a selectively permeable membrane

facilitated by aquaporins

hypotonic

solution has higher concentration

isotonic

solution has equal concentration to the cell

hypertonic

solution has lower concentration than the cell

exocytosis

cell secretes molecules by the fusion of vesicles with the plasma membrane

endocytosis

cell takes in molecules by forming new vesicles found in the membrane

Phagocytosis

type of endocytosis with cellular “eating”

pinocytosis

endocytosis with cellular “drinking”

receptor

mediated endocytosis

cytoplasm

area outside the cell filled with liquid

houses organelles and dissolves other substances

contains enzymes for reactions

ribsome

small structure made of RNA and proteins

makes proteins based on instructions from the nucleus

nucleolus

small dense region in the nucleus that makes ribosomes

chromatin

DNA around proteins

allows DNA to be packed tightly

Smooth ER

internal membrane system that “looks smooth”

makes lipids and detoxes the cell

Rough ER

protein production happens here, also exports proteins out of the cell

golgi apparatus

protein modification and transport

chloroplasts

where photosynthesis occurs

thylakoids are interconnected w this

granum

stack of chloroplasts

stroma

fluid outside of granumn

cell division

Nucleus, chromosomes, centrioles, mictrotubes, microfilaments

endosymbiont theory

mitochondria and chloroplasts display similarities to bacteria

cristae

infoldings of the inner membrane

mitochondrial matrix

enclosed by inner membrane, contains different enzymes, DNA, and lysosomes

cytoskeleton

network of protein fibers being sent through the cytoplasm

motor proteins

the cell depends on interaction between this and the cytoskeleton to survive

cila

projection that extends from some cells

intergal proteins

penetrate the hydrophobic inner layer

peripheral proteins

embedded to the surface

aquaporins

channel proteins

turgid

very firm

flaccid

limp

sodium-potassium pump

exchanges NA for K

electrogenic pump

transport that engorges voltage across the membrane

lysosomes

membrane-bound organelle in eukaryotic cells that contains digestive enzymes, functioning as the cell's waste disposal and recycling center

cytosol

the aqueous component of the cytoplasm of a cell, within which various organelles and particles are suspended.

low

low temp ——> ____ fluidity

high

high temp ——> ____ cholestrol

hydrophilic head

contains negatively charged phosphate group

faces outward, contacting the aqueous fluid both inside and outside the cell.

readily forms electrostatic interactions with the phospholipid heads.

hydrophobic tail

fatty acid

in interior of membrane

saturated fatty acid

NO double bonds

doesn’t result in kink

easily

selective permeability

nonpolar gases can _____ pass the lipid region of the membrane due to ___________

extracellular matrix

non-cellular network of proteins and polysaccharides that surrounds and supports cells in tissues and organs

collagen

plays a key role in giving tissues strength and structural integrity