Animal Cell Exam 3

plasma membrane separates

intracellular fluid from extracellular fluid

plasma membrane controls

passage of solutes into and out of the cell

determines whether a solute can cross the membrane

chemistry of the solute and membrane

plasma membrane is made of

proteins and lipids

plasma membrane is a

phospholipid bilayer

phosphate head

hydrophilic

phosphate tail

hyrophobic

phospates have

nitrogen containing group, phosphate group, glycerol, fatty acid tails

saturated fatty acid tails can

pack together tightly making wall stiffer

unsaturated fatty acid tails

double bonds of carbon, can not pack tightly

phospholipid subtypes

make up majority of membrane lipids

glycolipids

protects cells, prevent cell fusion

glycolipids have

short carbohydrate chains on ECF face

cholestreol

reduces membrane fluidity by holding phospholipids still

flippase

flips heads into inside cell

floppase

flips heads into outside cell

scramblease

can put heads to inside and outside of cell

lipid rafts

lipids that gather into rigid patches, can stiffen or create more movement

lipid raft functions

cell signaling;close assembly of effectors, forming caveolae, cytoskeleton anchoring

integral protein

penetrate membrane

transmembrane proteins

pass through plasma pmembrane

hydrophilic regions

contact intracellular fluid and extracellular fluid

hydrophobic regions

pass through plasma membrane

peripheral

do not penetrate membrane, are usually anchored

membrane protein receptors

bind chemical signals

second messenger systems

communicate within cell (relay messages)

enzymes

cell metabolism reactions, addition of chemical groups

channel protein

open or gated

carriers

bind solutes and transfer them across membrane

cell identify markers

glycoproteins act as unique “tag”

cell adhesion molecules

mechanically link cell to another cell or to extracellular material

passive transport

no cellular energy required, solutes go down (with) gradient

active transport

cellular transport is required, solutes go against gradient

passive mechanisms

simple diffusion, osmosis, facilitated diffusion

active mechanisms

vesicular transport, primary active transport (vesicular transport require ATP), secondary active transport (does bot require ATP)

Molecules with nonpolar covalent bonds are

typically hydrophobic

molecules with polar covalent bonds are

typically hydrophilic

transport proteins

channel proteins, gated ion channels, carrier proteins

channel proteins transport solutes via

facilitated diffusion and have specificity

ion movement strongly influences

water movement

osmosis

a specialized form of facilitated diffusion

types of ion channels

voltage gated, chemically gated, mechanically gated

gated ion channels

are quite a stimulus to transport solutes via facilitated diffusion and have specificity

chemically gated

chemical messenger binds to protein and induces opening

when acetylcholine neurotransmitters bind to receptor

it permits passage of Na+ and K+ ions

mechanically gated

mechanical force on cell membrane physically opens channel

carrier proteins transport solutes via

facilitated diffusion or active transport and have specificity

types of active transport proteins

coupled transporters and ATP-driven pumps