bio 110 exam 2- chp. 4, 5, 6, 7, and 8.1

cytoplasm

includes everything in the plasma membrane

cytosol

region of the eukaryotic cell that is outside the cell organelles but inside the plasma membrane

endomembrane system

network of membranes

nuclear envelope

double-membrane structure enclosing the nucleus

chromosomes

composed of DNA and proteins

nucleolus

ribosome synthesis occurs in the _________

is a region of nucleus where ribosomes are synthesized

endoplasmic reticulum

network of folded membrane that form flattened, fluid-filled tubules

rough ER

studded with ribosomes

protein synthesis

Rough ER is involved in _________ and sorting

smooth ER

lacks ribosomes

phospholipids and steroids

Smooth ER is involved in synthesis of ________ and ________.

golgi apparartus

stack of flattened, membrane-bound compartmenta

vesicles

_______ transport materials between stacks

protein processing, protein sorting, some protein folding, and protein secretion

Golgi apparatus functions:

lysosomes

perform intercellular digestion of macromolecules

acid hydrolases

hydrolysis

lysosomes contain digestive enzymes called _____________ that perform ______.

autophagy

recycling of worn-out organelles through endocytosis

central vacuoles

vacuoles in plants for storage and support

contractile vacuoles

vacuoles for expelling excess water

phagocytic vacuoles

vacuoles for processing food

peroxisomes

catalyze certain reactions that break down molecules by removing hydrogen or adding oxygen

also originate from the ER via vesicles

mitochondria and chloroplasts

semiautonomous organelles

reproduce

semiautonomous organelles grow and divide to _______ themselves

make ATP

Mitochondria's primary role is to _________.

photosynthesis

________ occurs in the chloroplast.

Photosynthesis

capture light energy to synthesis glucose

microtubules, intermediate filaments, and actin filaments

cytoskeleton is made of 3 types of protein filaments:

microtubules

long, hollow structures made of tublin

intermediate filaments

rope-like structure; ex. keratin

actin filaments

two actin chains in a spiral; also known as microfilaments

phospholipid bilayer

framework of the membrane

amphipathic

phospholipids are _______ molecules

lipid, protein, carbohydrate

membrane is considered a mosaic of ______, _______ and _______ molecules.

transmembrane proteins

physically embedded in hydrophobic portion of the bilayer

lipid-anchored proteins

amino acid of the protein is covalently attached to a lipid

peripheral membrane proteins

noncovalently bound either to integral membrane proteins or to polar head groups of phospholipids

fluidity

ability of individual molecules to flow within a membrane

semifluid

membranes are _______.

ATP

flippase requires _____ to transport lipids between leaflets

cholesterol

_______ controls fluidity in membranes.

lipid raft

a group of lipids that floats together as a unit within the larger sea of lipids in the membrane

length, presence of double bonds, presence of cholesterol

factors affecting fluidity

cytosol and membrane

phospholipids are half made in _______ and ______.

glycolipid

carbohydrate attached to a lipid

glycoprotein

carbohydrate attached to a protein

N-linked glycosylation

carbohydrate attached to a nitrogen atom

O-linked glycosylation

addition of sugars to oxygen atom

selectively

the plasma membrane is ________ permeable.

passive transport

transport: requires no energy; moved down concentration gradient

simple diffusion

transport: diffusion of a solute from higher to lower concentration without transport protein

facilitated diffusion

diffusion of a solute with aid of transport protein from high to lower concentration

active transport

transport: requires ATP; lower to higher concentration

CO2, N2, O2

high permeability

Water and urea

moderate permeability

sugars

low permeability

amino acids, ATP, proteins, polyssaccharides, nucleic acids

very low permeability

osmosis

water diffuses through amembrane with more water to less water

osmotic pressure

tendency for water to move into any cell

isotonic

equal water and solute concentration

hypertonic

high solute concentration (more water outside cell)

hypotonic

low solute concentration (more water inside cell)

crenation

shrinkage of a cell in hypertonic solution

osmotic lysis

swelling and bursting of a cell in a hypotonic solution

turgor pressure

pushes plasma membrane against cell wall

plasmolysis

plants wilting because water leaves plant cells

transport proteins

transmembrane protein that provides a passageway

channels and transporters

two classes of transport proteins:

channels

_____ form an open passageway for the direct diffusion of ions or molecules across the membrane.

transporters

carriers, or pumps

uniporter

transports single molecules

symporter

transports two or more molecules in same direction

antiporter

transports two or more molecules in opposite directions

primary active transport

active transport that directly used energy from ATP

secondary active transport

active transport that uses pre-existing gradient to drive transport

exocytosis

substances excreted into cells

endocytosis

brings substances into cells

receptor-mediated, pinocytosis, phagocytosis

three types of endocytosis

receptor-mediated endocytosis

involves cargo binding to specific receptors

pinocytosis

"cell-drinking"

phagocytosis

"cell-eating"

kinetic energy

associated with movement

potential energy

due to structure or location

chemical energy

energy in molecular bonds; form of potential energy

energy cannot be created or destroyed

first law of thermodynamics

transfer of energy from one form to another increases the entropy

second law of thermodynamics

exergonic

spontaneous; negative free energy change

endergonic

not spontaneous; positive free energy change

catalyst

an agent that speeds up the rate of a chemical reaction

enzymes

protein catalysts in living cells

ribosomes

RNA molecules with catalytic properties

activation energy

initial energy to start a reaction

active site

location where reaction takes place

substrates

reactants that bind to active site

enzyme-substrate complex

formed when enzyme and substrate bind

affinity

the degree of attraction between an enzyme and its substrate

high

ATP and glucose have _______ affinity.

low

ADP and glucose have ________ affinity.

Vmax

maximal rate

Km

half maximal value

competitive inhibition

Km increases, Vmax stays the same