BIO 101 Chapter 4

all cells capture and use_______

energy

kinetic energy

the energy of movement/motion

potential energy

stored energy that is available to do work

chemical bonds are_______

potential energy

if a cell cannot capture energy as it releases, it will be lost as______

heat

first law of thermodynamics

energy is never created or destroyed

heat energy is______

disordered

second law of thermodynamics

the entropy of the universe is increasing

entropy

the measure of disorder

entropy________as you go up the organizational chart

increases

metabolism

all chemical reactions in a cell

building molecules

requires energy

breaking down molecules

releases energy

anabolism

builds, requires energy

catabolism

breaks down, releases energy

endergonic reaction

forms bonds, requires energy

exergonic reaction

breaks bonds, releases energy

photosynthesis

endergonic reaction

cellular respiration

exergonic reaction

oxidation

loss of electrons, release energy

reduction

gain of electrons, gains energy, requires energy

electron transport chain

series of membrane proteins participating in sequential, linked, oxidation-reduction reactions

donor (in the ETC)

what is being oxidized

acceptor (in the ETC)

what is being reduced

ATP

adenosine triphosphate, cellular energy currency

ADP

adenosine diphosphate, reduced form of ATP

other energy carriers

NADPH, NADH, FADH2

ATP releases_______ by _______

stored energy; by removing innermost phosphate group by hydrolysis

ATP is formed during_____

cellular respiration

ATP hydrolysis is coupled with (fuels)

endergonic reactions

ATP synthesis is coupled with

exergonic reactions

ATP synthesis

producing ATP from ADP

ATP hydrolysis

breaking down ATP into ADP

energy

the ability to do work

enzyme

type of protein that speeds up chemical reactions

substrate

what an enzyme acts on

active site

where chemical reaction occurs on an enzyme

enzymes alter______to form______

substances; products

enzymes either______or______substrates

break; combine

enzymes lower______

activation energy

activation energy

the energy required to start a reaction

cofactors

non-protein helpers, catalyze reactions (commonly metal ions and vitamins)

inhibitors

prevent reactions

competitive inhibitor

blocks active site

non-competitive inhibitor

does not bond to active site, instead changes active site shape

inhibitor is often_____

the product of enzyme reactions

negative feedback

when the product of a reaction slows the production of more product (ex. homeostasis)

positive feedback

when the product of a reaction stimulates its own production (ex. blood clots)

what affects enzyme activity?

temperature, chemical factors (salt and pH)

the cell membrane regulates_____

homeostasis

what 2 factors determine how substances enter and exit?

concentration gradient and chemical nature of substance

gradient

difference in concentration between neighboring regions

concentration gradients dissipate______

without energy input

passive transport

does not require energy

goes down the gradient

includes simple diffusion, osmosis, and facilitated diffusion

active transport

requires energy

goes against the gradient

includes the sodium potassium pump, endocytosis, and exocytosis

maintaining a gradient_____

requires energy

simple diffusion

small, nonpolar molecules pass through the membrane

osmosis

the diffusion of water across a selectively permeable membrane (water follows solute)

isotonic

same (concentration of water is equal in and out of the cell)

hypotonic

swell (concentration of water is higher in the cell, water comes in)

hypertonic

shrink (concentration of water is high outside of the cell, water goes out)

facilitated diffusion

membrane proteins (helpers) transport substances across a cell membrane (polar and ions)

sodium potassium pump

Na+ and K+ ions are moved across the membrane in neuron and muscle cells

endocytosis

vesicles bring large substances into the cell

exocytosis

vesicles bring large substances out of the cell

calorie

the amount of energy needed to increase water’s temperature by a degree Celsius

pinocytosis

taking in of liquids

phagocytosis

taking in of solids