AP Bio: Energetics

Metabolism

Metabolism

cellular respiration and photosynthesis, all chemical reactions which occur in a living thing

Thermodynamics

how energy moves through a system

Why are enzymes necessary?

reactions don't often occur fast enough to support life

Catabolic pathway

decomposition, something that has organization and breaks apart, releasing energy

Anabolic pathway

synthesis, something that doesn't have organization and combines, requiring energy

Dephosphorylation

taking a phosphate group off of a molecule

Potential Energy

energy because of location, could at any moment turn into KE

1st law of thermodynamics

energy can never be created or destroyed, only change forms or be transferred (KE or PE)

2nd law of thermodynamics

energy conversion results in energy loss in the form of heat, energy transformation increases the entropy of the universe

Entropy

increasing randomness, ex: diffusion, matter wants to spread out, living things don't organize, occurs spontaneously

Enthalpy

how much energy is in a system

Catabolic reactions occur ___.

spontaneously

Anabolic reactions ____ occur spontaneously.

do not

Energy coupling

Fueling endergonic reactions by use of exergonic reactions

What is an example of energy coupling?

ATP breaking down to fuel other reactions

Enzyme

type of protein which speeds up a specific metabolic reaction by lowering the energy barrier

Activation energy

the amount of energy needed to start a chemical reaction

Substrate

reactants in chemical reaction which bind to enzyme to get changed into products

Active site

location on enzyme where reaction takes place, where the substrates bind to

induced fit

enzyme claps down on reactants, and changes shape a bit to do so as the reaction takes place, because the products are different shapes than the reactants

Enzyme substrate complex

enzyme + substrate

Cofactors

nonprotein enzyme helpers which can be permanent or temporary Ex: minerals zinc iron, copper

Coenzymes

Organic cofactors, most are vitamins. Ex. Vitamin D, B

Enzyme inhibitors

molecules which can turn off enzymes

Competitive inhibition

will bond with enzyme but not react with it, to turn it off, called competitive because it competes for the active site with the reactant that is trying to bond to the enzyme

Noncompetitive (alosteric enzyme)

does the same thing but doesn't bond to the active site, bonds to a different site (alosteric site), and turns it off by changing the shape of the enzyme

Feedback inhibition

when the product of a metabolic pathway accumulates and turns that pathway off

Bioenergetics

the study of how energy flows through living organisms

Spontaneous process

if a given process leads to an increase in entropy it can process without an input of energy, doesn't have to occur quickly, but instead it is energetically favorable

Free energy

the portion of a system's energy that can perform work when temperature and pressure are uniform throughout the system (ex: living cell)

As a reaction proceeds toward equilibrium, the free energy of the mixture of reactants and products what?

decreases

When can a process be spontaneous and perform work?

when it is moving toward equilibrium

Exergonic reaction

proceeds with a net release of free energy because the chemical mixture loses free energy G decreases negative delta G

Endergonic reaction

one that absorbs free energy from its surroundings because essentially stores free energy in molecules, G increases, positive delta G

What are the three main kinds of work that a cell completes?

chemical, transport, mechanical

How can the bonds between the phosphate groups of ATP be broken down?

through hydrolysis

What does hydrolysis involve in the breakdown of ATP?

Water being added to the last phosphate, which breaks it off and releases energy

How is ATP recharged?

ATP is renewable, just add the phosphate back onto the used ADP, the free energy needed to phosphorylate the ADP comes from the exergonic reactions (catabolism)

ATP

contains sugar ribose with nitrogenous base adenine and a chain of three phosphate functional groups

Phosphorylation

the transfer of a phosphate group from ATP some other molecule such as the reactant

What do most enzyme names end in?

ase

3

How much ATP can NADH produce?

2

How much ATP can FADH2 produce?

intermembrane space

H+ ions accumulate where in the mitochondria?

inner membrane

oxidative phosphorylation occurs where in the mitochondria?

matrix

the krebs cycle occurs where in the mitochrondia?

lactate

In lactic acid fermentation, pyruvate is converted to what?

inner membrane

Where is ATP synthase located in the mitochondria?

bacteria, fungi, and plants

What organisms undergo alcohol fermentation?

Ethyl alcohol, CO2, & ATP

What chemicals are produced in alcohol fermentation?

redox-reaction

What reactions involve the partial or complete transfer of one or more electrons from one reactant on another?

electron transport chain

Involves Active Transport, makes NADH & FADH. H+ move thru protein channels & build concentration gradient.

oxidative phosphorylation

The energy released though a chain of redox reactions is used to synthesize ATP by what?

oxidative phosphorylation

What process includes the electon transport chain and chemiosmosis?

ATP synthase

What is a protein complex embedded in the inner membrane that makes ATP

fats, proteins, and carbohydrates

What can all be used by cellular respiration to make ATP?

two

in alcoholic fermentation, how much alcohol is formed with each molecule of glucose?

the citric acid cycle (Krebs)

The carbon dioxide that animal cells breathe out is created by what process?

Fermentation

After glycolysis, if no oxygen is present, what occurs?

Lactic Acid

Type of fermentation used to make yogurt, cheese, saurkraut, kimchi, buttermilk, etc.

Krebs

After glycolysis, if oxygen is present, what occurs?

Cytoplasm (cytosol)

Where does glycolysis take place?

2

How many ATP's are required to get glycolysis started?

Presence or absence of oxygen

After glycolysis, what determines which pathway pyruvic acid will follow?

2

What is the net production of ATP during glycolysis?

lactic acid

Muscle fatigue is caused when the process of fermentation produces

Oxygen

What is the final electron acceptor at the end of the Electron Transport Chain during cellular respiration?

Exhaled

What happens to the CO2 produced
when pyruvic acid is broken down?

Oxidized, reduced

In cell respiration, glucose is ____________, O2 is ______________. (oxidized or reduced?)

ETC

which biochemical pathway produces the most ATP?

Glycolysis

Which pathway is involved in cell respiration AND fermentation?

Glycolysis

Which pathway occurs with or without oxygen?

ETC & chemiosmosis

2 parts of Oxidative Phosphoryation

Chemiosmosis

Passive Transport, H+ moves thru ATP Synthase to provide free energy to make ATP.

2;2;2

TOTAL energy components at end of glycolysis? ( ? NADH, ? Pyruvate & ? ATP)

H+ thru ATP Synthase, down the concentration gradient

In chemiosmosis, the direct source of energy used to convert ADP to ATP.

ATP CO2 & ethyl alcohol

Yeast fermentation produces what 3 products?

NAHD & FADH2

Electon carriers in Citric Acid Cycle (Krebs)?

innermembrane

ETC pumps H+ ions into what part of mitochondria?

glucose

Yeast cells with defective mitochondria will breakdown what for energy?

Glycolysis & Krebs (citric acid cycle)

Where does substrate level phosphorylation occur?

photosynthesis (definition)

process of harnessing light energy to build carbohydrates in autotrophs (ex. plants, cyanobacteria)

photosynthesis (equation)

6 CO2 + 6 H2O + light energy --> C6H12O6 + 6 O2

autotroph

organism that can capture energy from sunlight or chemicals and use it to produce its own food (producer)

heterotroph

organism that cannot produce its own food and therefore obtains it by consuming other living things (consumer)

anabolic

What kind of a process is photosynthesis?

catabolic

What kind of a process is cellular respiration?

light-dependent reactions

1st step of photosynthesis during which light energy is captured and used to synthesize ATP and NADPH

light-independent reactions

2nd step of photosynthesis during which CO2 is incorporated into a sugar molecule using ATP and NADPH produced during the first step

thylakoid membranes of chloroplasts

location of light-dependent reactions

stroma of chloroplasts

location of light-independent reactions

G3P

carbon product of the light-independent reactions, which used to form glucose sugar. PGAL

absorption spectrum

graph of a pigment's ability to absorb various wavelengths of light

violet, blue and red

Which wavelengths of the visible light spectrum do chlorophylls absorb?

green and yellow

Which wavelengths of the visible light spectrum do chlorophylls reflect?

carotenoids

accessory pigments in chloroplasts that broaden the spectrum of colors used in photosynthesis

chlorophyll b

pigment, green/olive, in chloroplast

chlorophyll a

pigment, blue/green, in chloroplast

excited state

when absorbed photon energy causes electron to move away from nucleus

photosystems

photosynthetic pigments embedded with protein complexes in the thylakoid membrane