quiz energy enzymes and cell resp.

energy

capacity to cause change or do work

Kinetic energy

energy associated with motion

thermal energy

kinetic energy associated with random movement of atoms and moleucles

(heat energy - thermal energy in transfer between objects

potential energy

energy that matter possesses bc of its location and structure

Chemical energy

potential energy that can be released during a chemical reaction

Conservation of E / First law of thermodynamics

Energy cannot be created or destroyed but converted from one form to another

Thermodynamics

study of energy and transformations

Closed system

unable to exchange energy or matter with its surroundings

cannot reach equilibrium

open system

can exchange E and matter w surroundings

cells and organisms are open systems

Second law of thermodynamics

Every energy transfer increases entropy (disorder) in the universe

Entropy

Measure of molecular disorder, randomness (heat has the most)

Free energy

energy that can do work when temp and pressure are uniform, as in a living cell

chem reactions are going to proceed in direction that causes a loss of free E

more free E is less stable but has greater work capacity

Potential e →

Kinetic E (thermal, kinetic)

Exergonic

proceeds with a net release of free E and is spontaneous

is favorable

need exergonic for endogonic

Endergonic/Endogonic

absorbs free energy from surroundings - non spontaneous

unfavored and requires energy to be done

Metabolism

combined catabolic and anabolic pathways

Catabolic

break apart

Anabolic

link together

three types of work cells do

chemical work

transport work

mechanical work

ATP

cells energy shuttle, makes RNA

made of ribose, adenine, and 3 phosphate groups'

breaks down glucose

ATP hydrolysis

breaks phosphate group off from energy, can be undone/added back

Enzymes

end in -ase

helps with reaction, catalyst, does NOT get used up during reaction, (reused)

Catalysis

reaction enabled by a catalyst

Substrate

reactant that enzyme binds to (The thing that goes INTO the enzyme, the thing that changes during reaction)

Active site

WHERE the substrate bonds to the enzyme

An active site can lower an energy barrier by

Orienting substrate correctly

straining substrate bonds

providing a favorable microenvironment

covalently bonding to the substrate (CHARGES HAVE TO LINE UP)

Enzyme activity can be affected by

temp

pH

chemicals like cofactors and inhibitors

Cofactors

non protein enyzme helper

may be inorganic (metal in ionic form) or organic

organic ones are called coenzymes (vitamins)

Competitive inhibitors

bind to active site, making reaction impossible

noncompetitive inhibitors

binds to another parts of enzyme causing indirect impacts to reaction

Allosteric regulation

is good and bad

may either inhibit or stimulate an enzymes activity

occurs when a regulatory molecule binds to a protein at one site and affects the proteins function at another site

cooperativity

a form of allosteric regulation that can amplify enzyme activity

simplified image

balanced chem eq. for cell respiration

Glucose + 6O2 → 6h2o + 6co2 + atp

O2 is reduced (gains e-)

glucose is oxidized (loses e-)

inputs and outputs glycolysis

input - glucose, 2 NAD+, 2 ATP, 4 ADP,

output - 2 (3 carbon) pyruvates, 2 NADH, 4ATP

Important details - G3P is in the middle of the glucose to pyruvate transformation lol

Input and output of pyruvate oxidation

inputs: 2 pyruvates, 2 NAD+, 2 coA

outputs: 2 acetly coA, 2 co2, 2 NADH

NO ATP!

inputs n outies for citric acid cycle

inputs: 2 acetly coA, 3NAD+, 1 FAD, 1 ADP

outies: 2 CO2, 3NADH, 1 FADH2, 1ATP, protons released to make gradient

Oxaloacetate + Acetyl group = ?

citric acid

activated carriers and their groups carried

ATP - phosphate groups

NADH, NADPH, FADH2 - electrons and hydrogens

Acetly Co-enzyme A - acetyl group

kinase

catalyzes the addition of a phosphate group to substrate

isomerase

rearranges chemical bonds by changing isomer

dehydrogenase

removes a hydrogen

mutase

moves chemical functional group

Where are the electrons in the ETC from?

the e-s come from NADH and FADH2, which is very important for phosphorylation oxidation

phosphorylation oxidation (i cant be bothered to type it out rn)

THE LASt electron acceptor issssssss?

O2 to make H2O 🥳

proton pumping

produces a steep electrochemical proton gradient across the inner mitochondrial membrane

ATP synthase

enzyme, Uses energy stored in electrochem. gradient to make ATP

chemiosmosis

the use of energy in a proton gradient to drive cellular work

this is important

glucose → NADH → electrons to the ETC → proton motive force → ATP

Overall how much ATP per glucose?

Around 32 ATP per glucose, but about 34% of the energy in a glucose molecule is transferred to ATP during cell resp. the rest is lost as heat ☹

Aerobic respiration

consumes organic molecules and O2 to yield ATP

Fermentation

Partial degradation of sugars that occurs without O2 (anaerobic)

Anaerobic resp.

consumes compounds other than o2

When is O2 used in the cell respiration cycle?

It is only used in the last step in the ETC chain to turn the 6o2 into water (the glucose makes CO2)

Which step of cell resp. is not in the mitochondria?

Glycolysis - it is in the cytoplasm

Where is pyruvate oxidation?

mitochondrial matrix

Where is citric acid cycle?

Mito. matrix

Where is Oxidative phosphorylation

in the mitochondria inner membrane

What is the point of fermentation

It is to regenerate NADH to NAD+ for glycolysis

How is photosynthesis a cycle?

Light Energy → photosynthesis → organic molecules and O2 → cellular respiration → CO2 + H2O which then gets released back into ecosystem

know how to draw diagrams on a mitochondrion, chloroplast, and the diagram for cell resp. and photosynthesis

hehe

Light reactions in thylakoid (membrane)

1. Split h2o !!!!!!

2. release o2

3. reduce the e- acceptor NADP+ to NADPH

4. Generate ATP from ADP by photophosphorylation

The ‘captured’ Energy from light reactions used by carbon fixation

PSII

Absorbs light to take apart water

Transfers e- through proton pump (makes concen gradient)

ATP synthase brings protons back to stroma

Stroma → thylakoid space

PSI

On membrane thylakoid

Absorbs light

e- passed through pumps and gets added to NADP+→NADPH

Calvin cycle

Uses the CO2 to make glucose (or other organic compounds)

Inputs 3CO2 per cycle

there is 6ATP and 6 NADPH to phosphoglycerate

1 G3P is immediate output of cycle

9 ATP used altogether

Rubisco

enzyme that puts the CO2 onto molecules in calvin cycle

G3P in photosyn. why important

It can be used to start cellular respiration since G3P is a crucial step in glycolysis

Gases move freely in chloroplasts becasue?

simple diffusion

How do gasses get to cells deep within the leaf?

Cells can separate their pore-guard cells, they breathe

What happens if CO2 isnt avaliable for calvin cycle?

The cell will input O2 into the calvin cycle, but it can’t make G3P with O2, so it is a waste of energy and O2

C4 plants

made of 4c molecule, minimize the cost of photorespiration by incorporating CO2 into four Carbon compounds

Pep carboxylase

make the 4carbon compounds that can be converted to pyruvate + CO2

CAM Plants/Crassulacean acid metabolism

take in compounds in a time sensitive way

They only open their stomata at night, meaning they only breathe in CO2 at night, so H2O doesn’t get evaporated

has stomata closed during the day