AP Biology Test Unit 3: Cellular Energy

Competitive inhibitors

inhibition and substrates are in competition with each other and are racing to bond with the enzyme first at the active site

Non-competitive inhibitors

Bonds to allosteric site to allosteric site so the substrate cannot fit into the active site OR inhibitor bonds to allosteric site and shanges shape of the active site

Activation energy

WITH an enzyme the activation energy is lower and the reaction happens quicker than WITHOUT an enzyme

Temperature effect on enzyme activity

higher temp = higher activity. It leads to more frequent collisions between enzymes and substrates up to an optimal temperature.

pH effect on enzyme activity

Enzyme activity is dependent on pH, with each enzyme having an optimal pH range. Deviations from this range can lead to decreased activity or denaturation.

Concentration effect on enzyme activity

Increasing enzyme concentration increases the reaction rate as long as substrates are available.

Evolution of glycolysis

Glycolysis is believed to be one of the earliest metabolic pathways, demonstrating the evolutionary adaptation of organisms to efficiently extract energy from glucose in the absence of oxygen. (Organisms have been doing it ever since they started a long long time ago)

What might alter the shape of an enzyme?

An allosteric reaction(inhibitor molecules binding to the enzyme), denaturation, extreme temps, pH levels, and induced fit (natural binding of substrate) can cause temporary change.

What is oxygen’s primary role in cellular respiration?

To act as the final electron acceptor in the electron transport chain. It accepts electrons to form water (H2O), enabling ATP production

Mitochondria- structure

It is a double membraned structure (where Cellular respiration occurs), outer membrane controls what enters and inner membrane is folded into cristae to maximize surface area for ATP synthesis and the matric is where the Krebs cycle occurs.

Mitochondria- function

The mitochondria's primary function is to generate ATP through oxidative phosphorylation and the Krebs cycle, providing energy for cellular activities. It also contains the citric acid cycle/fermentation also happens here and the electron transport chain.

Chloroplast- structure

Chloroplasts are double-membrane organelles that contain thylakoids arranged in stacks called grana, suspended in a fluid called stroma. They are the sites of photosynthesis, converting light energy into chemical energy.

Chloroplast- function

They convert light energy into chemical energy through photosynthesis. Sunlight is captured and used to synthesize glucose. It uses carbon dioxide and water then rel

Meaning of being phosphorylation

The process of adding a phosphate group . It can active or deactivate enzymes. It can also cause the enzyme to store or release energy such as in the conversion of ADP to ATP.

What colors wavelengths of light are most useful to plants?

Blue (425-450nm) and red (600-700nm)

Absorption spectrum

Shows what each pigment absorbs at different wavelengths of light, indicating their efficiency in capturing light energy for photosynthesis. (doesn’t really absorb green or yellow well because it’s reflected by plants)

Action spectrum

How much oxygen is being released, there is not a lot from green and yellow because their wavelengths aren’t very effective at promoting photosynthesis

ETC in photosynthesis- location, what does it do, light reactions

In thylakoid membrane- light energy excites electrons in PSII and they are transferred through a series of proteins, ultimately leading to the production of ATP and NADPH. This process occurs during the light-dependent reactions of photosynthesis, anerobic

ETC in respiration- location, what does it do, light reactions

Inner mitochondrial membrane- protein complex within this membrane pumps protons from the mitochondrial matrix to the inter membrane space, creating a gradient that drives ATP synthesis. Anaerobic process and relies on glucose, light dependent

Respiration Lab- peas and crickets

Warmer temps are good for higher respiration, because the higher temps cause more reactions/collisions of substrates and enzymes which results in higher enzyme activity.

Coenzymes

Organic, helps an enzyme and substrates dock, helps with activation (getting an enzyme to work vs inhibition which is slowing down or stopping the enzyme’s function)

Lactic acid/alcoholic fermentation

An anaerobic process that converts glucose into energy, producing lactic acid in muscles or ethanol and carbon dioxide in yeast.

Cyclic electron flow

A pathway in photosynethsis where electrons cycle around PSI, generating ATP but not NADPH. Involves a return to the original state.

Noncyclic electron flow

A linear process in photosynthesis where energized electrons travel from water thru PSII, an ETC, and finally PSI to produce ATP and NADPH. Moves forward without repetition like a one way chemical reaction.

Summerize Engelmann’s experiment

action spectrum of light energy. Engelmann's experiment used aerobic bacteria to determine the action spectrum of photosynthesis, showing which wavelengths of light were most effective for driving the process. (Red 600-700nm) and Blue (400-500nm) GREEN and YELLOW BAD. Longer wavelengths = lower energy, and high energy= shorter wavelengths

Catabolic pathways

Break down complex molecules into simpler ones, releasing energy that is used to produce ATP for cellular functions

Induced fit for enzyme and substrate binding

Describes how an enzyme/s active site changes shape upon binding with a substrate to create a tighter, more precise fit. NOT LOCK AND KEY

Chemimosmosis and ATP Synthase

The process in which energy from a proton gradient is used to make ATP, with the proton flow occurring through a channel in the enzyme ATP synthase

the final acceptor the ETC that functions in aerobic oxidative phosphorylation is oxygen

Oxygen is the final electron acceptor in the ETC during aerobic oxidative phosphorylation.