Andy's BIO FINAL STUDY LOCK IN

ATP Hydrolysis

Breaking ATP using water to release energy

Exergonic Reaction

Releases energy (ΔG < 0)

Endergonic Reaction

Requires energy input (ΔG > 0)

Energy Coupling

Using energy from one reaction to drive another

ATP Cycle

Continuous formation and breakdown of ATP

Catalyst

Speeds up a reaction without being consumed or changing ΔG

Enzyme

A protein that acts as a biological catalyst

Activation Energy (Ea)

Minimum energy required to start a reaction

Transition State (TS)*

Highest energy, unstable state where bonds break and form

Substrate

Reactant that an enzyme acts upon

Active Site

Region of an enzyme where the substrate binds

Cofactor

Non-protein helper molecule, often a metal ion

Coenzyme

Organic helper molecule, often vitamin-derived

Optimal pH

pH at which an enzyme works best

Optimal Temperature

Temperature at which enzyme activity is highest

Inhibitor

Molecule that reduces or stops enzyme activity

Irreversible Inhibitor

Permanently disables an enzyme

Reversible Inhibitor

Temporarily inhibits an enzyme

Competitive Inhibitor

Binds active site and competes with substrate

Noncompetitive Inhibitor

Binds regulatory site and alters enzyme shape

Allosteric Regulation

Control of enzyme activity through binding at a non-active site

Feedback Inhibition

Final product inhibits earlier enzymes in its pathway

Anabolic Pathways

Consume energy theu build large molescule out of smaller ones

Catabolic Pathways

releases energy by breaking down large molecules into smaller ones

Energy Coupling

Energy released from catabolic pathways is used to drive anabolic pathways any excess energy is usually stored as ATP which is used to power other reactions

Endergonic

Is positive this reaction is NOT favored it moves away from equilibrium and it takes in energy it is also seen as non-spontaneous

Exergonic

Is negative is seen as spontaneous which means the reaction is favorable and is moves it towards equilibrium its also releases energy

Dehydration Reaction

Builds molecules by removing water

Hydrolysis

Breaks molecules by adding water

Phosphorylation

Addition of a phosphate group (–PO₄)

Carboxylation

Addition of a carboxyl group (–COOH)

Redox Reaction

Reaction involving electron transfer

Oxidation

Loss of electrons

Reduction

Gain of electrons

Hydride Ion (H⁻)

Hydrogen carrying an extra electron

Proton (H⁺)

Hydrogen that donates an electron

Catabolism

Breakdown of molecules to release energy

Aerobic Respiration

Oxygen-dependent energy production

Anaerobic Respiration

Oxygen-independent, low-energy production

The Three Phases of Respiration

1. Glycolysis

• Breaks 1 glucose (6C) → 2 pyruvate (3C)

• Occurs in cytoplasm

• Anaerobic (does NOT require O₂)

2⃣ Citric Acid Cycle (Krebs / TCA)

• Completes oxidation of pyruvate

• Occurs in mitochondrial matrix

3⃣ Oxidative Phosphorylation

• Uses high-energy electrons to make ATP

• Two steps:

  1. Electron Transport Chain (ETC)

  2. Chemiosmosis

Pyruvate Decarboxylation (The Shunt Step)

Products (per glucose)

• 2 CO₂

• 2 NADH

• 2 acetyl-CoA

NAD⁺

Electron carrier that becomes NADH when reduced

NADH

Reduced form of NAD⁺ carrying high-energy electrons

Oxidoreductase

Enzyme that catalyzes redox reactions

Dehydrogenase

Enzyme that removes or adds hydrogen

Glycolysis

Anaerobic breakdown of glucose into pyruvate

Pyruvate Decarboxylation

Conversion of pyruvate into acetyl-CoA

Citric Acid Cycle (Krebs)

Completes oxidation of carbon and generates electron carriers

Oxidative Phosphorylation

ATP production using ETC and chemiosmosis

Electron Transport Chain (ETC)

Series of proteins that transfer electrons and pump protons

Chemiosmosis

ATP production driven by proton flow through ATP synthase

ATP Synthase

Enzyme that produces ATP using proton gradient

Final Electron Acceptor

Oxygen in aerobic respiration

Fermentation

Regenerates NAD⁺ when oxygen is absent

Heterotrophs

(other feeders”) Obtain organic molecules by consuming other organisms.

Autotrophs

(“self feeders”) Produce their own organic molecules.

Photoautotrophs

Use photosynthesis to convert solar energy into chemical energy.

Leaves

primary site of photosynthesis

Mesophyll

internal leaf tissue rich in chloroplasts

Stomata

pores that allow:

• CO₂ to enter

• O₂ to exit

Chlorophyll

green pigment that absorbs light energy

Thylakoids

flattened membrane sacs that contain chlorophyll

Stroma

fluid interior surrounding thylakoids

C4 plants

separation by space

CAM plants

separation by time

 The mesophyll layer of the leaf plays a significant role in trapping light energy from the sun upon which photosynthesis mostly takes place in this layer. Why is this so?

Contains a high concentration level of chloroplast

 What are the products of the light-dependent reaction used to power the light independent reaction? 

NADPH and ATP

Cellular respiration starts with glycolysis, which occurs in the cytoplasm producing two pyruvate molecules. Which of the following processes will allow cellular respiration to proceed in case oxygen is absent?

Anaerobic respiration

How many ATP molecules are needed to split glucose into two pyruvate molecules?

2 ATP 

Why does the Calvin cycle need the products from the light reaction phase?

To convert carbon dioxide into sugar

Which of the following shows the correct order during cellular respiration?

Glycolysis → Krebs cycle →Electron transport chain

The movement of which ion across the membrane space to the matrix, NAD+ causes ATP synthase to spin and make ATP.

H+ ions

The ATP made during glycolysis is generated by:

Substrate-level phosphorylation

Which process in eukaryotic cells will proceed normally whether oxygen (O2) is present or absent?

Glycolysis 

How are photosynthesis and cellular respiration related to each other?

The products of one process are the reactant of the other.

When a pigment molecule absorbs a photon, one of its electrons ______

1. Gain energy

2. Becomes excited

3. Transition into an unstable state

4. Raised from the ground to excited state

5. All of the above

Sunlight is a type of ___________ energy

Electromagnetic radiation

The Calvin cycle involves all the following except: 

Formation of waste products in the form of CO2

Which of the following are produced during the Calvin cycle?

Glucose, ADP, NADP+

The electrons lost from the reaction center of photosystem I are replaced by electrons from

H2O

The oxygen consumed during cellular respiration is directly involved in which process or event?

The citric acid cycle

Which of the following is true? 

Photosynthesis occurs in chloroplasts and cellular respiration in mitochondria.

Which one of the following metabolic pathways is common in aerobic and anaerobic organisms? 

Glycolysis

During chemiosmosis, _______________

ATP is synthesized when H+ ions move through a protein transport provided by ATP synthase

Muscle soreness associated with strenuous exercise is at least partly due to ________. 

The presence of lactic acid produced during fermentation in muscle cells.

Write the chemical reaction of photosynthesis (Balance the equation and label the reactants and products)

6CO2 + 6H20 + Light energy —-> C6H12O6 + 6O2

Write the chemical reaction of cellular respiration (Balance the equation and label the reactants and products)

C6H12O6 + 6O2 —> 6CO2 + 6H20 + ATP

When and why does our body use lactic acid fermentation? 

When oxygen is low, muscle cells switch from aerobic respiration to anaerobic respiration (lactic acid fermentation) to keep making ATP, producing lactic acid as a byproduct.

Noncompetitive inhibitor

the substrate binds to the active site without any complications from the inhibitor molecule. The inhibitor molecules bind to the regulatory site, which provided for it.

Competitive inhibitor

The inhibitor competes with the substrate for the active site, which can negatively impact the cell’s function.