exam flascards

A set of flashcards covering key concepts from chapters on Energy, Enzymes, Cellular Respiration, and Photosynthesis.

Potential Energy

Stored energy based on position or structure.

Kinetic Energy

Energy of motion.

First Law of Thermodynamics

Energy cannot be created or destroyed, only transferred or transformed.

Second Law of Thermodynamics

Every energy transfer increases the disorder (entropy) of the universe.

Entropy

A measure of disorder or randomness in a system.

Endergonic Reaction

A reaction that absorbs energy (e.g., photosynthesis, dehydration synthesis).

Exergonic Reaction

A reaction that releases energy (e.g., cellular respiration, hydrolysis).

ATP

Adenosine triphosphate, composed of adenine, ribose, and three phosphate groups.

Phosphorylation

The addition of a phosphate group to a molecule.

Enzymes

Proteins that speed up chemical reactions by lowering activation energy.

Factors Affecting Enzyme Activity

Temperature, pH, substrate concentration.

Denaturation of Enzymes

High heat or extreme pH can denature enzymes.

Enzyme Activators

Molecules that increase enzyme activity.

Enzyme Inhibitors

Molecules that reduce enzyme activity.

Competitive Inhibitors

Bind to the active site of an enzyme.

Noncompetitive Inhibitors

Bind elsewhere on the enzyme, changing its shape.

Equation for Cellular Respiration

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + energy (ATP).

Exothermic

Refers to reactions that release energy, such as cellular respiration.

Redox Reaction

A reaction involving electron transfer—oxidation (loss) and reduction (gain).

Oxidizing Agent

The substance that gains electrons in a redox reaction.

Reducing Agent

The substance that loses electrons in a redox reaction.

Anaerobic

Referring to processes that occur without oxygen.

Aerobic

Referring to processes that occur with oxygen.

Types of Anaerobic Respiration

Lactic acid fermentation and alcohol fermentation.

Stages of Aerobic Respiration

Glycolysis, Pyruvate oxidation, Citric acid cycle, Electron Transport Chain (ETC).

Function of the ETC

Electrons pass through proteins, pumping H⁺ to create a gradient used by ATP synthase to synthesize ATP.

Chemiosmosis

The flow of H⁺ ions through ATP synthase to generate ATP.

ATP from Substrate-Level Phosphorylation

4 ATP (2 in glycolysis, 2 in citric acid Cycle).

ATP from Oxidative Phosphorylation

About 28 —> 30-32 ATP produced.

Mitochondria in Muscle/Liver Cells

These cells have more mitochondria, which produce more ATP.

Effects of ETC Disruption

Disruption of the ETC decreases or stops ATP production.

Common Elements of Photosynthesis and Cellular Respiration

Both use redox reactions, ETCs, and ATP synthase.

Chlorophyll Location in Plants

Most chlorophyll is located in the mesophyll tissue of leaves.

Stomata

Small openings in leaves for gas exchange (CO₂ in, O₂ out).

Structure of a Chloroplast

Composed of outer membrane, inner membrane, stroma, thylakoids, and grana.

Light-Dependent Reactions Location

Occur in the thylakoid membranes.

Light-Independent Reactions Location

Occur in the stroma (Calvin Cycle).

Main Photosynthetic Pigment

Chlorophyll a.

Higher Energy Wavelengths

Shorter wavelengths (like blue/violet) have more energy.

Equation for Photosynthesis

6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂.

Endothermic Nature of Photosynthesis

Photosynthesis is an endothermic process.

Reactants/Products of Light Reactions

Reactants: light, H₂O, NADP⁺, ADP; Products: O₂, ATP, NADPH.

Reactants/Products of Calvin Cycle

Reactants: CO₂, ATP, NADPH; Product: glucose.

Phases of the Calvin Cycle

Carbon fixation, reduction, regeneration.

Enzyme for Carbon Fixation

RuBisCO.

Turns of the Calvin Cycle for Glucose

6 turns are needed for the production of 1 glucose.

Plants and CO₂ Levels

Plants reduce CO₂ levels by absorbing it during photosynthesis.

CO₂ and Climate Change

CO₂ is a greenhouse gas that traps heat, contributing to global warming.