BIO 189 CHAPTER 3

Energy and metabolism / Releasing chemical energy

What is energy?

Capacity to do work.

What is work?

Result of energy transfer.

First law of thermodynamics?

Energy cannot be created or destroyed

Second law of thermodynamics?

Energy disperses and some is lost as heat.

What type of energy is stored in chemical bonds?

Potential energy.

What happens to cells in hypotonic solution?

Swell.

What is turgor?

Pressure against wall in plants.

What molecules cross lipid bilayers easily?

Gases, water, small nonpolar molecules.

What molecules need transport proteins?

Most ions and large molecules.

What is passive transport?

Movement without ATP.

Does passive transport require ATP?

No

Example of passive transport?

Glucose transport.

What is active transport?

Movement using ATP.

Does active transport require ATP?

Yes.

Example of active transport?

Calcium pump.

What is endocytosis?

Cell takes materials in.

What is exocytosis?

Cell releases materials.

What is phagocytosis?

Cell eating.

What is simple diffusion?

Molecules move high → low concentration.

What is facilitated diffusion?

Movement through proteins.

What are mitochondrial diseases?

Genetic diseases affecting mitochondria.

Symptoms of mitochondrial diseases?

Blindness, deafness, weakness

What is cellular respiration?

Pathways making ATP using electron transfer chain.

Why is aerobic respiration risky?

Free radicals.

What are free radicals?

Reactive molecules damaging cells.

What is oxidative stress?

Damage caused by free radicals.

What does anaerobic mean?

Without oxygen.

What does aerobic mean?

With oxygen.

Aerobic respiration equation?

C₆H₁₂O₆ + O₂ → CO₂ + H₂O + 36 ATP

What is fermentation?

Anaerobic breakdown of molecules.

Does fermentation make more or less ATP?

Less ATP.

What is glycolysis?

Glucose → 2 pyruvate + ATP.

Where does glycolysis happen?

Cytoplasm.

What pathway starts aerobic respiration and fermentation?

Glycolysis.

What is aerobic respiration?

Oxygen pathway producing ATP.

What does aerobic respiration require?

Oxygen.

What does aerobic respiration produce?

CO₂ + water + ATP.

Steps after glycolysis?

Acetyl-CoA → Citric acid cycle → Electron transfer phosphorylation.

What is alcoholic fermentation?

Anaerobic pathway producing ethanol.

Alcoholic fermentation converts pyruvate into what?

Ethanol.

Examples of alcoholic fermentation?

Bread, wine, beer.

What is lactate fermentation?

Anaerobic pathway producing lactate.

Lactate fermentation converts pyruvate into what?

Lactate.

Examples of lactate fermentation?

Yogurt, muscles, cheese.

How much ATP does fermentation make?

2 ATP.

Where does fermentation occur?

Cytoplasm.

What happens to NAD+ during fermentation?

Regenerated.

Which muscle fibers use lactate fermentation?

Fast-twitch fibers.

Activities using lactate fermentation?

Sprinting, weight lifting.p

Energy through the biosphere flows in what direction?

One direction

What is a reaction?

Process of chemical change.

What is a reactant?

Molecule entering a reaction.