BIO 111 Exam Study Guide

Flashcards for review.

What is energy?

The ability to do work or cause change.

What are the two main forms of energy?

Kinetic (energy of motion) and potential (stored energy).

What is the difference between a calorie and a Calorie?

calorie (lowercase) raises 1g of water by 1°C; Calorie (uppercase) = 1,000 calories = 1 kilocalorie.

What is the First Law of Thermodynamics?

Energy cannot be created or destroyed.

What is the Second Law of Thermodynamics?

Energy transformations increase entropy (disorder).

What is entropy?

A measure of disorder; systems tend toward higher entropy naturally.

What is a metabolic pathway?

A series of reactions that build or break molecules.

Define endergonic reaction.

Requires energy input (e.g., photosynthesis).

Define exergonic reaction.

Releases energy (e.g., cellular respiration).

Define oxidation.

Loss of electrons.

Define reduction.

Gain of electrons.

What is an electron transport chain?

Series of proteins that pass electrons and gradually release energy, used in photosynthesis and cellular respiration.

What is the structure of ATP?

Adenine + ribose + 3 phosphate groups.

What is the function of ATP?

Stores and releases energy.

How is energy released from ATP?

Breaking the bond to the third phosphate group → ADP + Pi.

What is phosphorylation?

Adding a phosphate to a molecule (e.g., ADP → ATP).

What are enzymes?

Biological catalysts that speed up chemical reactions.

What is the active site of an enzyme?

The site where the substrate binds.

What factors affect enzyme activity?

Temperature, pH, salt concentration.

What are cofactors?

Inorganic helpers for enzymes (e.g., metal ions).

What are coenzymes?

Organic helpers for enzymes (e.g., vitamins).

Describe negative feedback in enzyme regulation.

End product inhibits the enzyme/pathway.

Describe positive feedback in enzyme regulation.

Product enhances production.

What is a competitive inhibitor?

Binds to active site.

What is a noncompetitive inhibitor?

Binds elsewhere and changes enzyme shape.

What is a concentration gradient?

Difference in concentration across a membrane.

What is passive transport?

No energy required (simple diffusion, osmosis, facilitated diffusion).

What is active transport?

Requires ATP to move substances against gradient.

What are the two types of bulk transport?

Endocytosis and exocytosis.

What are the two types of endocytosis?

Phagocytosis (solid) and pinocytosis (liquid).

What is exocytosis?

Releases materials out of the cell.

What is the equation for photosynthesis?

CO₂ + H₂O + sunlight → glucose + O₂

What part of the cell does photosynthesis occur in?

Chloroplasts, mainly in leaf cells.

What is the main pigment used in photosynthesis?

Chlorophyll a.

Name two accessory pigments used in photosynthesis.

Chlorophyll b, carotenoids.

Where are pigments located in the chloroplast?

Thylakoid membranes.

What are thylakoids?

Flattened sacs where light reactions occur.

What are grana?

Stacks of thylakoids.

What is the stroma?

Fluid where carbon reactions occur.

What occurs in Photosystem II?

Absorbs light, splits water → O₂ + electrons + H⁺.

What occurs in Photosystem I?

Uses electrons to make NADPH.

How is ATP made in the light reactions?

Using ATP synthase and the H⁺ gradient (chemiosmosis).

What are the three stages of the Calvin Cycle?

1. Carbon fixation 2. PGAL synthesis 3. RuBP regeneration

What are the inputs of the Calvin Cycle?

CO₂, ATP, NADPH.

What is the output of the Calvin Cycle?

Glucose (via PGAL).

What is photorespiration?

Occurs when O₂ is used instead of CO₂ – wastes energy.

What are C3 plants?

Most common; not efficient in hot/dry climates.

What are C4 plants?

Adapted to avoid photorespiration (e.g., corn).

What are CAM plants?

Open stomata at night to conserve water (e.g., cacti).

What is the goal of cellular respiration?

Make ATP from glucose.

What is aerobic respiration?

Uses O₂ as the final electron acceptor.

What is anaerobic respiration?

Uses other molecules instead of O₂.

What are the three stages of aerobic respiration?

1. Glycolysis 2. Krebs Cycle 3. Electron Transport Chain (ETC)

What are the inputs and outputs of Glycolysis?

Glucose → 2 pyruvate + 2 ATP + 2 NADH

What are the inputs and outputs of the Krebs Cycle?

Pyruvate → CO₂ + NADH + FADH₂ + 2 ATP

What occurs during the Electron Transport Chain (ETC)?

NADH/FADH₂ donate electrons. Oxygen is final electron acceptor → H₂O. About 32 ATP made via ATP synthase.

What is the total ATP yield per glucose in aerobic respiration?

36–38 (varies).

How does anaerobic respiration differ from aerobic respiration?

Similar to aerobic but doesn’t use oxygen, uses different final electron acceptors, less efficient (fewer ATP made).

What is fermentation?

No oxygen required. Only glycolysis occurs → 2 ATP per glucose.

What are the two types of fermentation?

Alcoholic (glucose → ethanol + CO₂) and lactic acid (glucose → lactate).

Why is glycolysis considered an ancient pathway?

Universal, doesn't require O₂ or organelles.

How are photosynthesis and respiration interlinked?

Photosynthesis stores energy (in glucose). Respiration releases energy (as ATP).

What is the unit of life?

The cell – smallest structure capable of performing all life processes.

What are the three parts of the Cell Theory?

1. All living things are made of cells. 2. Cells are the basic unit of structure and function. 3. All cells come from pre-existing cells.

What is taxonomy?

The science of naming, describing, and classifying organisms.

List the 8 levels of Taxonomic Hierarchy in order.

1. Domain 2. Kingdom 3. Phylum 4. Class 5. Order 6. Family 7. Genus 8. Species

What is an element?

A pure substance with only one kind of atom.

Give four examples of bulk elements.

C, H, O, N

Give two examples of trace elements.

Fe, Zn

Name the three subatomic particles and their charges.

Proton (+), Neutron (0), Electron (-)

Define ions.

Charged atoms.

Define isotopes.

Atoms of the same element with different numbers of neutrons.

What are radioactive isotopes?

Unstable nuclei that emit radiation.

What is the valence shell?

Outer shell—determines reactivity.

Name the three types of chemical bonds.

Covalent, Ionic, Hydrogen Bonds

List four properties of water.

Cohesion, adhesion, high heat capacity, solvent abilities, ice floats.

What is an acid?

pH < 7, donates H⁺.

What is a base?

pH > 7, accepts H⁺.

What is a neutral pH?

pH = 7.

What is the range of the pH scale?

0-14.

What is the definition of an organic molecule?

Contains carbon and hydrogen.

What is a monomer?

Small unit (e.g., glucose, amino acid).

What is a polymer?

Chain of monomers.

Describe dehydration synthesis.

Links monomers, releases water.

Describe hydrolysis.

Breaks polymers, uses water.

What are the monomers of carbohydrates?

Monosaccharide (e.g., glucose).

What are the monomers of proteins?

Amino acid.

What type of bond links amino acids?

Peptide bond.

List the four levels of protein structure

Primary, Secondary, Tertiary, Quaternary

What is denaturation?

Loss of structure/function due to environment.

List four types of lipids.

Fats, oils, phospholipids, steroids.

What is the monomer of nucleic acids?

Nucleotide (sugar, phosphate, base).

Give two examples of nucleic acids.

DNA, RNA.

What is the function of the phospholipid bilayer?

Semi-permeable membrane of cells.

What is the difference between prokaryotes and eukaryotes?

Prokaryotes: No nucleus (bacteria, archaea). Eukaryotes: With nucleus (plants, animals, fungi, protists).

Name the three domains of life.

Bacteria, Archaea, Eukarya.

What is the function of the nucleus?

Contains DNA.

What are the two types of Endoplasmic Reticulum (ER)?

Rough ER (makes proteins) and Smooth ER (makes lipids).

What is the function of the golgi apparatus?

Modifies and ships proteins/lipids.

What is the function of the mitochondria?

Makes ATP (energy).