Biology Exam Review Flashcards

Vocabulary flashcards for Biology Exam Review

Cell Theory Component 1

States that all living organisms are composed of one or more cells.

Cell Theory Component 2

States that the cell is the basic unit of structure and organization in organisms.

Cell Theory Component 3

States that all cells arise from pre-existing cells.

Cell Wall

A rigid outer layer present in plant cells but not in animal cells.

Chloroplasts

Organelles responsible for photosynthesis, found in plant cells but not in animal cells.

Central Vacuole

A large storage structure in plant cells, smaller in animal cells.

Nucleus

The control center of the cell, containing DNA.

Ribosome

Site of protein synthesis.

Endoplasmic Reticulum (ER)

Network of membranes involved in protein and lipid synthesis.

Vesicle

Small membrane-bound sac used for transport.

Golgi Apparatus

Modifies, packages, and ships proteins.

Vacuole

Stores nutrients, wastes, and water.

Active Transportt

Transport that requires energy to move substances against their concentration gradient.

Endocytosis

Cell engulfs material into a vesicle.

Exocytosis

Vesicle fuses with membrane to release material outside the cell.

Active Transport

Transport that requires energy.

Passive Transport

Transport that does not require energy.

Isotonic Solution

Equal solute concentration, no net water movement.

Hypertonic Solution

Higher solute concentration outside the cell, water exits and cell shrinks.

Hypotonic Solution

Lower solute concentration outside the cell, water enters and cell swells.

Disaccharide Synthesis

Process where two monosaccharides join via a condensation reaction forming a glycosidic bond.

Carbohydrates Function

Quick energy source and structural support.

Lipids Function

Long-term energy storage, insulation, cell membrane structure.

DNA

Double-stranded, deoxyribose sugar, stores genetic information.

RNA

Single-stranded, ribose sugar, involved in protein synthesis.

DNA Base Pairs

Adenine pairs with Thymine, Cytosine pairs with Guanine.

Carbohydrates Function

Energy

Lipids Function

Energy storage, membranes

Proteins Function

Enzymes, structure, transport

Nucleic Acids Function

Genetic information

Saturated Fats

No double bonds, solid at room temperature.

Unsaturated Fats

Double bonds, liquid at room temperature.

Nucleotide Sequence to Amino Acid Sequence

DNA is transcribed to mRNA, which is translated into amino acids at the ribosome.

Denaturation

Protein loses shape due to heat or pH.

Coagulation

Denatured proteins clump together.

Benedict's Test

Used to test for sugar.

Iodine Test

Used to test for starch.

Biuret Test

Used to test for protein.

Sudan Red Test

Used to test for lipids.

Cellular Respiration

Converts glucose to ATP.

Aerobic Respiration

respiration with oxygen.

Anaerobic Respiration

Without oxygen.

ATP

Primary energy currency of the cell.

Unique Properties of Water

High heat capacity, cohesion/adhesion, polarity, solvent abilities.

Condensation Reaction

Joining molecules, releasing water.

Dehydration Synthesis

Same as condensation reaction.

Hydrolysis

Breaking molecules using water.

Catabolic Reactions

Breaking molecules down.

Isomer

Compounds with the same formula but different structures.

Proton Gradient

Difference in proton concentration across a membrane, used to generate ATP.

Chemiosmosis

Use of proton gradient to power ATP synthase and produce ATP.

Macromolecule Linkage - Protein

peptide bond

Macromolecule Linkage - Carb

Carb: glycosidic bond.

Lipid

ester bond.

Nucleic Acid

phosphodiester bond.

Protein Folding

Primary, secondary, tertiary, and quaternary structure, stabilized by H-bonds, ionic bonds, and disulfide bridges.

DNA Structure

Double helix, sugar-phosphate backbone, base pairs.

ATP

Universal energy molecule.

REDOX Reactions

Reduction = gain of electrons, oxidation = loss. Seen in respiration and photosynthesis.

Enzyme Function

Speed up reactions by lowering activation energy.

Enzyme Inhibition/Regulation

Competitive, non-competitive inhibitors; allosteric sites.

Anaerobic vs Aerobic Organisms

Aerobic uses oxygen; anaerobic does not.

Substrate Level vs Oxidative Phosphorylation

direct ATP formation vs via ETC and ATP synthase.

Glycolysis

In: Glucose; Out: 2 pyruvate, 2 ATP, 2 NADH.

Mitochondria

Double membrane, matrix, cristae. Site of aerobic respiration.

Pyruvate Oxidation

Converts pyruvate to acetyl-CoA, produces CO2 and NADH.

Krebs Cycle Products

2 CO2, 3 NADH, 1 FADH2, 1 ATP per acetyl-CoA.

ETC Gradient

Pumps protons to intermembrane space.

Gradient Use

Protons flow through ATP synthase to make ATP.

Oxygen

Final electron acceptor in ETC.

No Oxygen in Cellular Respiration

Fermentation occurs (lactic acid or ethanol).

Chloroplast Structure

Outer membrane, thylakoids, stroma.

Light Reactions

Electron flow drives proton gradient; makes ATP/NADPH.

Water/Light Role in Photosynthesis

Water splits to provide electrons; light excites them.

Light Reactions/Calvin Cycle Link

ATP/NADPH from light reactions power Calvin cycle.

Calvin Cycle Products

G3P (used to form glucose).

Significance of G3P and RuBP

building block for sugars, or CO2 acceptor regenerated each cycle.

Anti-Parallel Nature of DNA

DNA strands run in opposite directions: one 5’→3’, the other 3’→5’.

Complimentary Base Pairing and DNA Backbone

A–T (2 H-bonds), C–G (3 H-bonds); backbone made of sugar and phosphate.

Semi-Conservative Replication

Each new DNA molecule has one old and one new strand.

DNA Replication Process

Enzymes: Helicase (unwinds), DNA polymerase (builds), Ligase (joins fragments), Primase (lays RNA primer).

Okazaki Fragments

Short DNA segments on the lagging strand synthesized discontinuously.

Central Dogma

DNA → RNA → Protein.

DNA vs RNA

double-stranded, thymine, deoxyribose. vs single-stranded, uracil, ribose.

RNA Types

mRNA (messenger), tRNA (transfer), rRNA (ribosomal).

DNA Encoding for Protein

Transcription: DNA → mRNA (RNA polymerase). Translation: mRNA → protein (ribosome, tRNA).

Codon and Anticodon

3-base mRNA sequence; vs complementary 3-base tRNA sequence.

Post-Transcriptional Modifications

5’ cap, poly-A tail, splicing out introns.

Control of Protein Synthesis

1. Transcriptional control, 2. mRNA processing control, 3. Translational control, 4. Post-translational control.

Operon System

Prokaryotic gene regulation: consists of promoter, operator, genes (e.g., lac operon).

Types of Mutations

Point, insertion, deletion; frameshift (insertion/deletion) most dangerous.

Restriction Endonuclease

Enzyme that cuts DNA at specific sequences.

Gel Electrophoresis

Separates DNA fragments by size using electrical current.

Plasmid

Small circular DNA in bacteria used for genetic engineering.

Homeostasis

Maintenance of internal balance despite external changes.

Positive vs Negative Feedback

Negative: reverses change (e.g., sweating). Positive: amplifies change (e.g., childbirth).

Heat/Cold Stress Response

Heat: sweat, vasodilation. Cold: shiver, vasoconstriction.

Ammonia, Urea, Uric Acid

Produced by protein breakdown; excreted by kidneys/liver.

Nephron Structure

Glomerulus, Bowman's capsule, tubules, loop of Henle, collecting duct.

Urine Formation

1. Filtration: blood to nephron, 2. Reabsorption: nutrients reabsorbed, 3. Secretion: additional wastes added.