Comprehensive Biology Honors Final Exam Study Guide

Chapter 1: Biology – The Study of Scientific Life

1.1 What is Life?

• Characteristics of Life: All living things share certain properties, including organization, metabolism, homeostasis, growth, reproduction, response to stimuli, and adaptation. Example: Plants grow toward light (response to stimulus).

• Homeostasis: The maintenance of a stable internal environment. Example: Human body temperature regulation.

• Unicellular vs. Multicellular: Unicellular organisms consist of one cell (e.g., Amoeba), while multicellular organisms have many cells (e.g., humans).

• Autotrophs vs. Heterotrophs: Autotrophs produce their own food (e.g., plants via photosynthesis); heterotrophs consume other organisms (e.g., animals).

1.4–1.5 The Process of Science

• Scientific Method: Involves making observations, forming hypotheses, conducting experiments, and analyzing data.

• Hypothesis: A testable statement; can be null (no effect) or alternative (effect expected).

• Experimental Design: Includes control group, independent (manipulated) variable, and dependent (responding) variable.

• Claim, Evidence, Reasoning (CER): A framework for scientific explanation.

• Data Interpretation: Ability to read graphs and analyze results is essential.

Chapter 2: The Chemical Basis of Life

2.8–2.14 Water Properties

• Cohesion: Attraction between water molecules (e.g., water droplets).

• Adhesion: Attraction between water and other substances (e.g., water climbing plant stems).

• Surface Tension: The 'skin' on water's surface due to cohesion.

• Capillary Action: Movement of water up narrow tubes, important for plant transpiration.

• Transpiration: Loss of water from plant leaves, driven by cohesion, adhesion, and capillary action.

Chapter 3: The Molecules of Cells

3.1, 3.3–3.8, 3.12–3.14 Biomolecules

• Organic vs. Inorganic Compounds: Organic compounds contain carbon and hydrogen (e.g., glucose); inorganic do not (e.g., water).

• Major Biomolecules:

  • Carbohydrates: Energy source and structure (e.g., cellulose in plants).

  • Lipids: Long-term energy storage, cell membranes (e.g., fats, phospholipids).

  • Proteins: Structure, enzymes, transport (e.g., keratin in hair).

  • Nucleic Acids: Store genetic information (DNA, RNA).

• Elements in Biomolecules: CHONPS (Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur).

• Monomers and Polymers: Monomers are building blocks (e.g., amino acids for proteins); polymers are chains of monomers.

• Protein Folding: Structure determines function; denaturation disrupts function.

• Hydrolysis vs. Dehydration Synthesis: Hydrolysis breaks polymers (adds water); dehydration synthesis forms polymers (removes water).

• Energy Storage: Chemical bonds in organic molecules store energy.

Chapter 4: A Tour of the Cell & Chapter 5: The Working Cell

4.2–4.18 Cell Structure

• Cell Walls: Found in plants, fungi, bacteria; not in animal cells.

• Cell Membranes: Present in all cells; regulate entry/exit of substances.

• Eukaryotes vs. Prokaryotes: Eukaryotes have a nucleus and organelles (e.g., plants, animals); prokaryotes lack a nucleus (e.g., bacteria).

• Organelles: Specialized structures (e.g., mitochondria, chloroplasts, nucleus) with distinct functions.

5.1 Plasma Membrane

• Components: Phospholipid bilayer, proteins, cholesterol, carbohydrates.

• Membrane Proteins: Transport, signaling, cell recognition.

5.3–5.9 Membrane Transport

• Diffusion: Movement from high to low concentration.

• Osmosis: Diffusion of water across a selectively permeable membrane.

• Concentration Gradient: Difference in concentration; affects diffusion rate.

• Solution Types:

  • Hypertonic: Higher solute outside; cell loses water.

  • Hypotonic: Lower solute outside; cell gains water.

  • Isotonic: Equal solute; no net water movement.

• Active vs. Passive Transport: Passive (no energy, e.g., diffusion); active (requires energy, e.g., sodium-potassium pump).

• Facilitated Diffusion: Passive transport via proteins (e.g., glucose transport).

5.12–5.13 ATP & Enzymes

• ATP: Main energy currency of the cell.

• Enzymes: Biological catalysts; lower activation energy, increase reaction rate; specific to substrates; affected by temperature and pH.

• Denaturation: Loss of enzyme structure and function due to extreme conditions.

Chapter 6: How Cells Harvest Chemical Energy

6.1–6.8, 6.11 Cellular Respiration

• Stages: Glycolysis (anaerobic), Krebs Cycle (aerobic), Electron Transport Chain (aerobic).

• Reactants & Products: Glucose and oxygen produce carbon dioxide, water, and ATP.

• ATP Yield: Aerobic respiration produces more ATP than anaerobic.

• Formulas:

  • Cellular Respiration: $\mathrm{C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + ATP}$

  • Photosynthesis: $\mathrm{6CO_2 + 6H_2O + light \ energy \rightarrow C_6H_{12}O_6 + 6O_2}$

Chapter 7: Photosynthesis

7.2–7.5 Photosynthesis Overview

• Source of Energy: Sunlight.

• Energy Transformations: Light energy to chemical energy (glucose).

• Light Reactions: Occur in thylakoid membranes; produce ATP and NADPH.

• Calvin Cycle: Occurs in stroma; uses ATP/NADPH to fix CO2 into glucose.

• Chloroplasts: Site of photosynthesis; mitochondria for respiration.

Chapter 8: The Cellular Basis of Reproduction and Inheritance

8.1, 8.3–8.10 Mitosis & Cell Cycle

• Cell Division: Process by which cells reproduce.

• Parent/Daughter Cells: Parent cell divides to form genetically identical daughter cells (mitosis).

• Asexual vs. Sexual Reproduction: Asexual (one parent, identical offspring); sexual (two parents, genetic variation).

• Somatic Cells vs. Gametes: Somatic = body cells; gametes = sex cells (sperm/egg).

• Cell Cycle: Interphase (G1, S, G2), Mitosis, Cytokinesis.

• Mitosis: Prophase, Metaphase, Anaphase, Telophase; results in two diploid cells.

• Chromosome Numbers: Humans: 46 in somatic, 23 in gametes.

8.12–8.20 Meiosis

• Meiosis: Produces haploid gametes; increases genetic variation via crossing over and independent assortment.

• Terms: Haploid (n), diploid (2n), crossing over, homologous pairs, zygote.

• Autosomes vs. Sex Chromosomes: Autosomes = non-sex chromosomes; sex chromosomes determine gender.

• Karyotype: Visual display of chromosomes; used to detect abnormalities (e.g., nondisjunction).

Chapter 9: Patterns of Inheritance

9.2–9.5 Mendelian Genetics

• Mendel: Father of genetics; studied pea plants.

• Key Terms: Heredity, trait, gene, homozygous, heterozygous, dominant, recessive, Law of Segregation.

• P, F1, F2 Generations: Parental, first filial, second filial generations.

• Punnett Squares: Used to predict genotype and phenotype ratios for monohybrid and dihybrid crosses.

• Genotype vs. Phenotype: Genetic makeup vs. physical expression.

• Common Ratios: 3:1 (monohybrid), 9:3:3:1 (dihybrid).

9.8 Pedigrees & Sex-Linked Traits

• Pedigree Analysis: Traces inheritance patterns; autosomal dominant/recessive, sex-linked traits.

• Sex-Linked Inheritance: Traits on X or Y chromosomes; often show different patterns in males and females.

9.11–9.14 Non-Mendelian Inheritance

• Incomplete Dominance: Heterozygote shows intermediate phenotype.

• Codominance: Both alleles expressed (e.g., AB blood type).

• Multiple Alleles: More than two forms of a gene (e.g., ABO blood types).

• Rh Factor: Another blood antigen; important in transfusions.

• Karyotype & Nondisjunction: Chromosome number abnormalities (e.g., Down syndrome).

9.20–9.21 Sex-Linked Traits

• Sex-Linked Punnett Squares: Used for traits on X or Y chromosomes.

Chapter 10: Molecular Biology of the Gene

10.2–10.3 DNA & RNA Structure

• DNA vs. RNA: DNA is double-stranded, deoxyribose sugar; RNA is single-stranded, ribose sugar.

• Genetic Code: Sequence of DNA bases determines traits.

• Nucleotide Structure: Phosphate, sugar, nitrogenous base.

• Bonds: Covalent bonds in backbone; hydrogen bonds between bases.

• Base Pairing: DNA: A–T, C–G; RNA: A–U, C–G (Chargaff’s rule).

10.4–10.5 DNA Replication

• Purpose: Copy DNA before cell division; occurs in nucleus.

• Leading vs. Lagging Strand: Continuous vs. discontinuous synthesis.

10.6–10.13 Protein Synthesis

• Central Dogma: DNA → RNA → Protein.

• Transcription: DNA to mRNA in nucleus.

• Translation: mRNA to protein at ribosome; tRNA brings amino acids.

• Codons & Anticodons: Codons (mRNA triplets); anticodons (tRNA triplets).

• Mutations: Changes in DNA sequence; can alter protein function.

10.16 Locations & Functions

• Replication: Nucleus.

• Transcription: Nucleus.

• Translation: Cytoplasm/ribosome.

• Three Bases (Codon): Code for one amino acid.

Chapter 12: DNA Technology and Genomics

• Restriction Enzymes: Cut DNA at specific sequences.

• Gel Electrophoresis: Separates DNA fragments by size; used to compare evolutionary relationships.

Chapter 13: How Populations Evolve

13.1–13.5 Adaptation & Evidence

• Adaptations: Traits that improve survival/reproduction.

• Evidence for Evolution: Fossils, homologous/vestigial structures, biochemistry.

13.6–13.8 Natural Selection

• Darwin’s Theory: Organisms with advantageous traits survive and reproduce.

• Requirements: Variation, inheritance, differential survival, reproduction.

• Genetic Variation: Mutation, gene shuffling.

• Key Terms: Mutation, gene pool, fitness, allele frequency.

13.9–13.11 Hardy-Weinberg Principle

• Hardy-Weinberg Equilibrium: Describes non-evolving populations; five conditions (no mutation, migration, selection, large population, random mating).

• Equation: $p^2 + 2pq + q^2 = 1$ and $p + q = 1$

13.12–13.14 Types of Selection

• Directional Selection: Favors one extreme.

• Stabilizing Selection: Favors intermediate traits.

• Disruptive Selection: Favors both extremes.

Chapter 15: Tracing Evolutionary History

• Derived Characters: Traits shared by a group, used in cladistics.

• Kingdom Characteristics: Cell type, nutrition, multicellularity.

• Cladograms/Phylogenetic Trees: Show evolutionary relationships.

• Determining Common Ancestry: Morphology, molecular data, biotechnology.

Chapters 20–23, 28–29: Animals & Body Systems

Chapter 20: Animal Structure & Function

• Feedback Loops: Negative feedback maintains homeostasis; positive feedback amplifies changes.

Chapter 21: Nutrition & Digestion

• Alimentary Canal: Mouth → esophagus → stomach → small intestine → large intestine → anus.

• Chemical vs. Mechanical Digestion: Mechanical (chewing, stomach churning); chemical (enzymes, begins in mouth for carbs).

• Digestive Enzymes: Amylase (carbs), protease (proteins), lipase (fats).

• Peristalsis: Muscle contractions move food.

Chapter 22: Gas Exchange

• Respiratory Pathway: Nose → pharynx → larynx → trachea → bronchi → lungs.

• Negative Pressure Breathing: Diaphragm contracts, air drawn in.

• Feedback Loops: CO2 levels regulate breathing via nervous/circulatory systems.

Chapter 23: Circulation

• Blood Flow: Pulmonary (heart–lungs–heart), systemic (heart–body–heart).

• Arteries vs. Veins: Arteries carry blood away from heart; veins return blood.

• Blood Pressure: Normal ~120/80 mmHg; high/low readings indicate health issues.

• Blood Components: Red cells (O2), white cells (immunity), platelets (clotting), plasma (fluid).

Chapter 28: Nervous Systems

• Neuron Structure: Dendrite, cell body, axon, synapse.

• Impulse Pathway: Dendrite → cell body → axon → synapse.

• Action Potential: Electrical signal; neurotransmitters transmit across synapse.

• Brain Regions: Cerebrum (thinking), cerebellum (movement), midbrain, hindbrain.

Chapters 31–33: Plants

Chapter 31: Plant Structure & Function

• Plant Kingdom: Multicellular, autotrophic, cell walls (cellulose).

• Structures: Roots (absorption), shoots (support), root hairs (increase surface area).

• Tissues: Vascular (xylem: water; phloem: sugars), dermal (protection), guard cells/stomata (gas exchange).

• Cuticle: Waxy layer prevents water loss.

• Leaf & Flower Structure: Specialized for photosynthesis and reproduction.

Chapter 32: Plant Nutrition & Transport

• Transpiration: Water loss via leaves; driven by cohesion, adhesion, capillary action.

• Stomata: Open/close to regulate gas exchange and water loss; affected by water pressure.

Chapter 33: Control Systems in Plants

• Plant Hormones: Auxin controls phototropism (growth toward light).

• Tropisms: Phototropism (light), gravitropism (gravity), thigmotropism (touch).

• Darwin’s Experiment: Showed tips of shoots sense light.

Chapters 34 & 37: Ecology

Chapter 34: The Biosphere

• Ecology: Study of interactions among organisms and their environment.

• Biotic vs. Abiotic Factors: Living vs. nonliving components.

• Levels of Organization: Population, community, ecosystem, biosphere.

• Ultimate Energy Source: Sunlight.

• Law of Conservation: Energy and matter are neither created nor destroyed.

Chapter 37: Communities & Ecosystems

• Symbiotic Relationships: Mutualism (+/+), predation (+/–), parasitism (+/–), herbivory (+/–), commensalism (+/0).

• Trophic Levels: Producers, consumers (primary, secondary, tertiary, quaternary), decomposers.

• Biomass: Total mass of living matter at each trophic level.

• Food Chains vs. Food Webs: Chains are linear; webs are interconnected.

• 10% Rule: Only ~10% of energy is transferred to next level; 90% lost as heat.

• Limiting Factors: Density-dependent (e.g., disease), density-independent (e.g., weather).

• Carrying Capacity: Maximum population an environment can support.

• Predator-Prey Cycles: Populations fluctuate in response to each other.

• Competition: Intraspecific (within species), interspecific (between species).

• Keystone Species: Disproportionate effect on ecosystem stability.

• Trophic Cascades: Changes at one trophic level affect others (e.g., Yellowstone wolves).

Term	Definition	Example
Autotroph	Organism that produces its own food	Plant
Heterotroph	Organism that consumes others for food	Animal
Osmosis	Diffusion of water across a membrane	Water entering a plant root
Enzyme	Protein catalyst that speeds up reactions	Amylase in saliva
Gene	Segment of DNA coding for a trait	Gene for eye color
Mutation	Change in DNA sequence	Sickle cell allele
Producer	Organism that makes its own food	Grass
Consumer	Organism that eats others	Wolf

Additional info: This guide synthesizes key concepts from each major chapter, providing definitions, examples, and essential processes. For deeper understanding, refer to diagrams, practice problems, and lab experiences as indicated in your course materials.