Cumulative Midterm AP Biology Outline

Cumulative Midterm AP Biology Outline

I. Phylogenetic Tree Concepts

Phylogenetic Tree

• Definition: A diagram showing evolutionary relationships among biological species based on genetic and/or physical trait similarities and differences.

• Components:

  • Nodes: Represent common ancestors.

    • Internal nodes indicate divergence points where a species split into two.

  • Branches: Represent evolutionary pathways and relationships.

    • Length of branches often correlates with the time elapsed since divergence.

  • Sister Taxa: Groups sharing a most recent common ancestor.

Cladogram

• Definition: A diagram that organizes species based on shared derived traits, highlighting differences among groups.

• Purpose: Useful for analyzing relationships without indicating time or genetic distance.

II. Study of Life

Eukaryotes vs. Prokaryotes

• Eukaryotes: Have membrane-bound organelles and a nucleus (e.g., plants, animals, fungi, protists).

• Prokaryotes: Lack membrane-bound organelles; no nucleus (e.g., bacteria, archaea).

Domains of Life

1. Bacteria: Prokaryotic organisms; found in diverse environments.

2. Archaea: Prokaryotic; often live in extreme conditions.

3. Eukarya: Includes all eukaryotic organisms.

Kingdoms

• Protista: Diverse group including algae and protozoa.

• Fungi: Decomposers; includes yeasts, molds, and mushrooms.

• Plantae: Multicellular, photosynthetic organisms.

• Animalia: Multicellular, heterotrophic organisms.

III. Ecology

Overview

• Definition: Study of interactions between living organisms and their environment.

• Factors:

  • Biotic: Living components (e.g., plants, animals).

  • Abiotic: Nonliving components (e.g., temperature, water).

Levels of Organization

1. Population: Group of the same species in an area.

2. Community: Different populations interacting.

3. Ecosystem: Community plus abiotic factors.

4. Biome: Large ecosystems characterized by climate (e.g., desert, tundra).

5. Biosphere: All ecosystems on Earth.

Population Dynamics

• Patterns of Distribution:

  • Clumped: Grouped in clusters.

  • Uniform: Evenly spaced.

  • Random: No specific pattern.

• Population Strategies:

  • K-strategists: Fewer offspring, high parental care.

  • R-strategists: Many offspring, low parental care.

• Survivorship Curves:

  • Type I: High survival in early/midlife, decline later (e.g., humans).

  • Type II: Constant survival rate (e.g., birds).

  • Type III: Low early survival, but those that survive live long (e.g., fish).

Growth Models

• Exponential Growth: Rapid increase without limits.

• Logistic Growth: Growth slows as population reaches carrying capacity.

Community Relationships

1. Symbiosis:

   • Mutualism: Both benefit (e.g., bees and flowers).

   • Commensalism: One benefits, other unaffected (e.g., barnacles on whales).

   • Parasitism: One benefits, other is harmed (e.g., ticks on animals).

2. Predation: Predator-prey interactions.

3. Competition: Organisms compete for resources.

IV. Biochemistry

Types of Bonds

1. Ionic: Transfer of electrons.

2. Covalent: Sharing of electrons.

3. Hydrogen: Weak bonds between polar molecules.

Properties of Water

• Polarity: Allows hydrogen bonding.

• Key Properties:

  • Excellent solvent.

  • High heat capacity.

  • High heat of vaporization.

  • Cohesion (surface tension).

  • Adhesion (capillary action).

  • Ice less dense than liquid water.

Macromolecules

1. Carbohydrates:

   • Function: Energy source, structural support.

   • Monomer: Monosaccharides (e.g., glucose).

   • Examples: Starch, glycogen, cellulose.

2. Lipids:

   • Function: Energy storage, membrane structure.

   • Types: Fats, oils, phospholipids, steroids.

   • Structure: Hydrophilic head, hydrophobic tail (phospholipids).

3. Proteins:

   • Function: Enzymes, structural components.

   • Monomer: Amino acids.

   • Structure: Primary, secondary, tertiary, quaternary levels.

4. Nucleic Acids:

   • Function: Genetic information storage and transfer.

   • Monomer: Nucleotides.

   • Examples: DNA (double-stranded), RNA (single-stranded).

Enzymes

• Function: Catalysts that lower activation energy.

• Specificity: Enzyme-substrate binding.

• Factors Affecting Activity: Temperature, pH, denaturation.

V. Cells

Prokaryotic vs. Eukaryotic Cells

• Prokaryotes: Smaller, no nucleus, fewer organelles.

• Eukaryotes: Larger, nucleus, complex organelles.

Key Organelles

• Nucleus: Control center; houses DNA.

• Mitochondria: Powerhouse; produces ATP.

• Endoplasmic Reticulum (ER):

  • Rough ER: Protein synthesis.

  • Smooth ER: Lipid synthesis.

• Golgi Apparatus: Processes and packages proteins.

• Lysosomes: Digestive enzymes.

• Cytoskeleton: Provides structure (microtubules, microfilaments).

• Plasma Membrane: Phospholipid bilayer; controls transport.

Transport Mechanisms

• Passive Transport: Diffusion, osmosis (no energy required).

• Active Transport: Uses energy (e.g., sodium-potassium pump).

VI. Bioenergetics

Metabolism

• Catabolism: Breakdown of molecules (releases energy).

• Anabolism: Synthesis of molecules (requires energy).

ATP (Adenosine Triphosphate)

• Structure: Adenine, ribose, three phosphates.

• Function: Primary energy carrier.

• Conversion: ATP → ADP + Pi (releases energy).

Cellular Respiration

1. Glycolysis:

   • Occurs in cytoplasm.

   • Breaks glucose into two pyruvate molecules.

   • Produces 2 ATP (net) and 2 NADH.

2. Citric Acid Cycle (Krebs Cycle):

   • Occurs in mitochondria.

   • Produces NADH, FADH2, and ATP.

3. Electron Transport Chain:

   • Uses NADH and FADH2 to create a proton gradient.

   • Drives ATP production via ATP synthase.

Key Processes

• Chemiosmosis: Proton gradient powers ATP synthesis.

• Oxidation-Reduction Reactions:

  • Oxidation: Loss of electrons.

  • Reduction: Gain of electrons.