Cell Structure and Function

Cell Structure and Function

• Eukaryotes have a nucleus and are larger, while prokaryotes lack a nucleus and are smaller.
• Domains: Bacteria, Archaea, Eukarya. Eukarya contains eukaryotic organisms; Bacteria and Archaea are prokaryotic.
• Nucleus: Contains DNA and RNA, responsible for cell growth and reproduction.
• Mitochondria: Produce energy through respiration.
• Ribosomes: Sites of protein synthesis.
• Lysosomes: Contain digestive enzymes.
• Golgi Body: Modifies, packages, and transports proteins.
• Smooth Endoplasmic Reticulum: Creates lipids (fats).
• Cytoplasm: Fluid inside the cell, suspends organelles.
• Cell Wall: Rigid layer outside the cell membrane, found in plant cells.
• Cell Membrane: Controls what enters and leaves the cell.
• Plant Cells: Have a cell wall, chloroplasts, and a large central vacuole.
• Animal Cells: Lack cell walls, chloroplasts, and large central vacuoles.

Reproduction and Genetics

• Crossing Over (Recombination): Exchange of genetic material between homologous chromosomes during meiosis, increasing genetic diversity.
• Meiosis: Produces haploid cells (gametes, half the chromosome number of the parent cell).
• Mitosis: Produces 2 identical diploid cells (same chromosome number).
• Sexual Reproduction: Involves two parents.
• Asexual Reproduction: No partner needed.
• Common Ancestry: Organisms share similar genes/characteristics, implying a common ancestor.
• Punctuated Equilibrium: Evolution occurring in rapid bursts, interrupted by long periods of stability.
• Gradualism: Evolution through slow, continuous change over time.

Taxonomy and Classification

• Taxonomy: The science of classifying organisms.
• Binomial Nomenclature: Naming system using two names (genus and species).
• Domain: Largest, most general taxonomic level.
• Species: Smallest, most specific taxonomic level.
• Dumb Kids Playing Catch On Freeways Get Squished: Mnemonics for taxonomic hierarchy: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

Evolution and Ecology

• Natural Selection: Organisms adapt to their environment through selective pressures.
• Coevolution: Two species impacting each other's evolution.
• Symbiotic Relationships: Parasitism (one harmed, one benefits), Predation (one eats the other), Mutualism (both benefit), Commensalism (one benefits, one unaffected).
• Adaptation: Inherited trait that enhances survival and reproduction in a specific environment.
• Speciation: Formation of new species from existing ones due to reproductive isolation.
• Reproductive Barriers (Isolation Mechanics): Mechanisms that prevent interbreeding between species
• • Behavioral Isolation: Differences in courtship or mating behaviors. • Temporal Isolation: Reproducing at different times. • Geographic Isolation: Physical barriers between populations. • Anatomic Isolation: Incompatible reproductive parts.
• Density-Dependent Factors: Environmental influences affected by population size (e.g., competition, disease).
• Density-Independent Factors: Environmental influences not affected by population size (e.g., natural disasters).
• Abiotic Factors: Non-living components of an ecosystem (e.g., temperature, sunlight).
• Biotic Factors: Living components of an ecosystem (e.g., plants, animals).
• Carrying Capacity: Maximum population size an environment can support.
• Exponential Growth: Population growth at a constant rate.
• Logistic Growth: Population growth slows down and eventually stabilizes due to environmental limitations.
• Survivorship Curve: Graph showing survival rates at each age.

Photosynthesis

• Photosynthesis: Conversion of light energy to chemical energy (glucose).
• Photosynthesis Equation: CO₂ + H₂O + Light Energy → C₆H₁₂O₆ + O₂
• Light-Dependent Reactions: Occur in thylakoids.
• Light-Independent Reactions (Calvin Cycle): Occur in the stroma; converts CO₂ into glucose using ATP and NADPH.

Cell Processes

• DNA replication must occur before mitotic cell division to maintain the same chromosome number in daughter cells.

Metric Conversions

• King Henry Died By Drinking Chocolate Milk: Mnemonic for metric prefixes (kilo, hecto, deca, base unit, deci, centi, milli).

Energy Transfer

• Pyramid of Energy: Depicts energy transfer between trophic levels (producers to tertiary consumers).

Other Key Concepts

• Autotrophs: Organisms that produce their own food (e.g., plants).
• Heterotrophs: Organisms that consume other organisms for energy (e.g., animals).
• Herbivores: Eat only plants.
• Carnivores: Eat only animals.
• Omnivores: Eat both plants and animals.
• Scavengers: Eat dead organisms.
• Detritivores: Eat dead organic matter.
• Decomposers: Break down dead organic matter.
• Microscope Magnification: Total magnification = Eyepiece magnification × Objective magnification.
• Pearson Correlation Coefficient (R-value): Measures the strength and direction of a linear relationship between two variables. (+1 strong positive, -1 strong negative).

Other

• Microscope Field Diameter Calculation: (Magnification 1 × Diameter 1) = (Magnification 2 × Diameter 2)