Overview
This review guide covers key ACP Biology concepts for final exam preparation, including biochemistry, cell structure, cellular energy, genetics, molecular biology, evolution, and ecology.
Molecules of Life & Enzymes
- Organic compounds contain carbon and are found in living things.
- Four main macromolecules: carbohydrates (e.g., glucose), lipids (e.g., fats), proteins (e.g., enzymes), nucleic acids (e.g., DNA).
- Carbohydrates provide energy, lipids store energy, proteins support structure and function, nucleic acids store genetic info.
- Monomers are single units; polymers are chains of monomers.
- Dehydration synthesis joins monomers, hydrolysis breaks polymers into monomers.
- Enzymes speed up chemical reactions by lowering activation energy.
- Enzymes bind substrates, form enzyme-substrate complex, convert substrates to products, and release them.
- Enzyme activity is affected by temperature, pH, and substrate concentration.
- Enzymes are proteins.
Cell Structure and Function
- Cells are small to maximize surface area to volume ratio for efficient exchange.
- Prokaryotes have no nucleus, eukaryotes have a nucleus and organelles.
- Major cell organelles: nucleus (control), mitochondria (energy), chloroplast (photosynthesis), cell membrane (barrier), ribosome (protein synthesis), etc.
- Plant cells have cell walls and chloroplasts; animal cells do not.
- Cell membrane is a fluid mosaic, allowing movement of proteins and lipids.
- Passive transport requires no energy (diffusion, osmosis); active transport uses energy.
- Osmosis: water moves from hypotonic (low solute) to hypertonic (high solute) until isotonic.
Cellular Energy/Photosynthesis and Cellular Respiration
- Autotrophs make their own food; heterotrophs consume others.
- Mitochondria produce ATP; chloroplasts conduct photosynthesis.
- Photosynthesis uses sunlight, COâ‚‚, and Hâ‚‚O to make glucose and Oâ‚‚.
- Only plants, algae, and some bacteria perform photosynthesis.
- Cellular respiration converts glucose and Oâ‚‚ into ATP, COâ‚‚, and Hâ‚‚O.
- All organisms perform respiration.
- ATP is the main energy currency of cells.
- Photosynthesis stores energy; respiration releases it.
The Cell Cycle and Mitosis
- DNA exists as chromatin during interphase and chromosomes during division.
- Cell cycle stages: interphase, mitosis (prophase, metaphase, anaphase, telophase), cytokinesis.
- Mitosis phases: prophase (chromosomes condense), metaphase (align), anaphase (separate), telophase (nuclear membranes form).
- Stem cells regenerate planaria.
- Autosomes are non-sex chromosomes; sex chromosomes determine gender.
- A karyotype shows all chromosomes in a cell.
- Asexual reproduction produces identical offspring; sexual reproduction increases variation.
Meiosis & Patterns of Inheritance
- Somatic cells are body cells (diploid); gametes are sex cells (haploid).
- Mitosis produces identical cells; meiosis makes unique gametes.
- Chromosomes are DNA structures; sister chromatids are identical copies; homologous pairs are similar chromosomes.
- Mendel discovered basic inheritance laws.
- Genotype is genetic makeup; phenotype is physical trait; dominant alleles mask recessive ones; heterozygous has two different alleles; homozygous has two same alleles.
- Punnett squares predict genetic outcomes.
- Inheritance patterns: complete, incomplete dominance, multiple alleles, codominance, X-linked traits.
Molecular Biology
- Franklin, Watson & Crick discovered DNA's double helix structure.
- DNA stores genetic information.
- DNA is a double helix made of nucleotides; RNA is single-stranded.
- DNA replication uses helicase (unwinds DNA) and DNA polymerase (builds new strands); replication is semiconservative.
- mRNA (messenger), tRNA (transfer), and rRNA (ribosomal) have different roles in protein synthesis.
- Transcription makes mRNA in the nucleus; translation makes proteins in the cytoplasm.
- CRISPR-Cas9 edits genes.
- Mutations can change genes or chromosomes, causing effects from silent to harmful.
Evolution
- Darwin's natural selection: variation, overproduction, competition, survival of the fittest.
- Darwin proposed natural selection, Lamarck suggested acquired traits.
- Evidence for evolution includes fossils, anatomy, and DNA.
- Homologous structures have similar origins; analogous structures serve similar functions.
- Vestigial structures are unused features (e.g., human appendix).
- The Biological Species Concept defines species as groups that interbreed.
Ecology
- Levels: biosphere > biome > ecosystem > community > population > organism.
- Biotic factors are living; abiotic are nonliving parts of ecosystems.
- Types of symbiosis: mutualism, commensalism, parasitism.
- Producers make food; consumers eat others; decomposers break down dead matter.
- Niche is an organism’s role; habitat is its environment.
- Trophic level is an organism's position in the food chain.
- Energy flows up trophic levels, only 10% transferred each step.
- Keystone species maintain ecosystem balance.
- The carbon cycle moves carbon among atmosphere, organisms, and Earth; humans impact it by burning fossil fuels.
- Climate change is caused by increased greenhouse gases; data analysis tracks trends.
Key Terms & Definitions
- Enzyme — protein that catalyzes chemical reactions.
- Osmosis — diffusion of water across a membrane.
- ATP — molecule used by cells for energy.
- Photosynthesis — process converting sunlight to chemical energy in plants.
- Mitosis — cell division producing identical cells.
- Meiosis — cell division producing gametes.
- Genotype — organism’s genetic makeup.
- Phenotype — observable traits of an organism.
- Mutation — change in DNA sequence.
- Symbiosis — close relationship between species.
- Keystone species — species with critical ecosystem role.
Action Items / Next Steps
- Review class notes and previous review sheets.
- Create flashcards for weak areas.
- Study diagrams of cell structures and processes.
- Complete up to assigned page for each review day.
- Practice using Punnett squares and reading codon charts.