NYSTCE Biology CST cheat sheet

Biology Content Domain

• Macromolecules: carbohydrates (C:H:O ≈ 1:2:1) supply quick energy; lipids are hydrophobic, energy-dense, and form membranes; proteins are amino-acid polymers with diverse functions; nucleic acids store and transmit genetic information.

• Enzymes lower activation energy and are not consumed; activity peaks at an optimum pH and temperature, and denaturation above that optimum irreversibly alters the active site.

• Cell theory: all living things are made of cells, the cell is the basic unit of life, and all cells arise from pre-existing cells.

• Prokaryotic cells lack a membrane-bound nucleus and organelles; eukaryotic cells compartmentalize functions into a nucleus, mitochondria, chloroplasts, and endomembrane system.

• ATP is the universal energy currency; glycolysis occurs in the cytoplasm, the Krebs cycle in the mitochondrial matrix, and oxidative phosphorylation on the inner mitochondrial membrane.

• Photosynthesis: light reactions in the thylakoid membrane produce ATP and NADPH and release O2 from water; the Calvin cycle in the stroma fixes CO2 using RuBisCO.

• DNA replication is semiconservative; transcription makes mRNA from a DNA template; translation at the ribosome reads codons (three bases) into amino acids.

• Mendelian genetics: alleles segregate during meiosis, and independent assortment applies to genes on different chromosomes; a Punnett square predicts offspring genotype ratios.

• Evolution by natural selection requires heritable variation, differential reproductive success, and change in allele frequencies across generations; Hardy-Weinberg equilibrium describes a non-evolving population.