final bio

Chapter 1: The Science of Biology

• Eight Characteristics of Life:
  • Organization: Living things are structured from cells to systems (e.g., cells, tissues, organs, systems in humans).
  • Reproduction: Living organisms reproduce (e.g., bacteria by binary fission).
  • Growth and Development: Organisms increase in size and complexity over time (e.g., seed to tree).
  • Energy Use (Metabolism): Living things use energy (e.g., plants through photosynthesis).
  • Response to Stimuli: Organisms react to their environment (e.g., sunflowers facing sunlight).
  • Homeostasis: Maintaining a stable internal environment (e.g., human body temperature regulation).
  • Adaptation through Evolution: Populations change over generations (e.g., antibiotic resistance).
  • Genetic Code: DNA carries hereditary information (e.g., traits passed from parents).
• Homeostasis Definition: The process of maintaining a stable internal environment, like temperature or pH regulation.
• Quantitative Observations: Observations involving numbers or measurements (e.g., plant height of 30 cm).
• Qualitative Observations: Descriptive observations without measurements (e.g., a leaf is green).
• Experimental Setup/Group: The experimental group exposed to a specific variable.
• Steps of the Scientific Method (Order): Observation, Question, Hypothesis, Experiment, Data Collection and Analysis, Conclusion, Communication of Results.

Chapter 2: The Chemistry of Life

• Element Definition: A pure substance made of one type of atom (examples: O, C, H).
• Activation Energy: Energy needed to start a chemical reaction.
• Buffer: Substance that maintains stable pH by neutralizing acids or bases.
• Acids: Substances with a pH less than 7 (e.g., vinegar).
• Bases: Substances with a pH greater than 7 (e.g., soap).
• Protein Functions: Catalysing enzymes, structural support, transport, cell communication (hormones).
• Amino Acid Definition: Building blocks of proteins.
• Carbohydrate Functions: Energy storage (glucose, starch), structural support (plant cellulose).
• Nucleic Acid Functions: Store and transfer genetic information (DNA, RNA).
• Lipid Functions: Energy storage, insulation, membrane formation.
• Solution Definition: A homogeneous mixture (e.g., saltwater).
• Solvent Definition: The dissolving substance (e.g., water).
• Solute Definition: The dissolved substance (e.g., salt).
• Water Molecule: Two hydrogen atoms, one oxygen atom; a polar molecule due to unequal charge distribution.

Chapter 7: Cell Structure and Function

• Cell Theory:
  • All living things are made of cells.
  • Cells are the basic unit of life.
  • All cells come from pre-existing cells.
• Eukaryotic vs. Prokaryotic Cells: Eukaryotic cells have a nucleus and organelles, prokaryotic cells do not; both have DNA, cell membranes, and cytoplasm.
• Organelle Functions:
  • Nucleus: Stores DNA.
  • Mitochondria: Energy production.
  • Chloroplast: Photosynthesis (plants);
  • Ribosomes: Protein synthesis.
• Hypertonic, Hypotonic, and Isotonic Solutions:
  • Hypertonic: Higher solute outside, cell shrinks.
  • Hypotonic: Higher solute inside, cell swells.
  • Isotonic: Equal concentration, no change.
• Diffusion and Osmosis:
  • Diffusion: Movement of particles from high to low concentration (no energy).
  • Osmosis: Diffusion of water.
• Active Transport: Movement of substances against a concentration gradient (energy required).
• Hydrophobic: Water-repelling.
• Hydrophilic: Water-attracting.

Chapter 23: Plant Structure and Function

• Photosynthesis Layer in Leaves: Occurs in the mesophyll.
• Stomata Function: -Allow gas exchange (CO₂ in, O₂ out).
  • When open-Gas exchange and water loss.
  • When closed—Conserves water.
• Angiosperm Reproductive Parts:
  • Male: Stamen (anther and filament).
  • Female: Pistil (stigma, style, ovary).
• Seed Dispersal Methods: Wind, water, animals, mechanical ejection.

Chapter 8: Photosynthesis

• Photosynthesis Equation: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂
• ATP Function: Provides energy for cellular processes.
• Photosynthesis Organelle: Chloroplast.
• Chlorophyll Function: Captures light energy (reflects green light).
• Light Reaction:
  • Reactants: Light, water, ADP, NADP⁺.
  • Products: Oxygen, ATP, NADPH.
• Calvin Cycle:
  • Reactants: CO₂, ATP, NADPH.
  • Products: Glucose.

Chapter 9: Cellular Respiration and Fermentation

• Cellular Respiration Equation: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + energy (ATP)
• Organisms: Eukaryotes and some prokaryotes.
• Cellular Respiration Organelle: Mitochondria.
• Cellular Respiration Stages: Glycolysis, Krebs Cycle, Electron Transport Chain.
• Oxygen Requirement: Yes.
• Products: ATP, CO₂, H₂O.
• Fermentation Types:
  • Lactic Acid Fermentation: Produces lactic acid.
  • Alcoholic Fermentation: Produces ethanol and CO₂.

Chapter 10: Cell Growth and Division

• Interphase Stages:
  • G₁: Cell growth.
  • S: DNA replication.
  • G₂: Preparation for mitosis.
• Sister Chromatids and Centromeres:
  • Sister Chromatids: Identical chromosome copies.
  • Centromere: Region connecting sister chromatids.
• Mitosis Stages (Order): Prophase, Metaphase, Anaphase, Telophase.
• Spindle Fibers Role: Separate chromosomes.
• Cytokinesis: Division of cytoplasm.

Chapter 12: DNA

• DNA Structure Discoverers: Watson, Crick, Franklin.
• Nucleotide Components: Phosphate, sugar, nitrogenous base (A, T, C, G).
• Base Pairing: A-T, C-G.
• DNA Replication: Unwinding, base pairing, joining; enzymes include DNA helicase, DNA polymerase and ligase.

Chapter 13: RNA and Protein Synthesis

• RNA Nucleotides: Adenine, Uracil, Cytosine, Guanine (A, U, C, G).
• RNA Base Pairing: A-U, C-G.
• Transcription: DNA → RNA.
• Translation: RNA → Protein.
• mRNA: Carries genetic code from DNA.
• tRNA: Carries amino acids.
• Codons: Three-nucleotide sequences on mRNA.
• Anticodon: Complementary sequence on tRNA.
• Central Dogma: DNA → RNA → Protein.