Biology Unit 1A: Characteristics of Organisms

Unit 1A: Characteristics of Organisms

• Organisms grow and develop over time.
• Organisms respond to their environment.
• Organisms maintain homeostasis, a stable internal environment (e.g., temperature, glucose).
• Organisms share a genetic code.

Specialized Plant Cells

• Plants exchange gases (CO2, O2, H2O) through tiny openings called stomata.

Chemical Energy and ATP

• ATP (adenosine triphosphate) is the base energy source for all cells.
• ATP comprises adenine, ribose, and three phosphate groups.

Cellular Respiration and Photosynthesis

• Cellular Respiration: Breaks down glucose to produce ATP.
  • Substages: glycolysis, Krebs cycle, electron transport chain.
  • Locations: cytoplasm, mitochondrial matrix, mitochondrial membrane.
  • Raw materials: glucose, oxygen
  • Waste products: water, carbon dioxide, oxygen.
  • Major products: ATP, water
• Photosynthesis: Converts light energy into chemical energy.
  • Substages: light-dependent, light-independent (Calvin cycle).
  • Locations: thylakoids, stroma
  • Raw materials: water, carbon dioxide, light.
  • Waste products: oxygen.
  • Major products: glucose, ATP.

Photosynthesis Experiments

• Van Helmont: concluded plant mass gain comes from water.
• Priestley: discovered plants release oxygen.
• Jan Ingenhousz: found light is needed for plant oxygen production.

Definitions

• Homeostasis: maintaining a stable internal environment.
• Autotrophs: organisms that make their own food (e.g., plants).
• Heterotrophs: organisms that eat other organisms (e.g., animals).
• Cell Specialization: different cells perform specific tasks in an organism.
• Cell Culture: growing cells outside their natural environment.
• Cell Fractionation: separating cell parts using a centrifuge.
• Intraspecific competition: competition within the same species.
• Interspecific competition: competition between different species.
• Predation: one organism capturing and consuming another.
• Symbiosis: two species living closely together.
• Mutualism: both species benefit from the relationship.
• Commensalism: one species benefits, the other is unaffected.
• Parasitism: one species benefits, the other is harmed.
• Cell wall: rigid outer layer (plants only).
• Cell membrane (plasma membrane): double layer of lipids and proteins surrounding the cell.
• Prokaryotes: cells lacking a nucleus (e.g., bacteria).
• Eukaryotes: cells with a nucleus (e.g., animals, plants).
• Diffusion: movement of particles from high to low concentration.
• Osmosis: movement of water across a selectively permeable membrane.
• Hypertonic: higher solute concentration.
• Hypotonic: lower solute concentration.
• Isotonic: equal solute concentration.
• Lactic Fermentation: metabolic process converting glucose to energy under anaerobic conditions.

Unit 1B: Classification and Viruses

• Classification System: grouping species into categories (Kingdom, Phylum, Class, Order, Family, Genus, Species).

• Binomial Nomenclature: two-part scientific name for each species (italicized).

• Traditional Classification: based on structure and characteristics.

• Cladogram: diagram showing evolutionary relationships.

• Monera: former kingdom now divided into Eubacteria and Archaebacteria.

• Gram staining: distinguishes two types of bacterial cell walls.

• Decomposers: organisms that break down dead matter.

• Virus Structure: composed of nucleic acid (DNA or RNA) and a protein coat (capsid).

• Asexual Reproduction: reproduction without a partner.

• Sexual Reproduction: reproduction with another organism.

• Bacteriophage: viruses that infect and reproduce in bacteria.

• Angiosperms: flowering plants with seeds enclosed in a structure.

• Monocot: one seed leaf

• Dicot: two seed leaves

• Fruit: ripened ovary containing seeds.

• Seed dispersal methods: wind, animals.

• Tropism: plant response to a stimulus.

  • Positive tropism: growth toward the stimulus.
  • Negative tropism: growth away from the stimulus.

• Gravitropism: response to gravity

• Dormancy: period of suspended growth and development.

• Positive immunity: introduction of foreign antibodies that are only temporary and will be fought by the body.

• Antibody: protein that recognizes and binds to specific antigens

• Antigen: substance that triggers an immune response.

• Virus particle: composed of nucleic acid and protein components.

Unit 2: Genetics

• Genotype: organism's genetic makeup.
• Phenotype: organism's physical traits.
• True-breeding parent: self-pollinating plant that produces offspring identical to itself.
• Offspring: product of sexual or asexual reproduction.
• Parental Generation (P): initial pair of plants.
• Offspring Generation (F1): first generation offspring.
• Mendel's Study: focused on inheritance patterns (flower color, seed shape).
• Mendel's Conclusions:
  • Traits passed from generation to generation through factors (genes).
  • Different forms of a gene are alleles.
• Principle of dominance: some alleles are dominant, others recessive.
• Punnett square: predicting genetic combinations from a cross.
• Codominance: both alleles are equally expressed.
• Incomplete dominance: blended expression of alleles.
• Dominant allele: allele whose effect masks the recessive allele.
• Recessive allele: allele whose effect is masked by a dominant allele.
• Thomas Hunt Morgan's Findings: genes are located on chromosomes.
• Nobel Prize: awarded to Morgan in 1933.
• Diploid (2N): two sets of chromosomes.
• Haploid (n): one set of chromosomes.
• Crossover: exchange of genetic material between homologous chromosomes in meiosis.
• Independent assortment: random distribution of alleles during gamete formation.
• Mitosis: cell division that produces identical cells.
• Meiosis: cell division that produces gametes (sex cells).
• Linked genes: genes located close together on the same chromosome.
• Griffith's findings: bacteria can transfer genetic information (transformation).
• Transcription: DNA is copied into RNA for protein synthesis.
• Codons: three-base sequences in mRNA that code for amino acids.
• Gene mutation: permanent alteration in DNA.
• Lac repressor: protein that regulates lactose metabolism genes.
• Hox genes: control embryonic development.
• Selective breeding: choosing organisms with desired traits for reproduction.
• Genetic engineering: modifying genes using technology.
• Hybridization: breeding dissimilar organisms.
• Inbreeding: breeding similar organisms.
• Polyploid: possessing more than two complete sets of chromosomes.
• DNA gel electrophoresis: separating DNA fragments by size.
• DNA cloning: creating many copies of a gene.
• Ribosomal DNA: crucial for protein synthesis.
• Genetic marker: sequence of DNA to track genetics.
• Pedigree: diagram of family relationships.