Biology Fundamentals

Ecology

• Study of the interactions between organisms and their environment
• Examines the relationships between living organisms and their physical surroundings
• Key concepts:
  • Ecosystem: community of living and non-living components interacting in an environment
  • Population: group of individuals of the same species living in a specific area
  • Community: group of different species living in a specific area
  • Biodiversity: variety of species, genes, and ecosystems in an environment
  • Ecological niches: specific roles or positions occupied by species in an ecosystem
• Levels of ecological study:
  1. Organismal ecology: focuses on individual organisms
  2. Population ecology: focuses on groups of individuals of the same species
  3. Community ecology: focuses on groups of different species
  4. Ecosystem ecology: focuses on the interactions between living and non-living components
  5. Landscape ecology: focuses on the interactions between different ecosystems

Genetics

• Study of heredity and variation in organisms
• Examines the transmission of traits from one generation to the next
• Key concepts:
  • DNA (deoxyribonucleic acid): molecule containing genetic information
  • Genes: units of heredity that carry information from one generation to the next
  • Alleles: different forms of a gene
  • Genotype: genetic makeup of an individual
  • Phenotype: physical characteristics of an individual
• Mendelian inheritance:
  • Laws of segregation and independent assortment
  • Dominant and recessive alleles
  • Punnett squares: graphical representation of possible genotypes and phenotypes
• Molecular genetics:
  • DNA replication and transcription
  • Gene expression and regulation

Cell Biology

• Study of the structure, function, and behavior of cells
• Examines the basic units of life
• Key concepts:
  • Cell structure:
    • Plasma membrane: outer layer of the cell
    • Cytoplasm: region between the plasma membrane and the nucleus
    • Nucleus: contains genetic material
    • Organelles: specialized structures within the cell
  • Cell function:
    • Metabolism: energy production and consumption
    • Signaling: communication between cells
    • Cell division: process of cell growth and reproduction
  • Cell signaling:
    • Hormone signaling
    • Neurotransmission
    • Cell-cell signaling

Evolution

• Study of the changes in species over time
• Examines the diversity of life on Earth
• Key concepts:
  • Mechanisms of evolution:
    • Mutation: changes in DNA sequence
    • Gene flow: movement of genes between populations
    • Genetic drift: random changes in gene frequency
    • Natural selection: survival and reproduction of individuals with favorable traits
  • Evidence for evolution:
    • Fossil record: chronological record of ancient life forms
    • Comparative anatomy: similarities and differences in body structure
    • Molecular biology: similarities in DNA and protein sequences
  • Evolutionary processes:
    • Speciation: formation of new species
    • Adaptation: development of traits that enhance survival and reproduction
    • Co-evolution: reciprocal adaptation between species