Biology Review: Ecology, Genetics, Evolution, and More

Ecology

• Study of interactions between organisms and their environment
• Focuses on understanding the distribution and abundance of organisms
• Key concepts:
  • Ecosystem: community of organisms and their physical environment
  • Biodiversity: variety of species, genes, and ecosystems
  • Energy flow: energy transfer between trophic levels
  • Nutrient cycling: recycling of nutrients through ecosystems
• Subfields:
  • Population ecology: study of population dynamics
  • Community ecology: study of species interactions
  • Ecosystem ecology: study of energy flow and nutrient cycling

Genetics

• Study of heredity and variation
• Focuses on understanding the transmission of traits from one generation to the next
• Key concepts:
  • DNA: genetic material that carries information
  • Genes: units of heredity that code for traits
  • Alleles: different forms of a gene
  • Genotype: genetic makeup of an individual
  • Phenotype: physical expression of a genotype
• Mendelian inheritance: principles of inheritance based on Gregor Mendel's work
  • Laws of segregation and independent assortment

Evolution

• Study of the changes in species over time
• Focuses on understanding the diversity of life on Earth
• Key concepts:
  • Natural selection: process by which populations adapt to their environment
  • Speciation: formation of new species
  • Fossil record: chronological record of the history of life on Earth
  • Phylogeny: study of evolutionary relationships between organisms
• Mechanisms of evolution:
  • Mutation: changes in DNA sequence
  • Genetic drift: random changes in gene frequency
  • Gene flow: movement of genes between populations

Cell Biology

• Study of the structure, function, and behavior of cells
• Focuses on understanding the basic units of life
• Key concepts:
  • Cell membrane: semipermeable membrane that surrounds the cell
  • Organelles: specialized structures within cells
  • Cytoskeleton: network of filaments that provides cell shape and support
  • Cell signaling: communication between cells
• Cellular processes:
  • Metabolism: energy conversion and nutrient uptake
  • Cell division: process of cell growth and reproduction
  • Cell death: programmed cell death (apoptosis)

Microbiology

• Study of microorganisms, such as bacteria, viruses, and fungi
• Focuses on understanding the biology and ecology of microorganisms
• Key concepts:
  • Microbial diversity: vast range of microorganisms in different environments
  • Microbial ecology: study of microbial interactions with their environment
  • Microbial evolution: evolution of microorganisms over time
• Microbial processes:
  • Fermentation: energy production in the absence of oxygen
  • Nitrogen cycling: microbial role in nitrogen conversion
  • Pathogenesis: study of microbial disease-causing mechanisms