Biology Basics

Branches of Biology

• Botany: study of plants and plant-like organisms
• Zoology: study of animals and animal-like organisms
• Microbiology: study of microorganisms such as bacteria and viruses
• Ecology: study of interactions between organisms and their environment
• Biochemistry: study of chemical processes within living organisms
• Molecular Biology: study of biological molecules and their interactions
• Genetics: study of heredity and variation
• Evolutionary Biology: study of the evolution of living organisms

Cell Biology

• Cell: basic structural and functional unit of life
• Cell membrane: semipermeable membrane surrounding the cell
• Cytoplasm: jelly-like substance inside the cell membrane
• Nucleus: control center of the cell where DNA is stored
• Mitochondria: site of cellular respiration
• Ribosomes: site of protein synthesis

Genetics

• DNA (Deoxyribonucleic acid): molecule containing genetic information
• Genes: units of heredity that determine traits
• Chromosomes: thread-like structures made up of DNA and proteins
• Genotype: genetic makeup of an individual
• Phenotype: physical and behavioral traits of an individual
• Dominant and recessive alleles: different forms of a gene that determine traits

Evolution

• Charles Darwin: proposed the theory of evolution through natural selection
• Natural selection: process by which organisms that are better adapted to their environment are more likely to survive and reproduce
• Speciation: process by which a new species emerges
• Fossil record: chronological record of the history of life on Earth
• Homologous structures: structures that are similar in different species due to common ancestry