Biology Introduction: Characteristics of Life

Study Notes

Biology is the science of living things, an unified science that combines biology, chemistry, and physics.

Cellular Composition: living things are made up of at least one cell.
Types of Cellular Composition:
Unicellular: one cell, only visible using a microscope (e.g., bacteria, amoeba, paramecium).
Multicellular: more than one cell (e.g., plants, fungi, animals).
Growth: increase in cell size or cell number.
Reproduction:
Asexual: cell division (mitosis), one cell becomes two (e.g., bacteria).
Sexual: union of sex cells (sperm and egg cells), seen in plants and animals.
Movement:
Place to place: bear running, birds flying.
External part: phototropism, plants orient leaves toward the sun.
Internal part: cytoplasmic streaming.
Adaptation:
Changing to meet the needs of the environment (e.g., bird migration, human body temperature).
Metabolism: set of chemical reactions that convert "food" into energy (e.g., glycolysis, Krebs cycle).
Specific Organization: certain parts do specific jobs (e.g., heart, nucleus, chloroplasts).
Homeostasis: maintaining the same state (e.g., water balance inside and outside of cell, human body temperature).
Responsiveness: reactions to various stimuli (e.g., light, heat, pH, vibration).

Zoology: study of animals.
Ichthyology: study of fish (fish are indicator species, alerting humans to potential environmental problems).
Mammalogy: study of mammals (e.g., NASA).
Ornithology: study of birds.
Botany: study of plants (e.g., food production, medicines).
Microbiology: study of small life (e.g., medicines, bioterrorism).
Anatomy: study of an organism's parts.
Physiology: study of how organism's parts work (e.g., health professions, veterinarians).
Entomology: study of insects (e.g., West Nile virus, Yellow Fever - carried by mosquitoes).
Genetics: study of hereditary and genetic material (e.g., DNA/RNA, chromosomes, genes).
Ecology: study of all life in a particular area, the relationships between those life forms and the environment (e.g., AMD, overpopulation, ozone depletion/greenhouse effect, rainforest destruction).
Cell Biology: study of cells.