Exam 1 Flashcards
Biology
scientific study of organisms, living and fossil
Cell
the basic unit of life
Organism
living individuals that consist of more than 1 cell
5 characteristics of living things
- homeostasis
- uses energy
- is organized
- reproduces, grows, and develops
- evolves
Example of homeostasis
maintaining body temperature
levels of organization
atom, molecule, organelle, cells, tissue, organ, organ system, organism
prokaryotes
- bacteria and archaea
- first organisms
- single celled organisms only
- doesn’t have nucleus or organelles
eukaryotes
- formed billions of years after eukaryotes
- can be single or multicellular
- has a nucleus and organelles
most inclusive taxonomic group
domain
least inclusive taxonomic group
species
3 domains
bacteria, archaea, and eukarya
4 kingdoms in domain eukarya
Protista, Fungi, Plantae, and Animalia.
First domain to emerge first
Protista
How old is Earth?
4.6 billion years old
When did the first life form appeared?
4 billion years ago
Photosynthetic organisms?
2.5 billion years ago
First land plants and animals
500 million years ago
What changed in atmosphere to allow organisms to move onto land?
Photosynthesis increased oxygen production, which allowed aerobic capable organisms to flourish due to being able to make energy, and also led to O3 (ozone layer) production, which protected the animals from harmful UV radiation
Unifying principle of biology?
Evolution
Evolution
results in change in the genetic makeup of populations over time
artificial selection
selective breeding of plants and animals to get desirable traits