The genetic changes in a population over generations.
A process where some individuals of a population have genetically based traits that cause them to better survive and produce more offspring than other individuals.
A basic unit of living matter separated from its environment by a plasma membrane. Cells are the fundamental structural untis of life.
Lacks a nucleus and other mebranne-enclosed organelles. Found only in bacteria and archaea.
Has a membrane-enclosed nucleus and other membrane-enclosed organelles. All organisms except bacteria and archaea are composed of eukaryotic cells.
single-celled eukaryotic organisms, eg amoeba and protozoans
- Movement: eg locomotion of turning leaves towards the sun.
- Respiration: converting food into stored chemical energy.
- Sensitivity to stimuli: any action that occurs as a result of a change in the local environment.
- Growth: by assimilating materials from food.
- Reproduction: sexually (by combination of two gametes), or asexually (eg tapeworm/budding, plants/runners)
- Excretion: mainly CO2.
- Nutrition: utilise energy.
- 1920s. First put forward the hypothesis that conditions on early Earth could have generated organic molecules.
- Note: Miller later confirmed this hypothesis (1953).
- Proved that complex organic molecules can form spontaneously under conditions that probably existed on the early earth.
- Demonstrated the kinds of molecules that could have been produced on the early earth.
Sort the following from oldest to most recent:
a) prokaryotic cells
b) eukaryotic cells
a, d, b, c (check)
What were sources of energy on the early Earth?
- UV radiation
- volcanic eruptions