Buffer
Tags
eco
cegep/3
Word count
311 words
Reading time
2 minutes
- quiz sep 16
- test sep 30
- lab test nov 20
- 4 units
- 1 evolution
- 1.6 biodiversity
- 2 ecology
- 3 human factor
2025-08-19
- Early Earth
- Reducing atmosphere (no oxygen)
- Electrically charged
- Hot
- CO2, H2, N2, water vapor
- Protocell
- Origin of first cells
- Packaged into vesicles surrounded by membrane
- Uses RNA because more catalytic than DNA, e.g. ribozymes
- Reproduces by binary fission
- Maintains homeostasis
- First cell
- Prokaryote
- Needs:
- Amino acids, sugars, nucleotides
- Water
- No oxygen
- Energy
- Autotrophy
- Dependency on light energy and inorganic molecules
- Uses photosynthesis
- Includes consumers and decomposers
- Heterotrophy
- Dependency on other organisms for their energy and nutrients
- Mostly aerobic
- Aerobic
- Requires O2
- Anaerobic
- Does not require O2
- Facultative
- Can live in both aerobic and anaerobic conditions
- Obligate
- Can only live in either aerobic or anaerobic conditions
2025-08-21
- Formation of ozone layer
- UV forms O3 from O2 in the upper atmosphere
- O3 absorbs UV
- Decreases mutagenesis
- Adaptive radiation
- Rapid diversification
- Historical causes:
- Multicellularity
- Colonization of land
- Mass extinctions, e.g. dinosaur extinction enabled radiation of mammals
- Continental drift
- Mass extinction
- Extinction of >75% of species within 1-10 million years
- Natural extinction rate: 1 in a million species becomes extinct per year
- Current extinction rate: 100-1000 times higher
similar species
[!abstract]+ morphological species
Organisms with similar body shapes, sizes and other structural features
[!abstract]+ biological species
Organisms that interbreed and produce fertile offsprings
[!abstract]+ ecological species
Organisms that share the same ecological niche
[!abstract]+ phylogenetic species
Organisms that share common ancestry based on DNA sequences
Ajitani Hifumi