Topic 3 -5 Flashcards
(16 cards)
What must occur for a new species to form?
Part of an existing population must become reproductively isolated from another part
What is reproductive isolation?
When two (or more) parts of a population cannot interbreed
Name a type of reproductive isolation caused by physical barriers.
Geographical isolation
What is habitat/ecological isolation?
Populations occupy different habitats in the same area so do not meet to breed
Define seasonal/temporal isolation.
Species exist in the same area but are active for reproduction at different times
What is mechanical isolation?
The reproductive organs no longer fit together
Explain behavioural isolation.
Populations do not respond to each other’s reproductive displays
What is gametic isolation?
Male and female gametes from two populations are incompatible
What can reproductive isolation lead to?
Allopatric and sympatric speciation
What is allopatric speciation?
Formation of a new species when populations are physically or geographically isolated
What can cause a change in allele frequencies in isolated populations?
Natural selection
What is sympatric speciation?
Reproductive isolation of two parts of a population in the same place
True or False: Sympatric speciation requires a physical barrier.
False
Why have certain bacteria become resistant to antibiotics?
Due to high reproductive and mutation rates
What can be done to combat antibiotic resistance?
- Reduce the use of antibiotics in humans and farming
- Use DNA sequencing to identify bacteria
- Develop new types of antibiotics from the natural world
Fill in the blank: Bacteria can develop resistance faster than the ______ can discover and test new medicines.
drug industry
