reproductive isolation and evolution in present times Flashcards
What is reproductive isolation?
A mechanism that prevents different species from mating and producing fertile offspring, even without geographic separation.
How does breeding at different times prevent interbreeding?
Species that reproduce or flower at different times cannot interbreed.
What is species-specific courtship behaviour?
Unique signals or behaviors (e.g. songs, dances, pheromones) that attract only members of the same species for mating.
How do plants prevent cross-pollination through pollinators?
By adapting to specific pollinators using flower shape, color, scent, timing, and reward type.
Why can cross-species hybrids not reproduce?
Hybrid offspring (like mules) are usually infertile, preventing gene flow between species.
Why is evolution in bacteria and viruses easier to observe?
Because they reproduce rapidly and mutate often, allowing faster evolutionary changes.
What causes some TB bacteria to be antibiotic-resistant?
Natural variation and mutations lead to some bacteria surviving antibiotics and passing on resistance.
Why is it dangerous to not finish a course of antibiotics for TB?
Incomplete treatment allows resistant bacteria to survive and multiply, making future infections harder to treat.
What is multidrug-resistant TB and why is it concerning?
It’s a form of TB resistant to several antibiotics, requiring aggressive treatment and often leading to poor outcomes.
