Evolution Today Flashcards
What do you need for Evolution to work?
Variation must occur – environment select individuals whose variations give an advantage. Advantageous individuals survive and reproduce – pass on advantageous characteristics (inherit). Next generation adapted to their environment.
What type of variation is passed on?
Genetic variation passed on, environmental variation not passed on.
How may a new species evolve?
A group of individuals may evolve into a new species – this may occur if: a population of te species migrates to a new environment, an environmental change, only effects some of the population, reproductive barriers preventing interbreeding.
What is Selection Pressure?
Selection pressure is an external pressure that drives evolution in a particular direction.
How has resistance to insecticides developed?
Resistance to insecticides has developed in many ways: the insects may be able to break down the insecticide (using enzymes), the target receptors protein on the cell membrane may be modified. Mosquitos resistant to DDT and Pyrethroids by evolving receptors.
What does prescribing multiple drugs do?
Prescribing multiple drugs decreases likelihood of a strain surviving. MRSA – Methicillin-resistant Staphylococcus aureus.
