Evolution

Question 1

What is evolution?

Answer 1

Evolution is the cumulative change in the heritable characteristics of a population. Evolution unifies living organisms as we understand that new species arise from the pre-existing ones

Question 2

When did life begin on earth?

Answer 2

3.7 billion years ago

Question 3

Causes of Genetic Variability

Answer 3

1. Sexual Reproduction - Which Sperm hits which Egg - Meiosis - Independent Assortment 2. Crossing-over - Disjunction 3. Mutation - Environment - Non-corrected mistakes

Question 4

Species

Answer 4

any organism that can reproduce fertile offspring while interbreeding

Question 5

Bacteria

Answer 5

divides by binary fission (asexual reproduction) can evolve through plasmids, which can be transferred between bacteria.

Question 6

Darwin-Wallace theory of evolution

Answer 6

evolution by natural selection

Question 7

Natural Selection

Answer 7

• More offspring are produced than the environment can support - There is a struggle for existence where some individuals survive and some die - Members of a species vary from each other in their characteristics (result of sexual reproduction) - Those individuals with better adaptations for surviving in a particular environment will tend to survive and reproduce more offspring - as the better-adapted individuals pass on their characteristics, these traits tend to accumulate in the population - the characteristics of the species gradually change and the species evolve

Question 8

Lamarck’s theory

Answer 8

is wrong, the influence of environment onto an organism will not be passed down genetically. However, the idea of epigenetics is proving to be correct.

Question 9

Epigenetics

Answer 9

your environment can affect the DNA of your sperm or eggs

Question 10

Examples of evolution in response to environmental change:

Answer 10

1. The development of antibiotic resistance in bacteria 2. The changes in beak size and shape on the finches found in the Galapagos islands 3. Industrial melanism in the peppered moth

Question 11

Geographic Isolation

Answer 11

species is separated from exchanging genetic material with other organisms of the same species

Question 12

Transient Polymorphism

Answer 12

the occurrence of two or more clearly different phenotypes within the same population of a species