lecture 2 - variance and natural selection

Question 1

three domains of life

Answer 1

bacteria, archaea, eukarya

Question 2

bacteria

Answer 2

prokaryotes

Question 3

archaea

Answer 3

bacteria that live in extreme environments

Question 4

eukarya and 4 main kingdoms (more complicated as it goes down)

Answer 4

kingdom protista (unicellular protists)
kingdom plantae*
kingdom fungi*
kingdom animalia* (ex: humans)
*multicellular: more complicated as you go down the list

Question 5

darwin-wallace theory of evolution

Answer 5

4 basic concepts:

• there is variation in the individuals of a population (not all organisms are the same)
• variations are inherited (genetics)
• members of a pop. will always produce more offspring than environment can support (fight for survival)
• best fitness will leave more offspring (will survive the longest to reproduce)

Question 6

natural selection

Answer 6

“survival of the fittest” - there is variability in nature. some traits will be more advantageous than others. overtime, natural selection will favour certain traits. changes in environment or species moving to new environment, they will adapt.

Question 7

variance

Answer 7

genetic variation within a population which can be inherited

Question 8

competition

Answer 8

overproduction of offspring leads to competition for survival

Question 9

adaptations

Answer 9

individuals with beneficial adaptations are more likely to survive to pass on their genes

Question 10

selection

Answer 10

over many generations, there is a change in allele frequency (evolution)

Question 11

3 primary sources of genetic variation:

Answer 11

1) mutations (changes in DNA of an organism)
2) gene flow (movement of genes from one population to another)
3) meiosis (the process of reshuffling genes to give to next generation)

Question 12

true or false? if the variance for a given trait is too low in a population, then trait is less likely to evolve

Answer 12

true

Question 13

true or false? without genetic variation, some basic mechanisms of evolution and natural selection can’t operate

Answer 13

true - you want to outbreed, not inbreed (why incest is taboo)