Chapter 2 - Genetics & Processes of Evolution

Question 1

What are 3 different definitions of Evolution?

Answer 1

1. “Descent with modification”
2. A change in the genetic structure of a population from generation to generation
3. A change in the frequency of genes over time

Question 2

What is Adaptation?

Answer 2

Adaptation - an anatomical, physiological, or behavioural response to the environment.

Question 3

Define “Monogenic”

Answer 3

coded for by one gene (one set of alleles) - pea wrinkled or smooth

Question 4

Define “Polygenic”

Answer 4

coded for by more than one gene (more than one set of alleles) - hair colour, skin colour

Question 5

Why can “blending” of features be seen in some physical characteristics, even though particulate inheritance is how genes are passed down?

Answer 5

The complex interaction of multiple genes can cause the appearance of blending - also, some alleles are CODOMINANT, which means neither trait is suppressed and therefore both traits can be visible

Question 6

Define “genotype” Hint - Gene

Answer 6

Genotype: the genetic makeup of an individual.

Question 7

Define “phenotype” Hint - starts with Ph

Answer 7

Phenotype: the observable physical characteristics of an organism.

Question 8

Define “Adaptive Radiation”

Answer 8

Adaptive radiation is the evolution of multiple divergent species from a single, less specialized species (e.g. Darwin’s Finches)`

Question 9

Who was the other guy who released a book on evolution around the same time Darwin did?

Answer 9

Alfred Russel Wallace

Question 10

What are the 8 tenets of natural selection?

Answer 10

1. There is variation in all species
2. Variation is heritable
3. Some variants are better equipped to deal with their environment
4. If left unchecked, every organism will produce more offspring than can survive
5. More offspring with better adapted variants will survive
6. Offspring will have the adaptations of their parents
7. Over time, this will result in a change in population to resemble the better-adapted variants
8. As populations of a species become geographically separated from each other, they adapt to their different environments. Over time these populations may become distinct species.

Question 11

What is the first tenet of natural selection?

Answer 11

1. There is variation in all species

Question 12

What is the second tenet of natural selection?

Answer 12

2. Variation is heritable

Question 13

What is the third tenet of natural selection?

Answer 13

3. Some variants are better equipped to deal with their environment

Question 14

What is the fourth tenet of natural selection?

Answer 14

4. If left unchecked, every organism will produce more offspring than can survive

Question 15

What is the fifth tenet of natural selection?

Answer 15

5. More offspring with better adapted variants will survive

Question 16

What is the sixth tenet of natural selection?

Answer 16

6. Offspring will have the adaptations of their parents

Question 17

What is the seventh tenet of natural selection?

Answer 17

7. Over time, this will result in a change in population to resemble the better-adapted variants

Question 18

What is the eighth tenet of natural selection?

Answer 18

8. As populations of a species become geographically separated from each other, they adapt to their different environments. Over time these populations may become distinct species.

Question 19

Define “Niche”.

Answer 19

Niche: the role of a species in its environment. Adaptive radiation happens when there are open niches.

Question 20

Define “Natural Selection”.

Answer 20

Natural Selection: genetic changes in the frequencies of certain traits in populations due to differential reproductive success between individuals.

Question 21

What are the four fundamentals of evolutionary change produced by natural selection?

Answer 21

1. A trait must be inherited if natural selection is to act on it
2. Natural Selection cannot occur without population variation in inherited characteristics.
3. Fitness is relative to the environment a species inhabits.
4. Natural Selection can only act on traits that affect the well-being of the individual BEFORE they reproduce. For example, Alzheimer’s and cancer cannot be selected for.

Question 22

What is the third fundamental of evolutionary change?

Answer 22

3. Fitness is relative to the environment a species inhabits, or survival of the fittest is in relation to the demands of the environment

Question 23

What is the first fundamental of evolutionary change?

Answer 23

1. A trait must be inherited if natural selection is to act on it

Question 24

What is the second fundamental of evolutionary change?

Answer 24

2. Natural Selection cannot occur without population variation in inherited characteristics.

Question 25

What is the Fourth fundamental of evolutionary change?

Answer 25

4. Natural Selection can only act on traits that affect the well-being of the individual BEFORE they reproduce. For example, Alzheimer's and cancer cannot be selected for.

Question 26

What are the 3 types of Selection in evolution?

Answer 26

``` natural selection (survival of the fittest) artificial selection (dog breeding) sexual selection (selection on features associated with mating, e.g. peacock tail) ```

Question 27

What are the 4 types of Genetic Drift in evolution?

Answer 27

- gamete sampling (changes in genetic material that gets passed to the next generation as a result of RANDOM CHANCE) - fission effect (group of animals is split changing the overall genetic makeup of the group - first step in speciation) - founder effect (group of animals make a new, smaller population, changing the overall genetic makeup of the group) - evolutionary bottleneck (a restriction in genetic variability with a decrease in population size resulting from random factors)

Question 28

What is Mutation?

Answer 28

Mutation (a change in DNA, changes in DNA bases, chromosome number, or structure- the ultimate source of variability)

Question 29

What is Gene Flow?

Answer 29

Gene Flow ( the exchange of genes between populations, making two populations more similar)

Question 30

What are 4 processes that can lead to evolutionary change?

Answer 30

Selection --------------------- natural selection (survival of the fittest) artificial selection (dog breeding) sexual selection (selection on features associated with mating, e.g. peacock tail) Genetic Drift (evolutionary change as a result of RANDOM processes, e.g. flood wipes out all cream-coloured buffalo now there is only brown buffalo) - ---------------------------------- - gamete sampling (changes in genetic material that gets passed to the next generation as a result of RANDOM CHANCE) - fission effect (group of animals is split changing the overall genetic makeup of the group - first step in speciation) - founder effect (group of animals make a new, smaller population, changing the overall genetic makeup of the group) - evolutionary bottleneck (a restriction in genetic variability with a decrease in population size resulting from random factors) Mutation (a change in DNA, changes in DNA bases, chromosome number, or structure- the ultimate source of variability) Gene Flow ( the exchange of genes between populations, making two populations more similar)

Question 31

What are the two types of sexual selection?

Answer 31

Male competition for females (if success in fighting makes the winner more likely to mate, those traits will be passed down) Female choice (males putting effort into their appearance to entice more females to mate with them, thus passing down their traits)

Question 32

Define Microevolution

Answer 32

small changes occurring within species that can be observed within a human lifetime

Question 33

Define Macroevolution

Answer 33

changes produced only after many generations

Question 34

Define "Gene"

Answer 34

a sequence of DNA bases that specifies the order of amino acids in an entire protein, portion of protein, or any functional product.

Question 35

Define "Allele"

Answer 35

Alternate forms of a gene (smooth vs wrinkled)

Question 36

Define "Homozygous"

Answer 36

possessing 2 of the same allele (SS, ss)

Question 37

Define "Heterozygous"

Answer 37

possessing 2 different alleles (Ss)

Question 38

What is the 'Dominant Allele'?

Answer 38

Dominant Allele: the allele that is able to suppress the expression of the other allele -the allele that is expressed in a heterozygote

Question 39

What is the Recessive Allele?

Answer 39

Recessive Allele: The allele that is not expressed in a heterozygote

Question 40

Who described the structure of DNA in 1953 and who did they steal it from?

Answer 40

James Watson and Francis Crick, and they stole it from Rosalind Franklin