BIO chap 17 Questions

Question 1

What is variation in Natural populations?

Answer 1

We are trying to understand what level is coded for genetic variation and which is coded for environmental variation

Question 2

What is Phenotypic variation?

Answer 2

Heritable variation in appearance/function (behaviour)

Question 3

What is Phenotypic plasticity?

Answer 3

When two individuals have the exact same genotype but are placed in different environments which leads them to having different phenotypic traits because they’re expressed differently based on their enviornement.

Question 4

What is Quantitative variation?

Answer 4

When individuals differ in small incremental ways. On a frequency distribution. If you notice a low broad curve that indicates their is a lot of variation among individuals but if you notice a high peak curve, that indicates there is very few variation among individuals

Question 5

What is Qualitative variation?

Answer 5

Characteristics with discrete states (two diff things like orange and blue)

Question 6

What is polymorphism?

Answer 6

Individuals with discrete characteristics but within the same species like birds with different colours (example of qualitative)

Question 7

Are genotypes and phenotypes always correlated?

Answer 7

No

Phenotypic variation is due to genetics, environment or the interaction of the two

Question 8

Give an example on how genotypes and phenotypes are not always correlated

Answer 8

You have the two flower seeds with the same genotype. One grows to be blue and the other grows to be pink. This is because they grew on different environments. Blue grew on acidic soil and pink grew on Alkaline soil

Question 9

What is standing genetic variation?

Answer 9

Variation that exists within a population that may not be selected on now, but later if the environment changes, it can be used

Question 10

What is a genetic structure?

Answer 10

When a population gets isolated and start mating with one another which in other terms is inbred. And this made the population really similar genetically. Everyone had the same kind of alleles

Question 11

What is the Hardy-Weinberg principle?

Answer 11

When a population is not evolving. It’ll be considered in HW if it is not.

Question 12

What is genetic variation?

Answer 12

When individuals posses different versions of the same genes. Can happen through production of new alleles or rearrangement of existing alleles leading to new recombination’s

Question 13

What is a locus?

Answer 13

Location of a gene on a chromosome

Question 14

What is a gene pool?

Answer 14

All alleles at all loci in a population

Question 15

What is SNPs?

Answer 15

Difference in amino acid sequences which indicates difference amongst individuals. Normally a single nucleotide polymorphism

Question 16

What is genotype frequency?

Answer 16

Percentage of individuals possessing genotype

Question 17

What is allele frequency?

Answer 17

Calculated from genotype in diploid organisms

P & Q: two different alleles at a locus

Question 18

What happens if conditions are met in HW?

Answer 18

Microevolution does not occur

Question 19

What happens if conditions are NOT met in HW?

Answer 19

Microevolution does occur

Question 20

What are some conditions that can prove evolution is not happening?

Answer 20

• No mutations occurring in the population
• Population is closed to migration
• All genotypes free of selection
• Population infinite in size
• Random mating with respect to genotype

Question 21

What are the effects of blind luck when it comes to picking random gametes from a pool?

Answer 21

Each time you pull different gametes from a gamete pool, you will get a different ratio of alleles. This will cause a population to evolve in an unpredictable manner.

Question 22

What does it mean when you have the same allele initial frequency and same allele final frequency?

Answer 22

That means evolution is not happening within a population and the population is in HW

Question 23

What if genetic drift?

Answer 23

Subtle change in frequency because of random chance.

Ex. the idea of picking random gametes from a gamete pool resulting in a slightly changed final allele frequency

Question 24

What is the HW equilibrium?

Answer 24

Frequency of homozygote dominant genotype (p^2) + Frequency of heterozygote genotype (2pq) + Frequency of homozygote recessive genotype (q^2) = 1

Question 25

What are HW’s 5 assumptions?

Answer 25

1. No mutation (no new alleles have been created which means a lack in different allele
2. No NS (all individuals survive at equal rates and individuals contribute equal number of gametes in the gene pool)
3. No migration (individuals do not move in or out of population, no gene flow)
4. No chance events ( idea of passing alleles onto the next generation , blind luck plays no role)
5. Individuals choose their mates at random (gametes find each other randomly)

Question 26

What happens if “no mutation” is violated?

Answer 26

Allele frequency will change within a population which means evolution is happening

Question 27

What happens if “no NS” is violated?

Answer 27

That means that some individuals with some genotypes with survive over others and reproduce which leads to a change in allele frequency

Question 28

What happens if “no migration” is violated?

Answer 28

Individuals will be carrying high frequency alleles out of the population which will allow allele frequencies to change and also allow gene flow

Question 29

What happens if “ no chance events” is violated?

Answer 29

Genetic drift, allele frequencies will change

Question 30

What happens if “individuals choose their mates at random” is violated?

Answer 30

Individuals prefer to mate with individuals with the same genotypes. This can cause loss of fitness because inbreeding increases homozygotes like AA and aa and decreases heterozygotes like Aa which is not good for fitness.

Question 31

What are the four agents of Microevolution? (Drives population OUT of HW)

Answer 31

1. Gene flow
2. Genetic drift
3. Mutations
4. Natural Selection