Patterns/Mechanisms of Evolution

Question 1

Populations

Answer 1

groups of individuals that are of the same species

Question 2

Fitness

Answer 2

an organism ability to survive and reproduce

Question 3

Adaptation

Answer 3

trait that increases fitness

Question 4

Mutations

Answer 4

random changes in DNA; seldom increases fitness

Question 5

Natural Selection

Answer 5

the difference in reproduction of genes in a population because of the traits that those genes make

Question 6

Evolution

Answer 6

the change of a populations genetic composition over time

Question 7

Gene Pool

Answer 7

all the alleles of a gene in a population

Question 8

What are the five major mechanisms of evolution?

Answer 8

natural selection, mutation, genetic drift, non-random mating, and gene flow

Question 9

Natural selection is….

Answer 9

function driven and non-random reproduction of traits

Question 10

Genetic Drift

Answer 10

the result of random fluctuations in the allele frequency of a population; can greatly affect small populations; this can be due to bottleneck affect (a disaster happening and randomly taking out individuals) or just fluctuations from generation to generation

Question 11

Nonrandom Mating

Answer 11

when mates are chosen by a specific phenotype or characteristic

Question 12

Gene Flow

Answer 12

refers to the emigration and immigration of individuals between populations; basically migration

Question 13

Requirements for HWE

Answer 13

no natural selection, no mutations, no gene flow, no genetic drift (infinitely large population), and only random mating

Question 14

p

Answer 14

the allele frequency of the dominant allele

Question 15

q

Answer 15

allele frequency of the recessive allele

Question 16

p^2

Answer 16

frequency of homozygous dominant individuals

Question 17

2pq

Answer 17

frequency of heterozygous individuals

Question 18

q^2

Answer 18

frequency of homozygous recessive individuals

Question 19

What are the two equations for HWE?

Answer 19

p+q=1 and p^2 + 2pq + q^2=1

Question 20

What is the equation for the chi-squared formula?

Answer 20

x^2 = summation of [(observed - expected)^2 / expected]

Question 21

How to find of degrees of freedom?

Answer 21

subtract one from the number of phenotypes or n-1

Question 22

What number is looked at on a Chi-Squared distribution table?

Answer 22

0.05

Question 23

What does 0.05 mean for Chi-Squared?

Answer 23

the chance that our results are due to random chance are less that 5%

Question 24

What does it mean if the chi-squared value is above the critical value?

Answer 24

the observed is statistically significantly different from the theoretically expected; the population is not in HWE; if chi-squared is bigger than the critical value, something is causing the difference. it is not from random chance

Question 25

What does a large p-value mean?

Answer 25

tells you your datasets are not very different; strong evidence of the null hypothesis being true

Question 26

What does a small p-value mean?

Answer 26

tells you your datasets are different and there is statistical significance; you have evidence to say there is something causing the difference and it is not random; the smaller the p-value the stronger evidence that you should reject the null hypothesis

Question 27

What does a p-value under 0.05 or 5% mean?

Answer 27

potentially good enough to be taken seriously in some way as difference between your datasets

Question 28

What is a t-test?

Answer 28

a statistical test used to compare the means of two groups of data

Question 29

What are p-values?

Answer 29

the probability that you would get your results if your datasets werent actually different; probability that your null hypothesis is true