Evolution

Question 1

define evolution

Answer 1

gradual change over many generations in the proportion of individuals in a population that differ in one or more inherited trait

Question 2

what are the three processes that could influence evolution

Answer 2

genetic drift, natural selection and sexual selection

Question 3

what is a novel allele

Answer 3

an allele that codes for a different amino acid in a polypeptide due to a mutation

Question 4

what are the two things mutation can give rise to

Answer 4

new alleles, new combinations of alleles

Question 5

is genetic drift random or non random

Answer 5

random

Question 6

how does natural selection work

Answer 6

alleles that are beneficial increase the organisms survival chance and so those organisms have a greater chance of surviving, increasing the chance of them passing on their genes

Question 7

how does sexual selection differ from natural selection

Answer 7

sexual selection works on genes that increase the chance of reproduction whilst natural selection works on genes that increase the chance of survival

Question 8

in what populations is genetic drift more noticeable

Answer 8

smaller populations

Question 9

what is absolute fitness

Answer 9

ratio of frequencies of a particular genotype in one generation compared to a previous generation

Question 10

what is the relative fitness

Answer 10

compares the absolute fitness to the fitness you are calculating

Question 11

what five factors have an influence on natural selection

Answer 11

high selection pressures, shorter generation times, warmer climates, horizontal gene transfer , sexual reproduction

Question 12

what are the three types of hgt

Answer 12

transformation, conjunction and transduction

Question 13

how do shorter generation times influence the rate of evolution

Answer 13

organisms who go through more generations in a given time while have a greater chance of mutation as increased DNA replication so that will provide more raw material for evolution to work on

Question 14

what are the two ways warmer climates can affect evolution rate

Answer 14

• increase weather, enzymes work faster, divide more frequently or animal may hibernate and have a lower metabolic rate so will produce less cells and have a lessened chance of error

Question 15

give an example of an organism whos evolution rate is influenced by their short generation time

Answer 15

bacteria

Question 16

where is coevolution frequently seen

Answer 16

in pairs of species that interact frequently

Question 17

describe how the red Queen hypothesis is often connected with coevolution

Answer 17

both species have to keep running to stay still, like the red Queen and Alice, analogy from through the looking glass, often seen in nature in the evolutionary arms race, especially in parasites and hosts

Question 18

what does the changes in the trait of one species act as to another species it closely interacts with

Answer 18

selection pressure

Question 19

give an example of a co-evolved pair of organisms

Answer 19

parasites and hosts - find new ways to tolerate parasites/feed on new hosts and reproduce. plants and pollinators - new ways to get nectar and transfer nectar