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Flashcards in Evolution Deck (19)
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1
Q

define evolution

A

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

2
Q

what are the three processes that could influence evolution

A

genetic drift, natural selection and sexual selection

3
Q

what is a novel allele

A

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

4
Q

what are the two things mutation can give rise to

A

new alleles, new combinations of alleles

5
Q

is genetic drift random or non random

A

random

6
Q

how does natural selection work

A

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

7
Q

how does sexual selection differ from natural selection

A

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

8
Q

in what populations is genetic drift more noticeable

A

smaller populations

9
Q

what is absolute fitness

A

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

10
Q

what is the relative fitness

A

compares the absolute fitness to the fitness you are calculating

11
Q

what five factors have an influence on natural selection

A

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

12
Q

what are the three types of hgt

A

transformation, conjunction and transduction

13
Q

how do shorter generation times influence the rate of evolution

A

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

14
Q

what are the two ways warmer climates can affect evolution rate

A
  • 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
15
Q

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

A

bacteria

16
Q

where is coevolution frequently seen

A

in pairs of species that interact frequently

17
Q

describe how the red Queen hypothesis is often connected with coevolution

A

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

18
Q

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

A

selection pressure

19
Q

give an example of a co-evolved pair of organisms

A

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