Costs And Benefits Of Sexual And Asexual Reproduction

Question 1

What is the definition of sexual reproduction?

Answer 1

The population of new living organisms by combining genetic information from two individuals of different types (sexes)

Question 2

What do the costs of sexual reproduction include?

Answer 2

Males being unable to produce offspring. Only half of each parent’s genome passed onto offspring, disrupting successful parental genomes

Question 3

Why do the benefits of sexual reproduction outweigh the costs?

Answer 3

Due to an increase in genetic variation in the population

Question 4

What does genetic variation provide?

Answer 4

It provides the raw material required for adaptation, giving sexually reproducing organisms a better chance of survival under changing selection pressures

Question 5

How does the red queen hypothesis explain the persistence of sexual reproduction?

Answer 5

The red queen hypothesis postulates that parasite pressure maintains sexual reproduction in the host population by selecting for the ability to produce rare genotypes that are resistant to infection

Question 6

What may co-evolutionary interactions between parasites and hosts may select for?

Answer 6

They may select for sexually reproducing hosts

Question 7

What shows that hosts have better fitness?

Answer 7

The hosts that are able to resist and tolerate parasitism

Question 8

What shows that parasites have a greater fitness?

Answer 8

When they are better able to feed, reproduce and find new hosts

Question 9

What happens to the genetic variability to offspring of the host who reproduce sexually?

Answer 9

The genetic variability in their offspring reduces the chance that they will be susceptible to infection by parasites

Question 9

What is the definition of asexual reproduction?

Answer 9

A type of reproduction by which offspring arise from a single organism and inherit the genes of that parent only; it does not involve the fusion of of gametes

Question 9

What does asexual reproduction allow for colonies?

Answer 9

It allows just one parent to produce daughter cells and establish a colony of virtually unlimited size over time

Question 10

Why can asexual reproduction be a successful reproductive strategy?

Answer 10

Because whole genomes are passed on from parent to offspring

Question 11

Where is maintaining the genome of the parent an advantage?

Answer 11

It is particularly an advantage in very narrow, stable niches or when recolonising disturbed habitats

Question 12

What are some examples of asexual reproduction in eukaryotes?

Answer 12

Vegetative cloning in plants and parthenogenesis in lower plants and animals that lack fertilisation

Question 13

What is parthenogenesis?

Answer 13

It is the reproduction from a female gamete without fertilisation

Question 14

Where is parthenogenesis more common?

Answer 14

In cooler climates, where disadvantageous to parasites, or regions of low parasite density or diversity

Question 15

What is the positive of asexual reproduction?

Answer 15

Offspring can be produced more often and in larger numbers

Question 16

How does asexual reproduction effect populations?

Answer 16

Asexually reproducing populations are not able to adapt easily to changes in their environments, but mutations can occur that provide some degree of variation and enable some natural selection and evolution to occur

Question 17

What is horizontal gene transfer?

Answer 17

Organisms that reproduce principally by asexual reproduction also often have mechanisms for horizontal gene transfer between individuals to increase variation, for example the plasmids of bacteria and yeast

Question 18

What does prokaryotes exchanging genetic material horizontally result in?

Answer 18

Faster evolutionary change than in organisms that only use vertical transfer