Sex & Reproduction

Question 1

Asexual

Question 2

Sexual reproduction

Question 3

Clone

Question 4

Parthenogenesis

Question 5

Apomixis

Question 6

Hermaphrodite

Question 7

Explain the roles of asexual and sexual reproduction in Daphnia in relation to environmental conditions

Answer 7

The daphnia water flea is asexual in the summer because of good conditions but sexual in poorer conditions

Question 8

What are the benefits of sexual reproduction?

Answer 8

Sex is a driver of evolution

Question 9

What are the costs of sexual reproduction ?

Answer 9

It is prone to failure
It is relatively inefficient when compared to asexual reproduction
Need a mate (a successful one)
Infertility issues

Question 10

What are the benefits of asexual reproduction?

Answer 10

Simple
Less likely to fail
Might be more advantageous at the time

Question 11

What are the costs of asexual reproduction?

Question 12

What is fission? (asexual reproduction)

Answer 12

Division into two equally-sized offspring e.g. sea anemone

Question 13

What is budding? (Asexual reproduction )

Answer 13

Unequal division into smaller offspring e.g. Hydra (relative of jellyfish)

Question 14

What is fragmentation? (Asexual reproduction)

Answer 14

The parent breaks into many new individuals e.g. Kalanchoe (plant)

Question 15

What is phylogeny?

Answer 15

“Evolutionary descent with reflected levels of genetic similarity because of shared evolutionary history”

Question 16

What is the R-number?

Answer 16

The reproduction number!
E.g. if r = 2, the population doubles per generation

Question 17

Commercial bananas are genetically identical to each other, what does this mean for them?

Answer 17

They can’t evolve quickly

Question 18

Pathogens can adapt and evolve quite quickly, why is this?

Answer 18

Short generation times
Large numbers of progeny
Vast. Numbers offers many new opportunities for new mutations

Question 19

What would it mean if all humans were genetically the same, how easy would it be to catch diseases and viruses?
Why does sex help?

Answer 19

If one person was susceptible to the disease everyone else would be too!
Sex means that everyone isn’t identical, if we were to become asexual then this would be a problem.

Question 20

What is the Red Queen Hypothesis?

Answer 20

Must keep running to stand still

A species must continue evolving as their predators are evolving

Question 21

Polyspermy meaning?

Question 22

Totipotent

Answer 22

Cells that have potential to make all the cell types of an organism!

Question 23

What does it mean if a cell is terminally differentiated?

Answer 23

A fixed single cell type

Question 24

What are the main steps of fertilisation, how is polyspermy avoided?

Question 25

What (simply) is morphogenesis?

Answer 25

The generation of shape, pattern and form

Question 26

What is meant by monoblastic, (radical) diploblastic and (bilateral) tripoblastic?

Answer 26

Monoblastic organisms have no symmetry in their structure.

Radical diploblastic - radially symmetrical

Bilateral tripoblastic - three symmetry lines (have an anterior end and a posterior end)

Question 27

What does it mean if we have an anterior and posterior end?

Answer 27

Food goes in one hole and waste comes out another.