Cell Division: Reproduction (paper 2)

Question 1

what are the 2 types of reproduction

Answer 1

• sexual
• asexual

Question 2

where does asexual reproduction occur

Answer 2

• bacteria
• some plants
• some animals

Question 3

what are the 5 key things that define asexual reproduction

Answer 3

• involves mitosis / binary fissions** for bacteria
• only 1 parent
• does not involve the fusion of gametes
• does not result in the mixing of genetic information
• produces genetically identical offspring –> clones

Question 4

what is the asexual process called in plants

Answer 4

vegetative reproduction

Question 5

Vegetative reproduction does not produced …………, ………………., ………………

Answer 5

• spores
• pollen
• seeds

Question 6

what are 3 examples of vegetative reproduction

Answer 6

• runners : strawberry plants
• bulbs : daffodils
• tubers : potatoes

Question 7

what are the advantages of asexual reproduction

Answer 7

• faster process (quicker)
• produces lots more offspring
• 1 parent –> no need fore mate –> easier

Question 8

what are the advantages of sexual reproduction

Answer 8

• population resistance to disease / harsh environment
• humans can use it in selective breeding

Question 9

how many parents does sexual reproduction need

Answer 9

2

Question 10

in which organisms does sexual reproduction occur

Answer 10

• animals
• plants

Question 11

what are the 5 key things that define sexual reproduction

Answer 11

• needs 2 parents
• requires the fusions of male and female gametes –> process of fertilisation must occur
• mixing of genetic information –> leads to variety in offspring
• offspring are genetically different from both of their parents

Question 12

what are the gametes call in male and females

Answer 12

• Male: Sperm (in animals), pollen (plants**
• Female: Ova

Question 13

the formation of gametes invole what type of cell division

Answer 13

meiosis

Question 14

how many chromosome does a gamete have and what is it called

Answer 14

23 - haploid

Question 15

describe the stages of fertilisation

Answer 15

1. ovum + sperm fuse during fertilisation
2. results in a single cell called a zygote –> has full set of chromosomes , diploid cell
3. zygote will develop into an embryo by mitosis
4. as embryo develops : cells differentiate to form different types of cells + tissues

Question 16

offspring produced in sexual reproduction have a greater variation than offspring produced by asexual reproduction, why?

Answer 16

process of fertilisation mean that zygote receives half of its genetic information from its mother, half from its father –> embryo inherits characteristics from both parents

Question 17

where in the body do cell divide by meiosis

Answer 17

reproductive organs to form gametes

Question 18

reproductive organs include:

Answer 18

• testes and ovaries in animals
• anthers and ovaries in flowering plants

Question 19

describe the stages of meisosis

Answer 19

• copies of the genetic information are made
• the cell divides twice to form 4 gametes, each with a single set of chromosomes

Question 20

Advantages of sexual reproduction

Answer 20

• produces genetically varied offspring : if environment changes variation gives a survival advantage by natural
  selection
• natural selection can be speeded up by humans in selective breeding to
  increase food production.

Question 21

Advantages of asexual reproduction:

Answer 21

• only one parent needed
• more time and energy efficient as do not need to find a mate
• faster than sexual reproduction
• many genetically identical offspring can be produced when conditions are favourable

Question 22

what organisms use both sexual and asexual reproduction

Answer 22

• malaria parasite
• fungi
• Plants:
  
  • strawberry plant
  • daffodils, onions
  • potatoes

Question 23

how does malaria parasite carry out sexual reproduction and asexual reproduction

Answer 23

• reproduces sexually when it is inside the mosquito (acts as vector)
• reproduces asexually when it is inside human host liver cells

Question 24

how does fungi carry out sexual reproduction and asexual reproduction

Answer 24

• reproduce spores sexually - these are genetically varied
• also reproduce spores asexually - genetically identical to parent

Question 25

how does the strawberry plant carry out sexual reproduction and asexual reproduction

Answer 25

Sexual:
- produce gametes (ovules and pollen grains) in flowers which produce seeds as a result of fertilisation
Asexual:
- produce runners - stems which grow horizontally on the surface of the soil and produces new plants genetically identical to the parent plant

Question 26

how does daffodils and onions carry out sexual reproduction and asexual reproduction

Answer 26

Sexual:
- produce **gametes* in flowers —> seeds produced due to fertilisation
Asexual:
- produce bulbs - new bulbs form on the original parent plant and can split off to form a genetically identical plant

Question 27

how does potatoes carry out sexual reproduction and asexual reproduction

Answer 27

Sexual:
- produce **gametes* in flowers —> seeds produced due to fertilisation
Asexual
- produces tubers - are underground structures that form on the original parent bulb and ca split off to form a genetically identical plant