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**