B1.7 - Genetic Variation

Question 1

What do genes carry?

Answer 1

DNA, the information that results in plants and animals having similar characteristics to their parents

Question 2

How are genes passed on?

Answer 2

In the sex cells from which the offspring develop

Question 3

What does the nucleus of a cell contain?

Answer 3

Chromosomes

Question 4

What are chromosomes?

Answer 4

They carry genes which control the characteristics of the body

Question 5

Different genes control…

Answer 5

…the development of different characteristics of an organism

Question 6

What may differences in the characteristics of different individuals of the same kind be due to?

Answer 6

• The genes they have inherited (genetic causes
• The conditions in the they have developed (environmental causes)
• a combination of both

Question 7

What are the two types of reproduction?

Answer 7

Sexual and asexual

Question 8

What happens with the cells during sexual reproduction?

Answer 8

The joining (fusion) of male and female gametes. The mixture of genetic information from 2 parents leads to variety in offspring

Question 9

What happens with the cells during sexual reproduction?

Answer 9

No fusion of gamete, only one parent needed. There is no mixing of genetic information so no genetic variation. Known as clones.

Question 10

How can new plants be produced quickly and cheaply?

Answer 10

By taking cuttings form another plant They are genetically identical to the parent plant.

Question 11

What is tissue culture?

Answer 11

Using small groups of cells from part of a plant to clone a new one

Question 12

What is an embryo transplant?

Answer 12

Splitting apart cells from a developing animal embryo before they become specialised, then transplanting the identical embryos into host mothers

Question 13

What is adult cell cloning?

Answer 13

the nucleus is removed from an unfertilised egg cell, then the nucleus from an adult cell is inserted. An electric shock then causes the egg cell to begin to divide to form embryo cells, which contain the genetic info of the adult cell. When the embryo is a ball of cells, it is inserted into a womb.

Question 14

How can genes from chromosomes be cut out of the cell?

Answer 14

Using enzymes

Question 15

How can a plant or animal be given desired characteristics?

Answer 15

Genes can be transferred to the cells at an early stage of development

Question 16

What are GM crops?

Answer 16

Ones which have had their genes changed

Question 17

What are some examples of GM crops?

Answer 17

Ones that are resistant to insect attack or herbicides, which tend to have a higher yield.

Question 18

What are some concerns over GM crops?

Answer 18

• Their effect on wild flowers and insects

- Uncertainty abut the effects of consuming GM crops