Energy Transfer

Question 1

what are the two types of variation?

Answer 1

Genetic variation and Environmental variation

Question 2

what are characteristics determined by?

Answer 2

The genes inherited from parents

Question 3

what is genetic variation?

Answer 3

The difference between species in genes so that they are not genetically identical

Question 4

what is environmental variation?

Answer 4

The differences between members of the same species caused by environmental differences

Question 5

how many pairs of chromosomes are there in a human cell?

Answer 5

23 pairs

Question 6

what is sexual reproduction?

Answer 6

Sexual reproduction is the fusion of female and male gametes, because there are two parents the offspring contains a mixture of their parents’ genes

Question 7

what is asexual reproduction?

Answer 7

Asexual reproduction involves only one parent. There’s no fusion of gametes, no mixing of chromosomes and no genetic variation between parent and offspring. The offspring are genetically identical to the parent - they’re clones

Question 8

how does asexual reproduction work?

Answer 8

1. X shaped chromosomes have two identical halves
2. Each chromosome splits down the middle
3. They form two identical sets of half chromosome and a membrane forms around each set
4. Finally the DNA replicates itself to form identical cells with a complete set of chromosomes

Question 9

how is cloning done?

Answer 9

1. A selected embryo and selected sperm artificially fertilise
2. the embryo develops and splits
3. These are put into several uteruses and are born identical

Question 10

what are the issues of cloning?

Answer 10

1. There is a reduced gene pool
2. Possible health issues
3. Slippery slopes to human cloning

Question 11

what are the benefits of cloning?

Answer 11

1. There can be more study and understanding of ageing etc.

2. Endangered species can be preserved

Question 12

what is genetic engineering?

Answer 12

A ‘useful’ gene is cut from one organisms chromosome using enzymes and then inserted into another organisms chromosome to make useful products

Question 13

what are GM crops?

Answer 13

Genetically Modified crops are crops that have had their genes modified to make them resistant to viruses, insects and herbicides

Question 14

what is gene therapy?

Answer 14

Gene therapy is the change of genes to eliminate inherited diseases