Science: Genes

Question 1

Scientists believe that the organisms which we see on Earth today have gradually developed over millions of years, this is known as XXXXX

Answer 1

EVOLUTION

Question 2

Who came up with the concept of NATURAL SELECTION
+ what is it

Answer 2

Charles Darwin

he said that only the best adapted animals will survive to pass on their genes, weaker animals will die out

Question 3

What is the name for when all the animals in a species dies out?

Answer 3

EXTINCTION

Question 4

Extinction can be caused by:
(5 examples)

Answer 4

• Changes to the environment
  • Destruction of habitat
  • New diseases
  • Introduction of new predators
  • Increased competition

Question 5

What is biodiversity

Answer 5

When there is a good variety of species in an ecosystem

Question 6

How many chromosomes each do sperm and eggs have?

Answer 6

23 chromosomes each

Question 7

What contains all your genetic material in your body?

Answer 7

DNA contains your genes
DNA make up chromosomes - of which each cell in your body has 46

Question 8

How are characteristics passed on from parent to child?
How does it work?

Answer 8

Via genes. You have 2 alleles (gene) for each characteristics - one from each parent

• Dominant alleles will cause the characteristic to be displayed even if they are with another allele, this is represented by a capital letter
• Recessive alleles will not be displayed as characteristics unless there are two of the same allele, they are the characteristic least likely to be shown, this is represented by a small letter

Question 9

What is genetic modification?

+ examples?

Answer 9

Genetic modification is the process which scientists can use in order to alter the genes of an organism

Examples of this include altering cotton to produce higher yields, altering bacteria genes to prod