Genetic Diagrams

Question 1

What are alleles?

Answer 1

Different versions of the same gene

Question 2

How are alleles represented in genetic diagrams?

Answer 2

Letters

Question 3

What does Homozygous mean?

Answer 3

If an organism has 2 alleles for a particular gene that are the same

Question 4

What does Heterozygous mean?

Answer 4

If an organism has 2 alleles for a particular gene that are different

Question 5

If the 2 alleles are different, only one can determine what [ ] is present.

Answer 5

characteristic

Question 6

What is a dominant allele?

Answer 6

The dominant allele is the allele for the characteristic that is shown. Capital letter

Question 7

What is a recessive allele?

Answer 7

For an organism t display a recessive allele, both its alleles must be recessive. Small letter

Question 8

What needs to happen for a dominant allele to be shown?

Answer 8

The organism can either be Cc or CC. because the dominant allele overrules the recessive alleles one if the animal is heterozygous

Question 9

What’s a genotype?

Answer 9

Means what alleles you have

Question 10

What’s a phenotype?

Answer 10

Means the actual characteristic (brown hair)

Question 11

What’s a monohybrid?

Answer 11

When you cross 2 parents to look at just 1 characteristic

Question 12

What is cystic fibrosis?

Answer 12

A genetic disorder of the cell membranes. It results in the body producing a lot of thick sticky mucus in the air passages and in the pancreas

Question 13

cystic fibrosis is caused by [ ] allele

Answer 13

recessive ‘f’

Question 14

About 1 in [ ] carry the cystic fibrosis allele

Answer 14

25

Question 15

Who are carriers of cystic fibrosis?

Answer 15

Because it’s recessive, people with only one copy of the allele won’t have the disorder = carriers

Question 16

If both parents are carriers what is the chance that their child will have cystic fibrosis?

Answer 16

1/4

Question 17

What is polydactyly?

Answer 17

A genetic disorder where a baby’s born wit extra fingers or toes. - not life threatening

Question 18

polydavtyly is caused by a [ ] allele, ‘[ ]’

Answer 18

Dominant, ‘D’

Question 19

Talk about who will inherit polydactyly

Answer 19

It can be inherited if just 1 parent carries the defective allele.
The parent that has the defective allele will be a sufferer too since the allele is dominant

Question 20

If 1 parent is heterozygous for polydactyly and the other parent is normal, what is the chance that their child will have polydactyly?

Answer 20

50%