Genetics

Question 1

What is DNA?

Answer 1

Genetic material

Question 2

Where is DNA found in a cell?

Answer 2

The nucleus

Question 3

What is the definition of a gene?

Answer 3

A short section of DNA that codes for a particular protein

Question 4

What is a genome?

Answer 4

The entire genetic material found in an organism

Question 5

What is the definition of an allele?

Answer 5

Different form of a gene

Question 6

What is a nucleotide made up of?

Answer 6

A phosphate, a sugar (deoxyribose) and a base

Question 7

What are the 4 bases called?

Answer 7

A, T, C and G

Question 8

What makes up the ‘backbone’ of DNA?

Answer 8

Phosphate and sugar

Question 9

What shape is DNA folded into?

Answer 9

A Double helix

Question 10

What is the base pairing rule?

Answer 10

The bases A and T join together
and C and G join together.

Question 11

How are chromosomes arranged?

Answer 11

In functional pairs in the nucleus of cells, except for the gametes in which there is only one chromosome

Question 12

How are humans unique even though everyone contains the same 4 bases (ATCG)?

Answer 12

The sequence of bases in each person is different

Question 13

What smaller units make up proteins?

Answer 13

Amino acids

Question 14

How many bases code for 1 amino acid and what is this called?

Answer 14

3
Base triplet

Question 15

The coding strand of DNA consists of 90 bases. How many amino acids does this section code for?

Answer 15

30

Question 16

If a section of DNA contained 30% bases of Thymine (T). How many Guanine (G) bases are there?

Answer 16

If there are 30% Thymine, then there must be 30% Adenine

Therefore there would be 40% left to split between G and C

G and C would both have 20% each

Question 17

Name the 2 types of cell division

Answer 17

Mitosis and Meiosis

Question 18

What is the function (job) of Mitosis?

Answer 18

-Replaces worn out cells
- Repairs damaged tissue
-Growth

Question 19

Where does Mitosis occur?

Answer 19

Every cell in the body except for the sex cells

Question 20

How many daughter cells are produced in Mitosis?

Answer 20

2

Question 21

Are the daughter cells in Mitosis genetically identical to the parent cell or does it show variation?

Answer 21

Genetically identical

Question 22

Are the daughter cells produced in Mitosis: diploid or haploid?

Answer 22

Diploid

Question 23

What is Meiosis?

Answer 23

A type of cell division that produces cells that have half the normal chromosome number

Question 24

Where does Meiosis occur?

Answer 24

The sex organs (testes and ovaries)

Question 25

How many daughter cells are produced in Meiosis?

Answer 25

4 haploid daughter cells

Question 26

What is independent assortment?

Answer 26

A meiosis the chromosomes are re-assorted in the formation of gametes

Question 27

What does the term homozygous mean?

Answer 27

Both alleles of a gene are the same

Question 28

What does the term heterozygous mean?

Answer 28

Both alleles of a gene are different

Question 29

What is a genotype?

Answer 29

The genetic code of an organism e.g. Bb or BB

Question 30

What is a phenotype?

Answer 30

The physical appearance of an individual e.g. brown eyes

Question 31

Who is the founder of genetics?

Answer 31

Gregor Mendel

Question 32

How many chromosomes are in a normal cell?

Answer 32

46 chromosomes

Question 33

Define the term recessive

Answer 33

You would need 2 copies of the allele to be seen in its phenotype

Question 34

Give an example of a sex linked diseased

Answer 34

Hemophilia or colour blindness

Question 35

Give a symptom of Haemophilia

Answer 35

Blood does not clot so causes excessive bleeding

Question 36

What does the term carrier mean?

Answer 36

An individual has one copy of the harmful allele but don’t show the condition

Question 37

How can you identify if an individual has Down syndrome

Answer 37

They have an extra chromosome i.e. they have 47 chromosomes

Question 38

What is genetic screening?

Answer 38

A test for the presence of harmful alleles or genetic abnormalities