Chromosome, Genes & DNA

Question 1

Chromosome

3 marks

Answer 1

Genetic structures that usually occur in functional pairs in the nucleus of cells
(except in gametes + bacteria).


Question 2

Coding strand

2 marks

Answer 2

Bases on one strand of DNA used as code for amino acids.

Question 3

Gene

(7 marks)


Answer 3

• Basic unit of genetic material inherited from parents.
• It is a short length of DNA found on a chromosome that codes for a particular characteristic or protein
• it controls part of a cell’s chemistry - particularly protein production.

Question 4

Genome

2 marks

Answer 4

Complete set of DNA found in an organism.

Question 5

Nuclei

1 mark

Answer 5

The plural of nucleus.

Question 6

Organism

3 marks

Answer 6

Animal, plant or microorganism.

Question 7

Chromosomes are thin strands of…

2 marks

Answer 7

DNA (deoxyribonucleic acid).

Question 8

What are Chromosomes subdivided into?

1 mark

Answer 8

Genes

Question 9

In most cells where are chromosomes located?

2 marks

Answer 9

In functional pairs in the nucleus.

Question 10

Number of Chromosomes in Humans

2 marks

Answer 10

46 arranged in 23 pairs.

Question 11

Do not have pairs of chromosomes in their nuclei

1 mark

Answer 11

Gametes

Question 12

Do not have a nucleus

1 mark

Answer 12

Bacterial cells

Question 13

The entire genetic material of an organism

1 mark

Answer 13

The genome.

Question 14

Alleles

1 mark

Answer 14

Variations of the same gene.

Question 15

Example of Alleles

2 marks

Answer 15

Eye colour is the gene - blue, green, brown etc. are alleles.

Question 16

Alleles for brown eyes are

1 mark

Answer 16

Dominant

Question 17

Alleles for blue eyes are

1 mark

Answer 17

Recessive

Question 18

2 Homozygous Brown Eye Alleles

2 marks

Answer 18

2 of the Same Dominant Alleles

Question 19

2 Homozygous Blue Eye Alleles

2 marks

Answer 19

2 of the Same Recessive Alleles

Question 20

2 Heterozygous Alleles

1 mark

Answer 20

2 Different Alleles

Question 21

DNA molecules are

3 marks

Answer 21

Large + complex - carry the genetic code that determines the characteristics of a living organism.

Question 22

The backbone of the DNA double helix consists of

3 marks

Answer 22

Alternating phosphate + deoxyribose sugar molecules.

• Interlinking bases hold the 2 sides together.

Question 23

Four different bases exist in DNA:

4 marks

Answer 23

A = adenine

T = thymine

C = cytosine

G = guanine

Question 24

Complimentary bases of DNA:
Base-Pairing Simplified

(2 marks)

Answer 24

A - T

C - G

Question 25

Complimentary bases of DNA: Base-Pairing Explained (4 marks)

Answer 25

Adenine - Thymine Cytosine - Guanine

Question 26

Base-pairing rule | 2 marks

Answer 26

As A is complementary to T + C is complementary to G, they pair up.

Question 27

A Nucleotide consists of | 3 marks

Answer 27

1 phosphate, 1 Deoxyribose sugar + 1 base.

Question 28

Each individuals DNA is | 1 mark

Answer 28

Unique

Question 29

Apart from _________ _____, no one shares the same sequence of bases. (1 mark)

Answer 29

Identical Twins

Question 30

Share the same sequence of bases (in DNA) | 1 mark

Answer 30

Identical Twins

Question 31

What do identical twins share? | 2 marks

Answer 31

The same sequence of bases (in DNA).

Question 32

DNA works by | 3 marks

Answer 32

Providing a code for cells to make a particular protein (e.g an enzyme). - This is the DNA Code

Question 33

The DNA code | 2 marks

Answer 33

Sequence of bases in DNA.

Question 34

Where the DNA Code is found | 1 mark

Answer 34

On the coding strand.

Question 35

3 bases (in DNA) | 1 mark

Answer 35

A base triplet.

Question 36

3 bases (a base triplet) code for | 1 mark

Answer 36

1 amino acid.

Question 37

Amino acids are joined in this order to make the protein | 3 marks

Answer 37

A sequence of base triplets (found on the coding strand) | - joined together to make a protein.

Question 38

The Base Triplet Hypothesis | 3 marks

Answer 38

The correct base triplets, arranged in the correct order along the coding strand. (This is important)