National 5 Biology: KA3: DNA and the Production of Proteins

Question 1

Define:

Chromosomes

Answer 1

Thread-like structures found in the nucleus that contain genetic information.

Question 2

Define:

Gene

Answer 2

Sections of DNA containing coded instructions for making a specific protein.

Question 3

What shape is DNA?

Answer 3

Double helix structure

Question 4

What are the rungs of the double helix?

Answer 4

DNA bases

Question 5

What bonds DNA together?

Answer 5

Chemical units.

Question 6

What do these chemical units do?

Answer 6

Bond as complementary base pairs to hold the double helix together.

Question 7

Which bases pair with which?

Answer 7

A - T

C - G

Question 8

Define:

Organism

Answer 8

Living being made of single or many cells

Question 9

Define:

Cell

Answer 9

Basic unit of living things.

Question 10

Define:

Nucleus

Answer 10

Organelle in cells which contains genetic information

Question 11

Define:

Gene

Answer 11

Unit of inheritance which controls a characteristic.

Question 12

Define:

DNA

Answer 12

Chemical which contains the genetic code.

Question 13

Define:

Base pair

Answer 13

Small chemical units which make up DNA joined like rungs on a ladder.

Question 14

Who was credited for the discovery of the structure of DNA? [3]

Answer 14

Francis Crick, James Watson and Maurice Wilkins

Question 15

When was the discovery of the structure of DNA made?

Answer 15

In February 1953

Question 16

Who else contributed to the discovery of the structure of DNA?

Answer 16

Rosalind Franklin.

Question 17

What did Rosalind Franklin do?

Answer 17

Took an image of the structure (Photograph 51) - using x-ray crystallography.

Question 18

Where was the discovery of the structure made?

Answer 18

Cambridge University

Question 19

Who didn’t get a Nobel Prize for their work? Why?

Answer 19

Rosalind Franklin because she died of cancer in 1958 - four years before the prize was awarded.

Question 20

What does DNA stand for?

Answer 20

Deoxyribonucleic acid

Question 21

What do bases hold?

Answer 21

Genetic code.

Question 22

What is the genetic code?

Answer 22

Instructions for how an organism will develop.

Question 23

Specific patterns of bases give what?

Answer 23

Specific instructions

Question 24

What does each chromosome contain?

Answer 24

Multiple genes.

Question 25

What does each gene contain?

Answer 25

A specific sequence of DNA bases.

Question 26

How many different DNA bases are there?

Answer 26

4

Question 27

What are the 4 bases of DNA?

Answer 27

ATCG

adenine, thymine, guanine, cytosine

Question 28

What did Chargaff discover?

Answer 28

Number of A’s = number of T’s

Number of C’s = number of G’s

Question 29

What are proteins?

Answer 29

Long chains of amino acids folded into specific shapes.

Question 30

Define:

Amino Acids

Answer 30

Building blocks of proteins

Question 31

How many amino acids are there?

Answer 31

20

Question 32

What is the order of amino acids determined by?

Answer 32

The DNA sequence

Question 33

How does DNA become a protein?

Answer 33

DNA base sequence –> chain of amino acids –> protein

Question 34

How many molecules of DNA are in a chromosome?

Answer 34

2

Question 35

What are they held together by?

Answer 35

Hydrogen bonds

Question 36

What does mRNA mean?

Answer 36

Messanger RNA

Question 37

Why are the instructions for making proteins coped onto mRNA?

Answer 37

The instructions have to go through the cytoplasm to get to the ribosomes and during this journey, they could get lost / damaged.

Question 38

What happens to the original / master copy?

Answer 38

Stays in the nucleus.