Genes

Question 1

Define genome.

Answer 1

entire genetic material of an organism that is arranged into chromosomes

Question 2

What is DNA?

Answer 2

1. Deoxyribonucleic acid

2. Two strands twisted to form a double helix polymer - made up of repeating units called nucleotides

Question 3

Describe fully the features of nucleotides. (3)

Answer 3

1. Monomer of DNA w fixed complementary base pairings bound by hydrogen bonds.
   • A (adenine) and T (thymine)
   • C (cytosine) and G (guanine)
2. Phosphate, pentose sugar, nitrogenous base
3. Alternating sections of phosphates and sugars form backbone of double helix.

Question 4

What is the role of a chromosome?

Answer 4

1. 23 pairs in nucleus of human body cell
2. Long molecule of DNA
3. Contain sections called genes

Question 5

What is a gene?

Answer 5

1. Small section of DNA

2. Contains instructions that code for sequence of amino acids, that combine to form a specific protein.

Question 6

What is a protein?

Answer 6

1. Polymer of amino acids connected by peptide bonds
2. 2 types
   • structural (bone)
   • functional (enzymes)

Question 7

What is genetic code? What is the significance of this?

Answer 7

1. Genetic code = order bases in DNA

2. Determines amino acid sequence which determines the protein made, affecting structure and function

Question 8

What is a triplet code?

Answer 8

Set of 3 nucleotides that code for specific amino acid.