DNA

Question 1

What is the full name of DNA

Answer 1

Deoxyribonucleic acid

Question 2

What shape is DNA?

Answer 2

Double helix

Question 3

What’s the structure of the DNA helix?

Answer 3

2 nitrogen bases bond together to make the steps of the helix; sugar and phosphate chains make up the sugar phosphate backbone which provides structural support

Question 4

What is semi conservative?

Answer 4

The new DNA strand contains one strand that is old and one that is new.

Question 5

What is a nucleotide?

Answer 5

They are the monomers of Nucleic acid that makes up DNA. It is made up of sugar, a phosphate and a nitrogenous base.

Question 6

What are the four nitrogenous bases?

Answer 6

Adenine
Guanine
Thymine
Cytosine

Question 7

What bond is between the two bases of a DNA molecule?

Answer 7

Hydrogen bases

Question 8

What is DNA helicase?

Answer 8

An enzyme that unwinds the double helix during DNA replication.

Question 9

What is DNA polymerase?

Answer 9

An enzyme involved in DNA replication that joins individual nucleotides by forming phosphodiester bonds to produce a DNA molecule and the phosphate sugar backbone of the DNA.

Question 10

What is a mutation?

Answer 10

An error that occurs during DNA replication.

Question 11

Who is Watson and crick?

Answer 11

Developed the 3D double helix model of DNA

Question 12

Which bases are pyrimidines?

Answer 12

Thymine
Cytosine

Question 13

Which bases are purines?

Answer 13

Guanine
Adenine

Question 14

How want rings do purines have?

Answer 14

Double ring

Question 15

How many rings do pyrimidines have?

Answer 15

1

Question 17

Describe the process of DNA packing?

Answer 17

1. DNA is wrapped around histones - protein beads
2. DNA is condensed into a helix (30nm fibre)
3. DNA is looped around a protein core (300nm fibre)

Question 18

Which is the base in RNA that isnt in DNA?

Answer 18

Uracil

Question 19

Which base group is uracil in?

Answer 19

Pyrimidines

Question 20

What are the differences between DNA and RNA?

Answer 20

• in RNA there is no thymine. Thymine is replaced by uracil.
• deoxyribose is replaced by ribose in RNA
• RNA is shorter, DNA is loner
• RNA is single stranded, DNA is double stranded

Question 21

What are ribosomes made up of?

Answer 21

• proteins
• rRNA

Question 22

What do you need for DNA replication?

Answer 22

1. Nucleotides
   - containing deoxyribose sugar
   - phosphate
   - nitrogen containing base
2. Enzymes
   - to join nucleotide together
   - to unwind the helix
   - to carry out proof reading
3. Chemical energy
   - ATP to power the reactions

Question 23

Explain the process of DNA replication.

Answer 23

1. The original DNA molecule unwinds due to the enzyme DNA helicase
2. DNA helicase causes the 2 strands of DNA to separate
3. Free nucleotides in the nucleoplasm are attracted to their complementary base pairs.
4. The strong phosphate sugar backbone is rejoined by DNA polymerase forming 2 identical strands of DNA because the strands each contain half of the original material it is called the semi conservative method of replication

Question 24

What’s the replication fork?

Answer 24

Very active area where DNA replication takes place