DNA replication and Structure

Question 1

Why is DNA replication Important ?

Answer 1

meiosis and mitosis would slowly halve the size of the genome until each cell would die, which probably would not take long.

Therefore, it is important that DNA doubles itself to account for the cells splitting during mitosis/meiosis. DNA replication is similar to RNA transcription.

Question 2

How are Proteins Produced and Instructed ?

Answer 2

They are produced by the ribosome and are instructed by the mRNA

Question 3

What is Template Polymerisation ?

Answer 3

The sequence of a nucleotides in an existing DNA strand controls the sequence in which nucleotides are joined together in an new DNA strand .

Question 4

What does Each monomer consist of in a single DNA strand which is Nucleotide consist of two points ?

Answer 4

A sugar (deoxyribose) with a phosphate group attached to a base which is either adenine, guanine , thymine and Cytosine .

Question 5

What happens in living cells?

Answer 5

DNA is not synthesised as a free strand in isolation , bt on a template form by pre existing DNA strand .The bases of the strand being synthesises complementary structures of the BASES .

Question 6

Steps of DNA replication

Answer 6

1. the two strands of the helix have to be separated, to allow the binding of the replication machinery. This occurs through the binding of the enzyme DNA helicase.
2. DNA helicase is able to detach the strands by splitting the hydrogen bonds between the bases. DNA helicases act at specific regions of the DNA called origins of replication. The unwinding of the two strands by DNA helicase creates a replication fork, a Y-shaped structure where each prong is a single strand of DNA. Which helicase moves along the strands, creating a replication bubble.
3. The separated strands provide a template for synthesising a new strand. Proteins called single-strand binding proteins coat the separated strands keeping them from re-forming a double helix.

4.