DNA and Chromsomes

Question 1

to explain why new nucleotides can only be added in a 5’ to 3’ direction.

Answer 1

DNA polymerase has a specific active site dna polymerase can only bind to 5’ of strand

Question 2

HSV ( virus) infects nerve cells in the face Explain why it infects only nerve cells.

Answer 2

attachment proteins complementary to receptors which are only found on nerve cells

Question 3

Suggest one advantage of programmed cell death (line

Answer 3

prevents unwanted cells ( specify to a02) replicating

Question 4

DNA is a polymer. What is the evidence from the diagram that DNA is a

polymer?

Answer 4

• made up of different monomers

Question 5

The events that take place during interphase and mitosis lead to the production of two genetically identical cells. Explain how.

Answer 5

interphase- DNA is replicated through complimentary base paring ( semi conservative)
chromatids moved to opposite poles, nucleus reforms and cytoplasm split into 2 genetically identical daughter cells

Question 6

The student cut thin sections of tissue to view with an optical microscope.
Explain why it was important that the sections were thin.

Answer 6

so light could pass through so cells can be viewed through microscope

Question 7

DNA vs RNA

Answer 7

DNA- deoxyribose, linear, longer, thymine
RNA- ribose, circular, shorter, uracil
- both have phosphodiester bonds, polynucleotides