DNA

Question 1

What are nucleic acids?

Answer 1

Linear polymers of nucleotides

Question 2

How many nucleotides are there?

Answer 2

5 A T G C and U

Question 3

What structure does DNA adopt?

Answer 3

Complementary double helix -no 3D structure

Question 4

What is the base sugar used in DNA? and RNA?

Answer 4

DNA uses deoxyribose and RNA uses ribose -the 2’H changes

Question 5

What different types of bases are there?

Answer 5

2-purines (largest 2 cycles) and pyrimidines (smallest 1 cycle)

Question 6

What is a nucleoside?

Answer 6

Its a nucleotide without a phosphate-just ribose and base

Question 7

How is DNA organised when read? What is DNA primary sequence?

Answer 7

5’ to 3’, the other strand is going the other way (5’ end where 3’ end of the other)-the primary sequence is the sequence read 5’ to 3’

Question 8

How are groups organised in the double helix?

Answer 8

they tun antiparallel, with the ribose sugars on the outside of the helix. The bases are flat and parrallel to one another. They have major and minor grooves

Question 9

What kind of bonds libk the bases together?

Answer 9

Hydrogen bonds. 2 for A-T, 3 for C-G

Question 10

What is the karyotype? Do E.coli have one? When can it been seen?

Answer 10

Karyotype is an ogrnaised profile of someones chrs (46). E coli only has 1 -no karyotype. Chr can be seen only during mitotic divison. during interphase, chr are less dense and cannot be seen

Question 11

How is eukaryotic packaged?

Answer 11

Nucleosome-DNA around positive 8 histones that wrap DNA around it (2 turns)-also called beads on a string.
30nm fiber-Histones 1 sit between beads and pull DNA together.
Chromatin fiber-30nm chromatin is brought together again (700nm) and packed into chr