1.5.1: Nucleic acid structure

Question 1

state 2 functions of the DNA

Answer 1

1 - replication for cell division
2 - Carry genetic code for protein synthesis

Question 2

State the 3 types of RNA and their full forms too

Answer 2

1 - mRNA - messenger RNA
2 - tRNA - transfer RNA
3 - rRNA - ribosomal RNA

Question 3

What are the two types of nucleic acids

Answer 3

DNA and RNA

Question 4

how many polynucleotides does a molecule of DNA contain and where is it found

Answer 4

2 - nucleus

Question 5

how many polynucleotides does a molecule of RNA have and where is it found

Answer 5

1 - cytoplasm and nucleus

Question 6

Describe the structure of a general nucleotide

Answer 6

pentose sugar (ribose or deoxyribose), nitrogenous base attached to carbon-1, phosphate group attached to carbon-5

Question 7

what is the full form of ATP

Answer 7

adenosine triphosphate

Question 8

what are the 2 types of nitrogenous bases

Answer 8

purine bases, pyrimidine bases

Question 9

List the purine bases

Answer 9

adenine
guanine

Question 10

list the pyrimidine bases

Answer 10

thymine
cytosine
uracil

Question 11

what are 2 main differences between purine and pyrimidine bases

Answer 11

purine bases are always bigger than pyrimidine bases, purine bases are double ring whereas pyrimidine bases are single ring

Question 12

which bases have complementary base pairing and how many h-bonds are there between each pair

Answer 12

A-T (2 H bonds)
C-G (3 H bonds)
A -U (2 H bonds)

Question 13

What is the relation between purine and pyrimidine bases

Answer 13

they complementary base pair to each other

Question 14

Describe the process of the formation of a DNA molecule

Answer 14

When a condensation reaction occurs between the pentose sugar of one nucleotide and the phosphate group of another, a strong covalent bond called a phosphodiester bond forms.
Repeated condensation reactions results in a single chain of repeating nucleotides which has a strong sugar-phosphate backbone with bases protruding from it. The second polynucleotide chain forms antiparallel to the first running from 5’ to 3’. Hydrogen bonds form between exposed bases that are complementary to each other joining the 2 polynucleotide chains together.

Question 15

how is the feature of the DNA having a sugar-phosphate backbone related to its function

Answer 15

gives strength to the DNA molecule

Question 16

how is the feature of the DNA being two chains held together by weak hydrogen bonds related to its function

Answer 16

chains can be separated for transcription and replication

Question 17

how is the feature of the DNA having a coiled structure related to its function

Answer 17

protects hydrogen bonds therefore reducing corruption of genetic code

Question 18

how is the feature of the DNA having many weak hydrogen bonds related to its function

Answer 18

makes DNA a stable molecule

Question 19

how is the feature of the DNA having a sequencing of DNA bases related to its function

Answer 19

allows information to be stored

Question 20

how is the feature of the DNA being a long molecule related to its function

Answer 20

can store a lot of genetic information

Question 21

what is the difference in the nitrogenous bases present in DNA and in RNA

Answer 21

RNA has uracil instead of thymine

Question 22

Name the 2 scientists who proposed models of the chemical structure of DNA

Answer 22

Watson and Crick