DNA

Question 1

What is the full name of DNA?

Answer 1

Deoxyribonucleic acid

Question 2

What is DNA?

Answer 2

An important information carrying molecule.

Question 3

Why can’t the DNA leave the nucleus?

Answer 3

Because it’s too big >:( to go through the nucleus pores

Question 4

Fill in the blanks:
The DNA itself is a —— with 2 — chains held together by — bonds between specific —— pairs

Answer 4

The DNA itself is a double helix with 2 polynucleotide chains held together by hydrogen bonds between specific complimentary base pairs.

Question 5

True or false, DNA is the genetic material in all living and non living organisms.

Answer 5

True ye

Question 6

Is DNA parallel?

Answer 6

no, its anti parallel

Question 7

Does DNA have codes?

Answer 7

yes (oui)

Question 8

What are the components of DNA?

Answer 8

deoxyribose, a phosphate group and one of the 4 organic bases

Question 9

Fill in the blanks:
In terms of structure, DNA has a – – made up of the repeated joining of the sugar and phosphate group of each –.

Answer 9

1. phosphate backbone
2. nucleotide

Question 10

What does the DNA code tell the cell?

Answer 10

What to do, what proteins to make.

Question 11

What is the name of the study of genomes?

Answer 11

Genomics

Question 12

What is the difference between eukaryotic DNA and prokaryotic DNA?

Answer 12

In eukaryotes, DNA is found mainly in the nucleus as it is a membrane bound organelle, but there is some DNA in chloroplasts and mitochondria.
In prokaryotes, DNA is not enclosed in a membranous envelope, it sits freely as a loop of DNA in the cytoplasm.

Question 13

Who created the first x-ray of the structure of DNA?

Answer 13

Rosalind Franklin, but she did not receive a noble prize due to her dying of cancer from her own experiment.

Question 14

Which technique was used to find the first x-ray of DNA?

Answer 14

X-ray diffusion

Question 15

Why was the discovery of DNA important?

Answer 15

Because it explained how DNA was copied and provided information on evolution, gene theory, medicines, etc.

Question 16

Why did scientists initially deny the DNA structure?

Answer 16

Because it was a chemically simple molecule

Question 17

What are the 4 organic bases?

Answer 17

Adenine (A)
Thymine (T)
Guanine (G)
Cytosine (C)

Question 18

What are the pairs of the organic bases?

Answer 18

Adenine always binds with thymine.
Guanine always binds with Cytosine.

Question 19

What bonds are between the organic bases? How many for each pair?

Answer 19

1. Hydrogen bonds
2. 3 between G and C, 2 between A and T

Question 20

Which of the organic bases are purine and pyrimidine?

Answer 20

Adenine and Guanine are purine.
Cytosine and Thymine are pyrimidine.

Question 21

Which enzyme:
Breaks down the hydrogen bonds between the bases, causing the two strands of DNA to separate and expose the nucleotides base in that region?

Answer 21

DNA helicase

Question 22

What does DNA polymerase do?

Answer 22

It is an enzyme that joins DNA nucleotides together in a condensation reaction, forming phosphodiester bonds, during DNA replication

Question 23

What are the carbon atoms of a sugar molecule numbered at?

Answer 23

1’ to 5’

Question 24

What is the bond called to the hydroxyl group of the 5’ carbon of one sugar group and the hydroxyl group of the 3’ carbon of the sugar group of the next nucleotide?

Answer 24

5’-3’ phosphodiester linkage

Question 25

What are the 4 steps of transcription?

Answer 25

Step 1:
- DNA Helicase breaks the hydrogen bonds on a section of DNA containing the gene for the desired protein. Nucleotides are exposed.

Step 2:
- RNA polymerase moves along one of the two DNA strands (the template strand). It joins complementary nucleotides on the exposed template strand to from a pre-mRNA strand.

Step 3:
- The DNA bases re-join as the RNA polymerase moves along.

Step 4:
- Pre-mRNA can then be spliced before it leaves the nuclear pores.

Question 26

Describe and explain the Splicing of pre-mRNA

Answer 26

DNA contains regions which code for proteins (called exons) and introns which are the regions of DNA that do not code for proteins.
In pre-mRNA both exons and introns are present but the introns must be removed or ‘spliced out’ to only leave exons.
- Introns INterrupt the exons to they are removed.