DNA

Question 1

Whats DNA structure?

Answer 1

DNA is made from 2 strands of molecules called nucleotides.
Each nucleotides contains a sugar molecule, a phosphate group and a nitrogen containing group called a base.

Question 2

What are the bases in DNA?

Answer 2

adenine (A), thymine (T), cytosine (C), guanine (G)

Question 3

Whats the base pairing rule?

Answer 3

A - T
C - G

Question 4

Whats a gene?

Answer 4

A section of DNA which codes for a specific protein.

Question 5

How is protein synthesized?

Answer 5

Occurs in two stages: transcription and translation.
Transcription is the transfer of genetic instructions in DNA to mRNA in the nucleus. It includes three steps: initiation, elongation, and termination. After the mRNA is processed, it carries the instructions to a ribosome in the cytoplasm.
Translation occurs at the ribosome, which consists of rRNA and proteins. In translation, the instructions in mRNA are read, and tRNA brings the correct sequence of amino acids to the ribosome. Then, rRNA helps bonds form between the amino acids, producing a polypeptide chain.

Question 6

Whats the difference between DNA and RNA?

Answer 6

1. DNA is double helix, RNA is single helix.
2. DNA contains the sugar deoxyribose, RNA contains ribose.

Question 7

Whats a duplication mutation?

Answer 7

The nucleotide is inserted twice instead of once. The whole gene is different and will now code for an entirely different protein.

Question 8

Whats a deletion mutation?

Answer 8

A nucleotide is missed out. The whole gene is different and will now code for an entirely different protein.

Question 9

Whats a substitution mutation?

Answer 9

A different nucleotide is used. The triplet of the bases in which the mutation occurs is changed and it may code for a different amino acid.

Question 10

Whats an inversion mutation?

Answer 10

The sequence of bases in a triplet is reversed. This may result in a different amino acid and altered protein structure.

Question 11

Whats a homologous pair?

Answer 11

Pairs of matching chromosomes are called homologous pairs. They carry genes for the same features

Question 12

Whats a diploid cell?

Answer 12

Cells with chromosomes in pairs.

Question 13

Whats an allele?

Answer 13

Alleles are matching genes; one from our biological mother, one from our biological father. We have two copies of every gene.