Lec 9 - Molecular Biology of the Gene

Question 1

Who set the stage for the discovery of DNA when he was trying to develop a vaccine against pneumonia?

Answer 1

Frederick Griffith

Question 2

Frederick Griffith studied two strains what are these?

Answer 2

a harmless (R) and a pathogenic (S) strain

Question 3

What structural feature of virus like bacteriophage T2 made them ideally suited for the Hershey-Chase experiment?

Answer 3

Phage Coat: Protein
Phage Genome : DNA

Question 4

How does complementary base pairing make it possible for the replication of DNA?

Answer 4

Complementary base pairing provides a mechanism for accurate and efficient DNA replication. It guarantees that the correct sequence of nucleotides is maintained in the newly synthesized strands, preserving the genetic code.

Question 5

Replication of chromosomal DNA begins at particular sites called?

Answer 5

origins of replication

Question 6

What do you call short stretches of DNA having a specific sequence of nucleotides?

Answer 6

origins of replication or primer lelz

Question 7

What are the enzymes that link DNA nucleotides to a growing daughter strand?

Answer 7

DNA Polymerases

Question 8

When is DNA replication terminated?

Answer 8

When it reaches the telomere region of repetitive DNA close to the ends of the chromosomes

Question 9

Termination requires what? Cite 2.

Answer 9

1. A termination site sequence in the DNA
2. A protein which binds to this sequence to physically stop the DNA replication

Question 10

________ are the links between genotype and phenotype

Answer 10

Proteins

Question 11

What is a hereditary condition in which urine is dark because it contains chemical called alkapton.

Answer 11

Alkaptonuria

Question 12

What are the functions of transcription and translation?

Answer 12

DNA -> RNA -> Protein (Diagram)

Question 13

The sugar unit in the backbone of RNA is ______; it is ______in DNA

Answer 13

ribose, deoxyribose

Question 14

This type of RNA is formed directly by DNA transcription. Post transcription processing converts the heterogeneous nuclear RNA to messenger RNA

Answer 14

Heterogeneous nuclear RNA (hnRNA)

Question 15

This type of RNA facilitates the conversion of heterogeneous nuclear RNA to messenger RNA. It contains from 100 to 200 nucleotides.

Answer 15

Small nuclear RNA (snRNA)

Question 16

This type of RNA carries instructions for protein synthesis (genetic information) to the sites for protein synthesis. The molecular mass of messenger RNA varies with the length of the protein whose synthesis it will direct.

Answer 16

Messenger RNA (mRNA)

Question 17

This type of RNA combines with specific proteins to form ribosomes, the physical sites for protein synthesis. Ribosomes have molecular masses on the order of 3 million amu.

Answer 17

Ribosomal RNA (rRNA)

Question 18

This type of RNA delivers amino acids to the sites for protein synthesis. Transfer RNAs are the smallest of the RNAs, possessing only 75 90 nucleotide units.

Answer 18

Transfer RNA (tRNA)

Question 19

Process by which DNA directs the synthesis of hnRNA/mRNA molecules that carry the coded information needed for protein synthesis

Answer 19

Transcription: RNA Synthesis

Question 20

Process by which messenger RNA (mRNA) is decoded in a ribosome, outside the nucleus, to produce a specific amino acid chain, or polypeptide. The polypeptide later folds into an active protein and performs its functions in the cell.

Answer 20

Translation: Protein Synthesis

Question 21

A three nucleotide sequence in an mRNA molecule that codes for a specific amino acid.

Answer 21

Codon

Question 22

What are the 3 stages of Translation: Protein synthesis?

Answer 22

Stage 1 - Initiation
Stage 2 - Elongation
Stage 3 - Termination