Molecular Biology

Question 1

What is DNA composed of

Answer 1

Deoxyribonucleotides

Question 2

What are the components of deixyribonucleotides

Answer 2

A purine or pyrimidine base
A deoxyribose sugar
A phosphate group

Question 3

What is a nucleotide

Answer 3

A molecule with all the components of deoxyribonucleotides

Question 4

What is a nucleoside

Answer 4

A molecule with only the first two components of a nucleotide but no phosphate group

Question 5

How many rings does a purine base have

Answer 5

it has 2 rings

Question 6

how many rings does a pyrimidine base have

Answer 6

it only has 1 ring

Question 7

What is DNAs primary structure

Answer 7

Its the sequence of the base pairs

Question 8

What is DNAs secondary structure

Answer 8

Formed by the complimentary base pairing of two strands of DNA

Question 9

How does base pairing of the secondary DNA structure occur

Answer 9

Thro hydrogen bonding between a purine and pyrimidine base that matches up to provide optimal hydrogen bonding contact

Question 10

What does the back bone of DNA hold

Answer 10

It has the sugars and phosphates

Question 11

What are the steps for the central dogma of molecular biology

Answer 11

Replication, transcription, translation

Question 12

What happens during replication for the central dogma

Answer 12

DNA synthesis or copying DNA

Question 13

What happens during transcription of the cental dogma

Answer 13

DNA provides template for production of messenger RNA (mRNA)

Question 14

What is mRNA

Answer 14

in essence it “reads” the info in DNA and brings it to the site of protein synthesis, the ribosome

Question 15

What happens during Translation of the central dogma

Answer 15

Process by which the info carried in mRNA is used to make actual proteins

Question 16

What does mRNA provide for protein building

Answer 16

a template for the amino acids carried by transfer RNA (tRNA) to be build into proteins of the correct sequence

Question 17

Reverse transcription

Answer 17

Some virus which are able to take RNA and reverse the process to create DNA

Question 18

Semi-conservative replication

Answer 18

When creating new strains of DNA each new strand with always have at least one older stand as well as a newer one

Question 19

What does RNA contain as basic components

Answer 19

Same as DNA which is has a Base, sugar and phosphate

Question 20

What are the two structural differences between RNA and DNA

Answer 20

The sugar in RNA contains a hydroxyl group at the 2’ position
RNA does not contain the pyrimidine base thymine; it has the pyrimidine base of uracil

Question 21

What differs in RNA compared to DNA with its secondary structure

Answer 21

Can use either intermolecular or intramolecular base pairing while DNA only has intermolecular base pairing

Question 22

What can RNA do that DNA can not in terms of twisting and folding

Answer 22

DNA can only form double helix while RNA can Twist and fold in 3D forms to create tertiary structures

Question 23

What are the different types of RNA and what are these based off of

Answer 23

based of their functions
Messenger RNA (mRNA); carries message from DNA
Transfer RNA (tRNA); brings amino acids to ribosome
Ribosomal RNA (rRNA); part of the ribosome

Question 24

what is a Transcription event

Answer 24

production of RNA based off a DNA template

Question 25

What is RNA-polmerase

Answer 25

An enzyme which binds to the DNA and finds a promoter

Question 26

What is a Promoter that is found by RNA-polimerase

Answer 26

tells the enzyme that this is the start of a gene and where transcription should begin

Question 27

What is a stop site found by RNA-polimerase

Answer 27

Signals the end of a gene and where transcription should end

Question 28

What are introns

Answer 28

Part of RNA which are not expressed in the protein and need to be removed thro RNA splicing before translation

Question 29

What are Exons

Answer 29

Part of the RNA which holds the coding regions for proteins

Question 30

Where does a codon on mRNA pair

Answer 30

it pairs with the anitcodon on tRNA and determines which amino acid is attached to the peptide chain

Question 31

How many different codons can there be

Answer 31

64; with a 3 nucleotide code and 4 nucleotide bases

Question 32

How many amino acids are there

Answer 32

20; meaning multiple codons can code for the same amino acid

Question 33

what is degeneracy

Answer 33

Its demonstrates that with the 20 amino acids, means multiple codons can code for the same AA

Question 34

What is an operon

Answer 34

a cluster of genes with related functions acting as a coordinated unit and controlled by a regulatory sequence

Question 35

What are the components that comprise the operon

Answer 35

1. structural genes
2. promoter
3. repressor
4. activator
5. operator

Question 36

What are the structural genes in the operon for

Answer 36

code for proteins

Question 37

what is the promoter in the operon

Answer 37

a region that influences the efficiency of gene transcription (enzymes recognizes where transcription should begin)

Question 38

what is the repressor of the operon

Answer 38

a gene that codes for a protein which inhibits transcription of a specific gene of the operon when bound to DNA

Question 39

what is a activator in the operon

Answer 39

a gene that codes for a protein which enhances transcription of a specific gene of the operon when bound to DNA

Question 40

what is a operator in the operon

Answer 40

a sequence of DNA which can bind a repressor and/or an activator protein (controls when it can and can not transcript, an on off switch)