Lecture 1

Question 1

What are the three components of DNA nucleotide?

Answer 1

1) phosphate group (-)
2) Deoxyribose (5 carbon- sugar)
3) Nitrogenous base (A,T,C,G)

Question 2

What is the name of the bond that joins one nucleotide to another in a DNA strand?

Answer 2

phosphodiester bond (covalent)

Question 3

Which chemical groups of nucleotides react to form a phosphodiester bond?

Answer 3

The phosphate of one nucleotide (attached to the 5’ end) and the hydroxyl group (OH) of another is added to the 3’ end.

Question 4

What are the names of the four bases? (5 with RNA?)

Answer 4

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

Question 5

What enzymes catalyzes phosphodiester bonding?

Answer 5

DNA polymerase

Question 6

What bond joins one strand of a DNA duplex to another?

Answer 6

Hydrogen bonds (weak bonds)

Question 7

What term is used to describe the pattern of base pairing between one DNA strand and its partner in a duplex?

Answer 7

complimentary

Question 8

What term is used to describe the polarity of two DNA strands?

Answer 8

antiparallel

Question 9

How many phosphodiester bonds are in a sequence?

Answer 9

2n-2
n=number of nucleotides/bases

Question 10

How many hydrogen bonds are in a sequence?

Answer 10

A:T=2x #A/Ts
C:G=3x # C/Gs

Question 11

Define semiconservative replication.

Answer 11

Daughter strands contain one OG and one new strand of DNA. CORRECT THEORY.

Question 12

Define conservative replication.

Answer 12

One daughter is 2 new, the other 2 OG.

Question 13

Define dispersive DNA replication.

Answer 13

Each daughter is a mix of new and OG

Question 14

What the 3 steps of PCR reaction?

Answer 14

1) Denaturation (95ºC)- break H-bonds
2) Primer annealing- reaction is cooled to allow primers to attach to a target region
3) Primer extension: temperature is raised to allow TAQ POLYMERASE (heat stabile DNA polymerase)

Question 15

What is a dideoxynucleotide triphosphate (Sanger Sequencing)?

Answer 15

-Chain-terminating Sequencing using ddNTPs (dud bases that stop transcription because they are MISSING THE HYDROXYL GROUP)
-5%, 95% regular bases (dNTPs)
-fluorescence–> corresponding base color–> read sequence

Question 16

What is gel electrophoresis?

Answer 16

separates molecules based on size (smallest travels the farthest)
-DNA has - charge, so travels from - wells to + charged end

Question 17

What direction are gel electrophoresis read?

Answer 17

5’ end/ + end (bottom to top), from small to large

Question 18

How has next generation sequencing (NGS) affected the price of sequencing the human genome?

Answer 18

Allows for hundreds of thousands of sequences to be sequenced simultaneously–> cheaper

Question 19

Define “massively parallel sequencing”

Answer 19

NGS methods where hundreds of thousands of DNA fragments are sequenced simultaneously

Question 20

What characterizes Huntington disease’s genotype?

Answer 20

Increased CAG repeats (CAG’s read higher than normal on gel graph)