1. Nucleic Acid Structure and Organization

Question 1

DNA replication is..

Answer 1

The process in which each chromosome is duplicated before cell division

Question 2

Where and when does transcription occur?

Answer 2

In the nucleus, throughout interphase

Question 3

Where and when does translation of RNA occur?

Answer 3

In the cytoplasm, throughout the cell cycle

Question 4

When and where does DNA replication occur?

Answer 4

In the nucleus, during S phase

Question 5

What is M phase?

Answer 5

Mitosis, cell divides to form two daughter cells

Question 6

What is interphase?

Answer 6

Time between two cell divisions/mitoses

Question 7

When are genes expressed?

Answer 7

Throughout interphase

Question 8

Phases of interphase are..

Answer 8

G1, S and G2

Question 9

G1 phase is..

Answer 9

Period of cellular growth preceding DNA synthesis

Question 10

G0 phase is..

Answer 10

Cells that have stopped cycling

Question 11

S phase is..

Answer 11

DNA replication, leading to two identical chromatids

Question 12

G2 phase is..

Answer 12

Period of cellular growth after DNA replication but preceding mitosis. Checked for errors.

Question 13

S-phase chemotherapeutics

Answer 13

Methotrexate, r-fluorouracil, hydroxyurea

Question 14

G2-phase chemotherapeutics

Answer 14

Bleomycin

Question 15

M-phase chemotherapeutics

Answer 15

Paclitaxel, vincristine, vinblastine

Question 16

Non cell-cycle specific chemotherapeutics

Answer 16

Cyclophosphamide, cisplatin

Question 17

Checkpoints

Answer 17

Cyclins and cyclin-dependent kinases

Question 18

Nucleotide components

Answer 18

Nitrogenous base, five-carbon sugar (pentose) and phosphate

Question 19

Purines

Answer 19

Contain two rings. Adenine, guanine. (others: xanthine, hypoxanthine, uric acid)

Question 20

Pyrimidines

Answer 20

Contain one ring. Cytosine, uracil, thymine

Question 21

Nucleoside

Answer 21

Base added to number 1 carbon of sugar

Question 22

Nucleotide

Answer 22

Nuclease + phosphate(s) to 5’ carbon

Question 23

Difference ribose and deoxyribose

Answer 23

Ribose has OH group at 2’ carbon of the sugar, deoxyribose has H.

Question 24

Nomenclature Base, Nucleoside, Nucleotide

Answer 24

Adenine-Adenosine-AMP
Guanine-Guanosine-GMP
Cytosine-Cytidine-CMP
Uracil-Uridine-UMP
Thymine-Deoxythymidine-dTMP

Question 25

Nucleic acids

Answer 25

Linked by 3’,5’ phosphodiester bonds
Have distinct 3’ and 5’ ends, thus polarity
Sequence always specified as 5’->3’

Question 26

Chargaff’s Rules

Answer 26

%A = %T, %G = %C

% purines = % pyrimidines

Question 27

DNA molecule

Answer 27

Mostly Watson-Crick DNA or B-DNA, right handed, 10 bps per complete turn of helix.
Left-handed rare in G-C rich sequences, Z-DNA.

Question 28

Daunorubicin and doxorubicin

Answer 28

Exert their effects by intercalating between bases of DNA, interfering with topoisomerase II and preventing proper replication of DNA.

Question 29

Cisplatin

Answer 29

Binds tightly to DNA, causing structural distortion and malfunction

Question 30

Denaturation

Answer 30

Disrupt hydrogen bonding and base stacking

Heat, alkaline pH, chemicals (form amide, urea)

Question 31

Supercoiling

Answer 31

Negative: more loosely wound (biological reactions)
Positive: more tightly
-> Topoisomerase, makes transient breaks

Question 32

Histones are rich in

Answer 32

Lysine and arginine (positive charge)

Question 33

Histone octamer

Answer 33

Two copies of each H2A, H2B, H3 and H4 aggregate

Question 34

Nucleosome

Answer 34

DNA winds around outside of histone octamer

AKA beads on a string, 10nm chromatin fiber

Question 35

Nucleofilament

Answer 35

H1 associates with nucleosome, 30nm fiber

Question 36

Karyotype analysis uses..

Answer 36

Metaphase chromosomes, highly condensed

Question 37

Banding techniques use..

Answer 37

Prophase or pro metaphase chromosomes