Module 3 Summary intro

Question 1

1. The process of STARTING DNA replication. Involves the ___ of the DOUBLE HELIX and the formation of a ___

Answer 1

Initiation

Unwinding

Replication bubble

Question 2

2. The process of ADDING nucleotides to the growing DNA strand, which is CATALYZED by DNA ___

Answer 2

Elongation

Polymerase Enzymes

Question 3

3. The process of ENDING DNA replication, which involves the completion of ___ and the ___ of the newly formed DNA molecules.

Answer 3

Termination

Replication

Separation

Question 4

Enzyme Involved in INITIATION (3)

Answer 4

SSB protein

Helicase

Topoisomerase

Question 5

Enzyme involved in ELONGATION

Answer 5

Primase

Ligase

DNA polymerase I

DNA polymerase III

Question 6

Formed when a SINGLE DNA strand INVADES the MAJOR of a DNA DUPLEX

Triple-stranded

HELICASE are favored in ___

The interactions between strands involves the ___ (the meaning of H) edge of the Watson-crick base pair of the duplex to form BASE TRIPLETS which explains its name.

Answer 6

H-DNA

Negatively super-coiled DNA

Hoogsteen

Question 7

Essential to several cellular processes including:

Recombination-dependent ___

Viral integration

Restarting of ___

Proper SEGREGATION of HOMOLOGOUS CHROMOSOME during meiosis

Essential inter-mediates in ___

Answer 7

HOLIDAY JUNCTION

DNA lesion repair

stalled replication forks

DOUBLE-STRAND BREAK REPAIR

Question 8

The FOUR-STRANDED structures assembled from ___ sequences

These structures found in ___ repeats (3’ overhangs at chromosome ends)

THese structures also found in CENTRAL REGIONS of the genome like in Centromeric sequences and in the IMMUNOGLOBULIN switch region.

Answer 8

G-Quadruplex

Guanine-rich

Telometric DNA

Question 9

( I refers to ___) also known as I form

DNA a TRANSITORY confirmation that can form in sequences rich in ___.

Held together in an ___ orientation by intercalated ___ base pairs.

Answer 9

I-motifs

intercalated

Cytosine

Antiparallel

cytosine-cytosine

Question 10

The BIOLOGICAL FUNCTIONS of DNA

Being the most underwound form of the double helix, it consequently serves as a SINK for the TORTIONAL TENSION (___) in NEGATIVELY Supercoiled DNA.

Z-DNA helps to maintain the gene close to it in its activated, NUCLEOSOME-FREE STATE

Z-forming sequences accumulate near the TRANSCRIPTION START SITE of genes in HUMANS and other EUKARYOTES

Suggested additional functions: (2)

Further functions can eb beneficial or deleterious to the cell

Answer 10

Superhelical tension

Z-DNA

RNA editing

Gene transactivation