18.1- DNA structure and replication

Question 1

DNA controls ____

Answer 1

heredity

Question 2

Hereditary info is carried through ___ on ____

Answer 2

genes on chromosomes

Question 3

how Is cell structure and function controlled

Answer 3

through DNA controlling protein synthesis

Question 4

RNA is involved in

Answer 4

gene expression

Question 5

who came up with the transforming principle

Answer 5

Frederick griffith

Question 6

what was the transforming principle

Answer 6

dead pathologic bacteria could pass on the disease causing capabilities to live bacteria- live bacteria- were “trasnformed”

Question 7

what did Hershey and chase use

Answer 7

they used radioactive labeling to trace hereditary material of a virus

Question 8

Both DNA and RNA are made up of small subunits called ___

Answer 8

nucleotides

Question 9

DNA bases =

Answer 9

Adenine (A)
guanine (G)
Cytosine (C)
Thymine (T)

Question 10

RNA bases =

Answer 10

Adenine (A)
guanine (G)
Cytosine (C)
Uracil (U)

Question 11

A + G are called ___

Answer 11

Purines

Question 12

C + T/U are called ___

Answer 12

pyridamines

Question 13

What is chargaffs rule

Answer 13

A pairs with T
C pairs with G
(Purines pair with pyridamines)

Question 14

what did Rosalind Franklin do/discover (2)

Answer 14

• Used x-rays to study the shape of DNA
• Discovered that DNA has a helical structure with sugar phosphate backbone on the outside and bases on the inside

Question 15

what did Watsin and Crick do

Answer 15

• produced a model of DNA structure

Question 16

describe the double helix structure of DNA

Answer 16

2 nucleotide strands (connected by H-bonds) twisted into a helical shape

Question 17

Nucleotide strands are ___ to each other

Answer 17

antiparallel (flipped)

Question 18

Genome=

Answer 18

The entire set of DNA found in each cell

Question 19

Genetic code is made up of ___

Answer 19

a specific sequence of nucleotides

Question 20

DNA can make exact copies of itself during what phase

Answer 20

The S phase of interphase

Question 21

what is the S phase

Answer 21

DNA synthesis (copy)

Question 22

3 stages of DNA replication

Answer 22

1- Initiation
2- Elongation
3- termination

Question 23

what happens during the initiation stage of DNA replication (3)

Answer 23

• begins at replication fork
• Helicase enzymes bind to replication origin and cause DNA to unwind/unzip
• unzipped strands act as templates for new strands to build from

Question 24

what happens during the elongation stage of DNA replication (4)

Answer 24

• Enzyme DNA polymerase nucleotides are added to 3’ end of chain
• leading strand is replicated continuously from 5’ end to 3’ end
• lagging strand is replicated in many short segments (okazaki fragments)
• newly replicated segments return to double helix

Question 25

what happens during the termination stage of DNA replication (1)

Answer 25

when both strands of DNA are completely replicated they separate and the replication machine breaks down

Question 26

what makes up the replication machine

Answer 26

many enzymes and proteins involved in the replication fork

Question 27

what enzymes cause DNA to unwind/unzip

Answer 27

Helicase

Question 28

What does DNA Ligase do

Answer 28

links okazaki fragments together into a continuous chain

Question 29

what provides a starting point for DNA polymerase

Answer 29

RNA primer

Question 30

What does DNA polymerase do and what stage of DNA replication is it involved in

Answer 30

• It proofreads to sequence and makes sure H-bonding is happening between complementary bases
• Elongation stage

Question 31

What Sugar does DNA use

Answer 31

deoxyribose

Question 32

what Sugar does RNA use

Answer 32

Ribose

Question 33

RNA uses ___ instead of thymine as a _____ base

Answer 33

Uracil
nitrogenous base

Question 34

is RNA single stranded or double stranded

Answer 34

Single stranded