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Flashcards in Chapter 6 Deck (52)
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1

Bonds joining one nucleotide to another are covalent________

Phosphodiester bonds

2

The ability of a substance to change the genetic characteristics of an organism

Transformation

3

Attachment of the base to the deoxyribose sugar, addition of phosphate.

Nucleotide

4

Adenine, guanine

Purines

5

Thymine, cytosine.

Pyrimidines

6

Spacing between repeating units along the axis of the helix is 3.4 Å, the helix undergoes one complete turn every 34 Å, the diameter of the molecule is 20 Å.

Measurements of DNA

7

Spiral to the right

B form DNA

8

Spirals to the left and the backbone takes on a zigzag shape

Z form DNA

9

Retroviruses

Use RNA as their genetic material

10

Number one) Ribose instead of deoxyribose. Number two) RNA contains the base uricil instead of thymine which pairs with adenine. Three) Most RNA molecules are single stranded

Differences between RNA and DNA

11

Copying in which one strand of each new double helix is conserved from the parent molecule and the other is newly synthesized.

Semi conservative replication

12

Know the Meselson – stall experiment

Semi conservative replication

13

The high energy phosphate bonds required to synthesize every DNA molecule consists of four

Deoxynucleotide triphosphates (DATP, DCTP, DGTP, DTTP)

14

Number one. The 4DNTP's Number two. The single-stranded template double-stranded DNA must be unwound. Number three. The primer with a free three prime hydroxyl group

Requirements for DNA replication

15

Proteins open up the double helix and prepare it for complementary base pairing

Initiation

16

Proteins connect the correct sequence of nucleotides on both newly formed DNA double helixes

Elongation

17

2 Y shaped areas

Replication forks

18

One newly synthesized strand that can grow continuously into each of the replication forks

Leading strand

19

Generated in pieces called OkaZaki fragments, The polarity of the _________ is opposite that the leading strand.

Lagging strand

20

Major role in producing the new strands of complementary DNA. Enzyme complex that adds nucleotides to the three prime end of a pre-existing strand of nucleic acid. Only functions in the five prime to three prime direction.

DNA polymerase III

21

Fills in the gaps between newly synthesized Okazaki fragments, replaces the RNA primer of the previously made Okazaki fragments with DNA

DNA polymerase I

22

Unwinds the double helix

DNA Helicase

23

Keep the DNA helix open

Single-stranded DNA binding proteins

24

Generates rna primers to initiate DNA synthesis. Attracts DNA polymerase III.

Primase

25

Welds together Okazaki fragments into a continuous strand of DNA

DNA ligase

26

Short sequence of nucleotides known as the…

Origin of replication

27

Initiator protein binds to the origin of replication. Initiator attracts DNA helicase. Replication bubble involves two replication forks. Single-strands will serve as templates for synthesizing new strands of DNA.

Initiation, preparing the double helix for use as a template

28

Linkage of subunits through the formation of phosphodiester bonds is known as polymerization. The DNA polymerase molecule actually moves along the anti-parallel template strand in the three prime to 5 prime direction.

Elongation: connecting the correct sequence of nucleotides to a continuous new strand of DNA

29

Initiated by short RNA primers

OKazaki fragment

30

DNA replication is generally…

Bidirectional