Chapter 12 Molecule Biology Of The Gene

Question 0

Cells extracted treated with protease ( protein- digesting enzyme) or RNase ( RNA-digesting enzyme) retain transformation ability
Cells extracts treated with DNase ( DNA- digesting enzyme) lost their transforming ability

Answer 0

DNA is the transforming agent

Question 1

Hersey and Chase used bacteriophages to show that DNA not protein is the genetic material

Answer 1

Bacteriophages: are viruses that infect bacteria cells

Phases were labeled with radioactive sulfur to detect proteins or radioactive phosphorus to detect DNA

Question 2

DNA nucleotides

Answer 2

Nitrogenous base (A T G C )
5-carbon sugar ( deoxyribose)
Phosphate group

Question 3

Two nucleotides with purine bases ( two rings)

Answer 3

Adenine (A)

Guanine (G)

Question 4

Two nucleotides with pyrimidine bases (One ring )

Answer 4

Thymine (T)

Cytosine (C)

Question 5

Chargaff’s rules

Answer 5

The amount of ATGC are constant among member of same species
Vary from species to species

Question 6

Rosalind Franklin studies the structure of DNA using x-rays and produce an x- ray diffraction pattern

Answer 6

Evidence
DNA is a helix
Some portion of the helix is repeated

Question 7

The Watson and Crick model
DNA: sugar phosphate make up the sides
Hydrogen bonded bases make up the rungs keeping the two strands together

Answer 7

T

Question 8

DNA replication

Answer 8

Two identical copies

Question 9

Where does DNA replication take place?

Answer 9

Synthesis (S) phase of the cell cycle

Question 10

Watson and crick discovered what?

Answer 10

Specific pairings

Question 11

Semi conservative replication

Answer 11

Half parental. Half new

Question 12

Where does the DNA replication begin?

Answer 12

Origins of replication

Question 13

DNA helicase

Answer 13

Unwinds the double helix and breaks hydrogen bonds

Question 14

DNA polymerase

Answer 14

Adds nucleotides to a growing chain

Proofreads correcting mistakes

Question 15

DNA ligase

Answer 15

Joins small fragments of DNA into a continuous chain

Question 16

DNA replication occurs 5’ to 3’ direction

Answer 16

T

Question 17

Replication is continuous called

Answer 17

Leading strands

Question 18

Replication is discontinuous

Answer 18

Lagging strand

Question 19

In a eukaryotic cell :

Central dogma

Answer 19

The molecule chain of command
DNA in the nucleus is transcribed to mRNA
mRNA moves to the cytoplasm and translate to proteins

Question 20

Transcription

Answer 20

Is the synthesis of RNA under the direction of DNA it occurs in the nucleus

Question 21

Translation

Answer 21

Is the synthesis of proteins under the direction of RNA it occurs in the cytoplasm

Question 22

RNA is the polymer of RNA nucleotides

Answer 22

Single stranded
Contains sugar ribose , a phosphate group and a nitrogenous base
Four types : Uracil (U) C A G
Replaces T with U

Question 23

Messenger mRNA

Answer 23

Takes messages from DNA in the nucleus to ribosomes in the cytoplasm

Question 24

Ribosomal rRNA

Answer 24

Makes up ribosomes which read the message in mRNA

Question 25

Transfer tRNA

Answer 25

Transfers the appropriate amino acid to the ribosomes for protein synthesis

Question 26

An RNA molecule Is transcribed from a DNA template | Only one strand of DNA is used as a template and transcribed into single strands messenger RNA ( mRNA)

Answer 26

RNA nucleotides are linked together by the transcription enzyme RNA polymerase

Question 27

Addition of a 5' cap

Answer 27

5'cap help ribosomes bind to the mRNA

Question 28

Addition of a 3' poly A tail

Answer 28

Facilitates the export of the mRNA from nucleus | Protects the mRNA from attack by cellular enzymes

Question 29

RNA splicing

Answer 29

Removes introns and join exons to produce a continuous coding sequence in mature mRNA transcripts

Question 30

Continuous non overlapping triplet

Answer 30

Each triplet or codon codes for one amino acid

Question 31

Universal

Answer 31

All organism use same codons few exceptions

Question 32

Degenerate ( redundant )

Answer 32

Most amino acids are encoded by two or more codons

Question 33

Unambiguous ( codons are exclusive )

Answer 33

Each codon specifies only one amino acids

Question 34

Start codon

Answer 34

Signals the start of translation. | Codes for methionine- met

Question 35

Stop codons -UAA UGA UAG

Answer 35

do not code for amino acid | Signals the end or translation

Question 36

mRNA

Answer 36

Carries the message for protein synthesis

Question 37

tRNA

Answer 37

Serves as an interpreter between mRNA and protein transfer amino acids By picking up specific amino acids and anticodon Anticodons are complementary to codons in mRNA

Question 38

Ribosomes

Answer 38

Serves as manufacturing machine

Question 39

Amino acid

Answer 39

Monomer for proteins

Question 40

Each chromosome contains a single linear DNA molecule and protein

Answer 40

Histones responsible for packaging the DNA