Chapter 11 - DNA

Question 0

11.1

Virus?

Answer 0

a package of nucleic acid wrapped in a protein coat

can reproduce by inserting genetic info into living cell

Question 1

11.1
explain what scientists conducted to determine that DNA carries genetic info? 
Griffith?
Avery?
Hershey and Chase?

Answer 1

Griffith - injected mice with harmless or harmful bacteria
Avery - concluded DNA was the transforming factor
Hershey and Chase - used viruses to confirm Avery’s conclusion with radioactivity

Question 2

11.1

Bacteriophage?

Answer 2

A virus that infects bacteria

Question 3

11.2

What is DNA?

Answer 3

Deoxyribonucleic Acid -

a molecule that stores genetic information.

Question 4

11.2

What is DNA made up of? What are it’s 3 parts?

Answer 4

DNA is made up of NUCLEOTIDES.

3 parts -

1. A sugar (deoxyribose)
2. A phosphate group
3. A nitrogenous base

Question 5

11.2

Nitrogenous Base?

Answer 5

a single or double ring of carbon and nitrogen atoms with functional groups.

Single Ring - pyrimidines

Double Ring - purines

Question 6

11.2

What is the shape structure of DNA?

Answer 6

a twisting shape, called a double helix.

two strands of DNA twist together with sugar phosphate backbone on the outside and nitrogenous base on inside

Question 7

11.2

Nitrogenous Base Pairs?

Answer 7

Pyrimidines Purines

Thymine ———–> Adenine

Cytosine ————> Guanine

Uracil —————> Adenine

Question 8

11.3

When is DNA copied? What is the process of copying the DNA molecule called?

Answer 8

DNA is copied before a cell divides.

DNA replication.

Question 9

11.3

What forms the bonds between the nucleotides of the new DNA strand?

Answer 9

DNA polymerases

Question 10

11.3

Steps of DNA replication?

Answer 10

1. Two strands of double helix separate
2. Uses each strand as pattern for making a complimentary strand.
3. Nucleotides line up
4. Enzymes link nucleotides together to form 2 new DNA strands called daughter cells.

Question 11

11.4

How did Beadle and Tatum study the relationship between genes and proteins?

Answer 11

“One Gene - One Enzyme” hypothesis, states each gene controls the production of specific enzyme.
(used bread mold)

Question 12

11.4

Transcription vs Translation?

Answer 12

Transcription : the DNA sequence is converted to a single stranded RNA molecule
(location : nucleus)

Translation : converts the nucleic acid sequence to an amino acid sequence
(location : cytoplasm)

Question 13

11.4

Codon?

Answer 13

a three base sequence that codes for one amino acid
(start codon and stop codon)

(words are to sentences as proteins are to amino acids)

Question 14

11.5

How many kinds of RNA are involved in making proteins?

Answer 14

Three (3)

Question 15

11.5
Messenger RNA
(mRNA)

Answer 15

RNA molecule that is transcribed from the DNA

DNA strand        ex : TAGCAAGCCT
       I
RNA transcript
       I
mRNA strand     ex : AUCGUUCGGA

Question 16

11.5

RNA polymerase?

Answer 16

joins the RNA nucleotides together during transcription

Question 17

11.5

Introns vs Exons?

Answer 17

Introns - part of RNA that does not code for amino acids

Exons - coding regions of RNA

Question 18

11.5
What happens to the RNA transcript before it is able to leave the nucleus?
What is this process called?

Answer 18

It is edited :
Introns are removed
Exons are put together

RNA SPLICING

Question 19

11.5
Transfer RNA
(tRNA)

Answer 19

a type of RNA that translates the codons of mRNA to the amino acids

(a molecule with an amino acid binding site at one end and a three base anticodon at the other end.)

Question 20

11.5
Ribosomal RNA
(rRNA)

Answer 20

type of RNA found in a ribosome

the tRNA anticodon binds to the mRNA codon to add the amino acid to the polypeptide

Question 21

11.6

what is a mutation? two types of mutations?

Answer 21

a change in the nucleotide sequence of DNA
includes..
substitutions - one nucleotide is replaced (small effect = one word changed in sentence)
insertions or deletions - one or more nucleotides are added to or removed from a gene (serious effects = change of whole sentence)

Question 22

11.6

What is a mutagen?

Answer 22

a physical or chemical agent that causes a mutation

Question 23

11.1

What carries out genetic information and is responsible for producing genetic info?

Answer 23

DNA

this was determined in the experiment of Chase and Hershey

Question 24

11.2

How are nucleotides joined to one another?

Answer 24

sugar - phosphate backbone

nitrogenous bases are attached to this backbone