Unit 4

Question 1

What are the differences between DNA and RNA

Answer 1

DNA
double helix
5c sugar- deoxyribose
Base: adenine, Guanine, Cytosine, Thymine

RNA
Single Helix
5c sugar- ribose
bases: adenine, guanine, cytosine, uracil

Question 2

What is the structure of DNA molecule called?

Answer 2

Deoxyribonucleic acid

Question 3

What is the structure of RNA molecule called?

Answer 3

ribonucleic acid

Question 4

What did johann Miescher contribute to the knowledge of DNA?

Answer 4

discovered in 1868 in pus from war bandages and in fish sperm. called it “nuclein”

Question 5

What did Robert Fuelgen contribute to the knowledge of DNA?

Answer 5

1914 devloped a stain for nuclein; stains chromatin red

Question 6

What did Fredrick Griffith contribute to the knowledge of DNA?

Answer 6

1928 worked with streptococcus pneumonia bacteria. Hypothesized that DNA was pathogenic- disease cause

Question 7

What did Oswald Avery contribute to the knowledge of DNA?

Answer 7

1944 used enzymes to destroy proteins and then DNA in bacteria.
Concluded that hereditary material was probably made of DNA and not protein

Question 8

What did Alfred Hershey and Martha Chase contribute to the knowledge of DNA?

Answer 8

Confirmed Avery conclusion. Proved that the genes were made of DNA, not protein

Question 9

What did Erwin Chargaff contribute to the knowledge of DNA?

Answer 9

1949 worked on DNA composition in USA
Concluded that a always equaled t and g= c
Also concluded that different species had different numbers of nucleotides, because they have different amounts of DNA nucleotide

Question 10

What did Maurice Wilkins and Rosalind Franklin contribute to the knowledge of DNA?

Answer 10

Both worked on the DNA structure
Franklin made the best x-ray diffraction of crystalline DNA, and worked out the dimensions of the molecule

Question 11

What did Watson and Crick contribute to the knowledge of DNA?

Answer 11

Bulit model of DNA in 1953
Used info of Franklin

Question 12

What was the purpose of project genome?

Answer 12

Decoding human DNA

Question 13

What contributions did center and collins make to project genome?

Answer 13

Used computers to speed gene sequencing

Question 14

What are the monomers of nucleic acids called?

Answer 14

Nucleotides

Question 15

Which subunits are the same in the nucleotides? Different?

Answer 15

3 subunits, the phosphate group and pentose sugar are same while nitrogen bases will be different

Question 16

What are the 2 purines? Describe them

Answer 16

Large, 2 carbon rings
Guanine
Adenine

Question 17

What are the 2 pyrimidines? Describe them

Answer 17

Small, 1 carbon ring
Cytosine
Thymine

Question 18

What scientist discovered the first enzyme associated with DNA Replication?

Answer 18

Arther kornberg, DNA Polymerase l

Question 19

What scientists proved that DNA replication was semi conservative?

Answer 19

Matthew meselson and Franklin stahl

Question 20

What does semi conservative replication mean?

Answer 20

Semiconservatie- one strand of DNA is made is made of original nucleotides and the complimentary strand of DNA is made of new nucleotides

Question 21

What is the function of helicase associated with DNA replication

Answer 21

Unwinds the double helix, creating a fork

Question 22

What is the function of polymerase lll associated with DNA replication

Answer 22

Add nucleotides to the leading strand- 5’3’ continuously

Question 23

What is the function of DNA polymerase l associated with DNA replication

Answer 23

Adds nucleotides in short sections called Okazaki fragments

Question 24

What is the function of ligase associated with DNA replication

Answer 24

Puts fragments together

Question 25

What is the function of “proof reading” enzymes associated with DNA replication

Answer 25

Proofing reading the nucleotides. 1 mistake/ 100,000,000 nucleotides

Question 26

What are the Okazaki fragments

Answer 26

The new DNA Strand forms in short fragments

Question 27

Which strand is the “leading” strand and is replicated continuously in DNA

Answer 27

5,3

Question 28

Which strand is the “lagging” strand and is replicated in fragments

Answer 28

3,5

Question 29

When does DNA replication occur

Answer 29

Occurs in interphase, just before prophase in mitosis

Question 30

What are mutations

Answer 30

A mistake that survives as a mutation. It usually changes gene. Can cause disease, improvement, or evolution

Question 31

What are the most common causes of mutations

Answer 31

Mutations can be produced by exposure to radiation, chemicals, and heat

Question 32

The theory of Enosymbiosis suggests that mitochondria and chlochloroplasts once lived lives as independent organisms. What do these organelles possess that makes them different from other organelles?

Answer 32

The ability to replicate

Question 33

What are most genes the formulas for

Answer 33

Proteins

Question 34

What are the general functions of proteins

Answer 34

Used to construct body tissue, enzymes, hormones, antibodies, and are a source of ATP

Question 35

What are the monomers of proteins

Answer 35

Amino acids

Question 36

How many amino acids are used by most organisms to build proteins

Answer 36

20

Question 37

What base is substituted for thymine in RNA

Answer 37

Uracil

Question 38

What type of rna is a complete copy or transcript of the DNA gene

Answer 38

MRNA

Question 39

What type of RNA carries amino acids from the cytoplasmic pool to the ribosome

Answer 39

tRNA

Question 40

What type of RNA combines with proteins to form the subunits of the ribosome

Answer 40

rRNA

Question 41

What type of RNA is built of codons

Answer 41

mRNA

Question 42

What are the 3 nucleotides in tRNA called

Answer 42

Anticodons

Question 43

How many different tRNA are made? Why?

Answer 43

20, one for each amino acid

Question 44

Which phase of protein synthesis occurs firsts?

Answer 44

Transcription

Question 45

Where does the first phase of protein synthesis occur

Answer 45

Occurs in nucleus

Question 46

Which strand of DNA is transcribed?

Answer 46

3’5’ strand

Question 47

What enzyme catalyzes transcription?

Answer 47

RNA Polymerase

Question 48

How does the enzyme in #16 know when to start and stop coding the gene?

Answer 48

With a start code and stop code

Question 49

What is the first transcript called?

Answer 49

Primary transcript

Question 50

What forms 2/3 of the primary transcript

Answer 50

Introns

Question 51

What are the functional parts of the transcript called

Answer 51

Extrons

Question 52

What are the non-functional parts of the transcript called?

Answer 52

Introns

Question 53

What removes the introns of the primary transcript

Answer 53

SnRPS - small Nuclear Ribonucleoprotein particles

Question 54

What is the “snRNP’d” mRNP called?

Answer 54

Functional or Mature RNA

Question 55

Where does the second phase of protein synthesis occur

Answer 55

Translation

Question 56

What is the second phase of protein synthesis called

Answer 56

Translation

Question 57

What are the sites in the ribosome called where peptide bonds are formed between amino acids

Answer 57

Accepter site and peptidal site

Question 58

What are polysomes

Answer 58

Many ribosome that attach to the mRNA and each translates the same strand of mRNA.

Question 59

Which occurs more often, protein synthesis or DNA replication

Answer 59

Protein synthesis

Question 60

What is the poison ricin extracted from and what is its effect?

Answer 60

Castor bean plant that removes an adenine base from rRNA in the large of the ribosome and shuts down protein synthesis

Question 61

What is the function of primase associated with DNA replication

Answer 61

Synthesize a short RNA Primer on the lagging strand 3’5’