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Flashcards in Sandy Chapter 13: RNA & DNA Deck (34):
1

Which three components go into making a nucleotide? 

Sugar

Base

Phosphate 

2

In the sugar-phosphate backbone of DNA: 

  1. Name the monosaccharide. 

  2. Name the four bases that are present.  

  3. Where are the bases attached? 

  4. What type of bond connects the sugar and the phosphate residues? 

  1. Deoxyribose
  2. Adenine, Guanine, Thymine, Cytosine
  3. At the anomeric carbon of deoxyribose 

  4. Phosphoester bonds

3

In the sugar-phosphate backbone of RNA:

  1. Name the monosaccharide. 

  2. Name the four bases that are present.

  3. Where are the bases attached?

  4. What type of bond connects the sugar and the phosphate residues? 

  1. ribose
  2. adenine, guanine, cytosine, uracil
  3. at the anomeric carbon of ribose
  4. phosphoester bonds

4

In terms of DNA and RNA structure, what do the terms 3’-terminus and 5’-terminus mean? 

3’ terminus: end of the nucleic acid that has the free hydroxyl functional group.

5’ terminus: end of the nucleic acid that has the free phosphate group

5

How does a single strand of DNA differ from a single strand of RNA? 

The sugar in the DNA is deoxyribose, the sugar in the RNA is ribose.

In RNA one of the bases present is Uracil. This base is absent in DNA and is replaced by thymine. 

6

Describe the primary structure of a DNA. 

The primary structure of the DNA is the sequence of its nucleotide residues

7

Describe the secondary structure of DNA. What are the complementary bases that hold the secondary structure together? What force holds double stranded DNA together? 

The secondary structure of the DNA is a double helix resembling a spiral staircase. The negatively charged phosphate groups are on the outside and the bases are on the inside

Adenine and thymine are complementary to each other Cytosine and guanine are complementary to each other 

Hydrogen bonding interactions. The two DNA strands are held to one another through base pairing, adenine is hydrogen bonded to thymine, cytosine is hydrogen bonded to guanine. 

8

  1. What are histones?
  2. What are nucleosomes?
  3. What is chromatin? 

  1. Histones are proteins which are rich in amino acids that contain the polar basic side chain.
  2. The DNA double helix is wrapped around a group of histones to form a nucleosome. 
  3. Chromatin is a coiled string of nucleosomes 

9

What is the interaction between DNA and histones? 

 

Salt bridges 

10

Amino acid side chains in histones must carry what net charge? 

Amino acid side chains in histones must carry a net positive charge.

Since histones are wrapped around with DNA which has the negatively charged phosphate groups on the outside, the interaction between the positively charged amino acid side chain and the negatively charged phosphate group is a happy ionic interaction. 

11

When DNA is denatured, which of the following is disrupted? 

The secondary structure of the DNA is disrupted during the process of denaturation. The double helix is disrupted. 

12

What molecule is made during the following processes? 

  1. DNA replication
  2. Transcription
  3. Translation
  4. reverse transcription 

  1. DNA
  2. mRNA
  3. proteins
  4. DNA

13

The primary structure of what molecule is read during the following processes? 

  1. DNA replication
  2. Transcription
  3. Translation
  4. reverse transcription 

 

  1. DNA
  2. DNA
  3. mRNA
  4. RNA

14

Name the substrates for DNA polymerase.

ATP

CTP

GTP

TTP

(A, C, G, T)

15

Name the substrates for RNA polymerase.

ATP

GTP

CTP

UTP

16

In addition to adding nucleotides to a growing DNA strand, what are other important functions of DNA polymerase? 

Proofread the newly synthesized DNA strand.

If errors are found in the DNA, the enzyme takes care of the repair of the DNA

17

Name the three types of RNA and describe their function. 

tRNA, mRNA and rRNA. 

tRNA: The function of tRNA is to bring the correct amino acid to the site of the protein synthesis.

mRNA: The strand of the mRNA contains the triplet codons which codes for the amino acids.

rRNA: The ribosomal RNA combines with proteins to form the multiunit complex in which the protein synthesis takes place. 

18

hat are codons? What type of nucleic acid has codons? 

Codons are a series of three bases in the mRNA that carry the code for protein synthesis

19

What are anticodons? What type of nucleic acid has anticodons? 

Antocodons are a series of three bases in the tRNA that are complementary to a codon. 

20

What types of post-transcriptional modifications do RNA’s undergo? 

Transfer RNA’s are shortened, some of the major bases are converted to minor bases, modifications to the mRNA involves altering the 3’ and 5’ ends and removing sections of mRNA whose code is not involved in translation. 

21

During the translation process, how many steps are involved? 

Name them.

Three steps are involved in the translation process.

 

They are initiation, elongation and termination.

Initiation: The ribosome, mRNA and tRNA come together to form a complex.
Elongation: Amino acids are joined to the growing polypeptide chain.

Termination: The protein has been synthesized. The complex consisting of mRNA, tRNA and the ribosome dissociates. 

22

Define the term mutation. 

Any permanent change in the primary structure of the DNA is called mutation.

23

Are all mutations harmful to an individual? Explain. 

Some amino acids have more than one codon. So minor mutations to a gene may not be harmful since the correct amino acid is incorporated into the protein structure. 

24

Are all mutations passed on to offspring? Explain. 

Those mutations that take place in an egg or sperm cell can be inherited. 

25

Which reaction is catalyzed by RNA polymerase?

What is the name of this process?

Addition of nucleotide residues to a growing RNA strand. 

Transcription 

26

Which building blocks are used to form the final product of transcription? 

Ribonucleotides 

27

What has to happen to the DNA double helix before RNA polymerase can catalyze the transcription reaction? 

the two strands of the DNA have to seperate

28

What is the name of the DNA strand that gets read by RNA polymerase?

Template strand 

29

In which direction does RNA polymerase move along the DNA?

3' to 5'

30

To which end of the growing product chain are building blocks attached? 

3'

31

Which monosaccharide is used to make DNA?

2-Deoxyribose 

32

Name the four bases that are present in DNA.

  1. Cytosine
  2. Guanine
  3. Thymine
  4. Adenine

33

Which of the bases present in nucleotides are purines?

Adenine 

Guanine 

34

The structure of phosphoric acid is pH dependant. 

Which forms appear at physiological pH?

Dihydrogenphosphate ion 

Hydrogenphosphate ion