DNA Test

Question 1

What does DNA stand for?

Answer 1

Deoxyribonucleic

Question 2

What are the 2 reasons why DNA is unique?

Answer 2

Contains our genetic information
Copies itself and replicates it exactly

Question 3

What are the building blocks (monomers) of DNA?

Answer 3

Nucleotides

Question 4

What are the 3 parts of a nucleotide?

Answer 4

5 carbon sugar; deoxyribose
Phosphate group or PO4
Nitrogen base

Question 5

What are the 4 nitrogen bases present in DNA?

Answer 5

Adenine, Guanine, Thymine, Cytosine

Question 6

What are purines? How many rings do they have?

Answer 6

Adenine & Guanine; 2 rings

Question 7

What are pyrimidines? How many rings do they have?

Answer 7

Thymine & Cytosine; 1 ring

Question 8

The double helix structure of DNA was discovered by 4 scientists - what are their names and what was the year?

Answer 8

James Waston, Francis Crick, Rosalind Franklin, Maurice Wilkins; 1953

Question 9

What did Erwin Chargaff discover?

Answer 9

That the percentage of G and C are almost equal as are A and T

Question 10

What is the “backbone” of DNA made up of?

Answer 10

Phosphate group & deoxyribose

Question 11

What holds the DNA molecule together?

Answer 11

Hydrogen Bonds

Question 12

The nitrogen bases are always connected to the (sugar or phosphate)?

Answer 12

Sugar

Question 13

Name the complementary strands of a DNA molecule.

Answer 13

mRNA

Question 14

What enzyme “unzips” the 2 strands of DNA in DNA replication?

Answer 14

DNA Helicase

Question 15

What does DNA polymerase do?

Answer 15

Joins individual nucleotides to produce the new DNA molecule, also proofreads each new DNA strand, helping maximize the odds that each molecule is perfect copy of the original DNA strand

Question 16

If one strand of DNA if ATT CCG, what is the other complementary strand of DNA?

Answer 16

TAA, GGC

Question 17

What are the 3 types of RNA? What does each type do?

Answer 17

Messenger RNA; Carries Genetic information
Transfer RNA; Translate mRNA into proteins
Ribosomal RNA; Forms Ribosomes

Question 18

What are 4 differences between RNA and DNA?

Answer 18

DNA; 2 strands, sugar is deoxyribose, Nitrogen bases T, C, G, A, Stays in the nucleus
RNA; 1 strand, sugar is ribose, Nitrogen bases A, U, C, G, leaves the nucleus

Question 19

What is transcription? Where does it occur in the cell (nucleus or cytoplasm)?

Answer 19

RNA molecules are produced by copying part of the nucleotides sequence of DNA into a complementary sequence in RNA; happens in the nucleus

Question 20

Briefly describe the steps of transcription.

Answer 20

RNA polymerase binds to a specific DNA molecule the promoter site, which has specific base sequences. Promoters are signals in DNA that indicate to the enzyme where to connect to make RNA
Separation of the complementary DNA strands
RNA polymerase then uses one strand of DNA as a template from which nucleotides are assembled into a strand of RNA
RNA polymerase reaches the termination site, and newly made RNA is released
RNA moves into the cytoplasm through the Nuclear Pores. There it will be read by a ribosome to make proteins

Question 21

What enzyme is responsible for transcription?

Answer 21

RNA polymerase

Question 22

How does mRNA move from the nucleus to the cytoplasm of a cell?

Answer 22

Through nuclear pores

Question 23

If an RNA molecule contains the sequence AAC GCU, what is the sequence of the DNA molecules from which it was made?

Answer 23

TTG, CGA

Question 24

A series of 3 mRNA nitrogen bases that contains the information needed to make proteins are called what?

Answer 24

Codons

Question 25

What is the universal start codon and what amino acid does it code for?

Answer 25

AUG; Methionine

Question 26

What are the 3 stop codons?

Answer 26

UGA, UAA, UAG

Question 27

What is translation? Where does it occur in the cell (nucleus or cytoplasm)?

Answer 27

The sequence of nitrogenous bases (A, U, C, G) in the newly made mRNA strand is translated into a chain of amino acids (PROTEINS) in the cytoplasm at the ribosome.

Question 28

Find the mRNA strand, tRNA anticodon and amino acid sequence for the following DNA strand: TAC CCT CAT ACT

Answer 28

mRNA: AUG GGA GUA UGA tRNA: UAC CCU CAU ACU

Question 29

briefly describe the process of translation.

Answer 29

mRNA made a copy of DNA, and enters the cytoplasm through the nuclear pores tRNA picks up specific amino acids in the cytoplasm, and transports them to the ribosome When a tRNA anticodon connects to the mRNA codon, the amino acid detaches and connects to the growing chain of proteins via peptide bond tRNA detaches from mRNA and is free to go pick up new amino acids, and the mRNA strand disintegrates

Question 30

What does the word “mutation” mean?

Answer 30

Any change in a DNA strand

Question 31

Mutations that produce changes in a single gene are called?

Answer 31

Point Mutation

Question 32

Mutations that produce changes in whole chromosomes are known as?

Answer 32

Chromosomal Mutations

Question 33

In what way(s), if any, do most mutations change organisms?

Answer 33

Most are neutral, but some are harmful/helpful,

Question 34

What are the 3 examples of gene (point) mutations?

Answer 34

Silent mutations, Missense mutations, Nonsense mutations

Question 35

Insertions and deletions usually result in frameshift mutations. What does this mean?

Answer 35

Its shifts the reading frame resulting in every amino acid to change

Question 36

What are the 4 examples of chromosomal mutations? Explain each.

Answer 36

Deletion, Duplication, Inversion, Translocation