Dna, Rna and protein synthesis unit #1

Question 1

What does DNA stand for

Answer 1

DNA stands for deoxyribonucleic (dee-OK-see-ri-bo-new-klee-ik) acid. It is the genetic information inside the cells of the body that helps make people who they are.

Question 2

Two reasons why DNA is unique

Answer 2

-To store and use info to direct activities of cells
- to copy itself exactly

Question 3

building blocks of DNA (monomers)

Answer 3

nucleotides

Question 4

3 parts of a nucleotide?

Answer 4

1, deoxyribose
2. phosphate
3. nitrogen base

Question 5

what are the 4 nitrogen bases in DNA?

Answer 5

Adenine + Guanine
Thymine + Cytosine

Question 6

What are pyrimidines? How many rings do they have?

Answer 6

Thymine + Cytosine, Single ringed structures

Question 7

what are Urines? how many rings do they have?

Answer 7

Adenine + Guanine, double-ringed structures

Question 8

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

Answer 8

• Erwin Chargaff 1949
• Rosalina Franklin 1953
• Watson 1953
• Crick 1953

Question 9

What did Erwin Chargaff discover?

Answer 9

Erwin Chargaff found that in DNA, the ratios of adenine (A) to thymine (T) and guanine (G) to cytosine (C) are equal.

Question 10

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

Answer 10

DNA Helicase

Question 11

DNA polymerase what does it do?

Answer 11

Hydrogen bonds link those complements to the “old” strand of DNA with the help of this enzyme

Question 12

What is the “Backbone” of DNA made up of

Answer 12

Sugar?phosphate

Question 13

What are the 3 types of RNA?

Answer 13

• Messenger RNA (mRNA)
• Transfer RNA (tRNA)
  -Ribosomal RNA (rRNA)

Question 14

Messanger RNA function

Answer 14

Found in nucleus, then moves to cytoplasm through nuclear pores single, uncoiled chain: carries genetic info of DNA in the nucleus to the cytoplasm

Question 15

Transfer RNA

Answer 15

Found in cytoplasm bonds to a specific amino acid and carries the amino acid to ribosomes

Question 16

Ribosomal RNA

Answer 16

Found in ribosomes RNA functions in the ribosomes as a metabolic molecule that aids in protein sythesis

Question 16

Steps of Transcription?

Answer 16

1. An enzyme called RNA polymerase binds to a specific region in DNA molecule called the promoter site. promoter sites have specific base sequences. promoters are signals in DNA that indicates to the enzyme where binds to RNA.
2. seperation of complementery strands of DNA occurs
3. RNA polymerase than uses one strand of DNA as a template from which nucleotides are assembled into a strand of RNA
4. polymerase reaches the termination site, and the newly made Rna released
5. The New RNA strand moves from the nucleus to the cytoplasm through the nucleus pores

Question 17

Transcription takes place in the…

Answer 17

Cytoplasm. it will be read by a ribosome to make a protein. protein synthesis is important because proteins play roles in enzymatic action, transport, motion, protection, support, communication and regulation.

Question 18

4 Differences between DNA and RNA

Answer 18

of strands present: DNA: 2, RNA: 1
Name of 5- carbon sugar: DNA: Deoxyribose, RNA: Ribose
Nitrogen bases: DNA: AT CG, RNA: AU CG
DNA long term, RNA is temporary

Question 19

what holds DnA molecules together?

Answer 19

Hydrogen Bonds

Question 20

Nitrogen bases are always connected to the?

Answer 20

Sugar molecule

Question 21

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

Answer 21

through pores in the nuclear membrane.

Question 22

What are introns and exons

Question 23

What are the 3 nitrogen bases on mRNA called?

Answer 23

The bases in mRNA are grouped into sets of three called codons.

Question 24

what is the universal start codon

Answer 24

AUG, encodes the amino acid methionine

Question 25

3 stop codons

Answer 25

3 are stop codons (i.e., UAA, UAG and UGA

Question 26

Translation takes place in? what is it?

Answer 26

in Cytoplasm, proteins are produced using RNA molecules as templates. The generated protein is a sequence of amino acids.

Question 27

What is Mutation?

Answer 27

Any change in DNA sequence of a cell

Question 28

Mutations that produce changes in a single gene are called

Answer 28

point mutations

Question 29

Mutations that create changes in a whole chromosome are known as

Answer 29

chromosomal mutations

Question 30

In what ways do mutations change organisms

Answer 30

harm an organism’s ability to survive and reproduce.

Question 31

what are the 3 examples of gene (point) mutations

Answer 31

Base substitutions are point mutations where one base is swapped for another. Insertions are point mutations where one or a few bases are added at one location in a DNA sequence. Deletions are point mutations where one or a few bases are removed from one location of a DNA sequence.

Question 32

nsertion and deletions usally result in framshift mutations?

Answer 32

it alters the reading frame and completely changes the amino acid sequence

Question 33

4 examples of chromosomal mutation?

Answer 33

deletion, duplication, inversion, and translocation ( explain each)