2.4 - How is the CFTR protein made?

Question 1

Define mutation.

Answer 1

change in the genetic material in a cell.

Question 2

What is a small change to an organism’s DNA called?

Answer 2

gene mutation

Question 2

What can increase the chance of mutations?

Answer 2

environmental factors called mutagens

Question 3

Define gene.

Answer 3

a sequence of nucleotides in DNA which code for a sequence of amino acids

Question 4

What are the different forms of genes called?

Answer 4

alleles

Question 4

What does each gene code for?

Answer 4

specific protein

Question 5

How do alleles differ from each other?

Answer 5

in the sequences of their nucleotide

Question 6

What is the result of difference in allele in the sequences of nucleotide?

Answer 6

makes a slightly diff. protein

Question 7

Define genome.

Answer 7

• all DNA inside a cell
• genome contains full set of genes controlling growth & development of the organism of which the cell is a part

Question 8

What is DNA biologically?

Answer 8

deoxyribose nucleic acid forms the genetic material of all living orgnsms.

Question 9

What is DNA made up of?

Answer 9

2 polynucleotide chains forming a double helix.
each chain consist of a sugar-phosphate backbone

Question 10

Define nucleotide.

Answer 10

made up of a pentose sugar
(ribose (RNA) or deoxyribose (DNA)), phosphate group & a nitrogenous base

Question 11

How many hydrogen bonds are there between thymine and adenine base pairs?

Answer 11

2 hydrogen bonds

Question 12

How many hydrogen bonds are there between cytosine and guanine base pairs?

Answer 12

3 hydrogen bonds

Question 13

Describe how nucleotides join together to form DNA.

Answer 13

• condensation reaction takes place
• DNA polymerase catalyses reaction
• phosphodiester bond forms between 2 mononucleotides

Question 14

DNA codes for what?

Answer 14

protein

Question 15

How many bases code for one amino acid? What is this called?

Answer 15

3 - triplet codon

Question 16

What 3 terms could you use to describe the genetic code?

Answer 16

1. triplet (code)
2. non-overlapping
3. degenerate

Question 17

Define non-overlapping.

Answer 17

each DNA triplet code is adjacent

Question 18

Define degenerate.

Answer 18

there are more codons than there are aminos acids, becaue triplets can code for the same amino acid

Question 19

Define transcription.

Answer 19

the process by which a DNA sequence is copied into an RNA sequence by the enzyme RNA

Question 20

Define protein synthesis.

Answer 20

making of proteins

Question 21

Define translation.

Answer 21

process by which genetic info stored in RNA is translated into a sequence of amino acids to form a protein

Question 22

What is a codon?

Answer 22

3 mRNA bases that code for an amino acid

Question 23

What is mRNA?

Answer 23

single stranded nucleic acid

Question 24

What is RNA polymerase?

Answer 24

enzyme that causes the DNA strand to unwind in transcription

Question 25

What is a template strand?

Answer 25

the DNA strand that mRNA attaches to in transcription

Question 26

Why does Meselson & Stahl’s experiment mean that they accepted one model of DNA and not the other?

Answer 26

• generation 1 has a single band halfway btwn 15N & 14N
• because DNA has one strand containing 15N & one strand containing 14N
  thus DNA replication is semi-conservative