Unit 10: mutations and cancer

Question 1

the central dogma of biology

Answer 1

DNA is transcribed into RNA which is translated into protein

Question 2

Transcription

Answer 2

A process in which RNA polymerase copies a gene and builds mRNA
Happens inside the nucleus.

Question 3

Translation

Answer 3

A process in which the ribosome uses the mRNA to build a protein.
Takes place in the cytoplasm.

Question 4

Gene

Answer 4

a piece of DNA which codes for a protein

Question 5

codon

Answer 5

three mRNA bases

Question 6

anticodon

Answer 6

three tRNA bases which will pair with the codon

Question 7

mRNA

Answer 7

an RNA copy of a gene
built in the nucleus, translated in the cytoplasm
“messenger” RNA because it carries information

Question 8

tRNA

Answer 8

a folded RNA molecule which carries an amino acid
The ribosome checks to see if the mRNA codon matches the tRNA anticodon; if so, the tRNA’s amino acid is moved onto the chain.
“transfer” RNA because it carries the amino acid.

Question 9

Ribosome

Answer 9

A cellular structure which “reads” the mRNA and builds the protein (or amino acid sequence).

Question 10

RNA

Answer 10

a nucleic acid
made of nucleotides
Uses U not T

Question 11

amino acid

Answer 11

the subunit of a protein

carried by the tRNA

Question 12

template strand

Answer 12

the strand of DNA which is used to build the mRNA

Question 13

mutation

Answer 13

a change in the DNA

Question 14

mutant

Answer 14

an organism which has been changed because of DNA mutations

Question 15

mutagen

Answer 15

anything that causes mutations

Ex: UV radiation, X rays, gamma rays, smoke, pollutants

Question 16

Point mutation

Answer 16

a change in only one place in the DNA, causing only one amino acid to be affected.

Question 17

Silent mutation

Answer 17

A mutation which does not change the amino acid sequence

Question 18

Frameshift mutation

Answer 18

a deletion or insertion

changes the ribosome’s reading frame, causing a new series of triplets. Tends to produce a nonfunctional protein.

Question 19

stop codon

Answer 19

three mRNA bases which signal the ribosome to stop translation. Early stop codons cause proteins to be only partially built and probably useless.

Question 20

cancer

Answer 20

uncontrolled cell division, causing tumors

Caused by mutations in the DNA which give the cell abilities it wouldn’t normally have.

Question 21

Tumor suppressor proteins

Answer 21

proteins which stop the cell from dividing if the cell’s DNA has too many mutations.
If these proteins do not function correctly, the person is much more likely to get cancer.

Question 22

Tumor suppressor genes

Answer 22

the genes which code for tumor suppressor proteins.

Mutations to these genes mean the person is much more likely to get cancer.

Question 23

Which is more common, cancer from a gene that was inherited, cancer from pollution, or cancer from a person’s lifestyle?

Answer 23

Lifestyle. You can choose to live healthily and avoid most types of cancer.

Question 24

How are HELA cells (from Henrietta’s cancer) used today?

Answer 24

For laboratory research. They are a very common line of stem cells.

Question 25

If an mRNA strand is 33 bases long, how long will the protein be?

Answer 25

11 amino acids

Question 26

If a protein is 30 amino acids long, how long was the mRNA?

Answer 26

90 bases

Question 27

Put these in order from smallest to biggest: chromosome, genome, mRNA, anticodon, point mutation

Answer 27

point mutation, codon, mRNA, chromosome, genome