Chapters 11-12

Question 1

Genes

Answer 1

any DNA sequence that is transcribed into RNA.

Question 2

DNA

Answer 2

Informational storage molecule.
Genome > chromosomes > genes > bases.
Double-stranded.

Question 3

RNA

Answer 3

Information transfer molecule.
Interacts with ribosomes to produce proteins.
Single-stranded.
3 types: mRNA, tRNA, and rRNA.

Question 4

Messenger RNA

Answer 4

Communicates a message from DNA to be converted into protein.
Linear sequence of RNA bases.

Question 5

Ribosomal RNA

Answer 5

Enzymatic RNA that binds amino acids together inside a ribosome.

Question 6

Transfer RNA

Answer 6

Brings amino acids to the ribosome and interacts with mRNA/rRNA.

Question 7

Codon

Answer 7

A 3 (nitrogenous) base group.

Question 8

Anticodon

Answer 8

A 3 base sequence of tRNA - comes with a particular amino acid.
Binds to the mRNA that is complementary.

Question 9

Process of Translation

Answer 9

Begins at a start codon and ends at a stop codon - mRNA needs a start codon to be translated.

1. mRNA enters the ribosome.
2. tRNA binds mRNA start codon creating codon/anticodon connection.
3. Another tRNA binds to the following codon.
4. rRNA created links between amino acids on those two tRNA molecules.
5. Polypeptide is synthesized.

Question 10

Mutations

Answer 10

A change in the base sequence of an organism’s DNA.
Can be beneficial and improve the efficiency of functionality of a protein, but most tend to be harmful.
Can be a change to a single base pair, or be larger scale.
Caused by errors in crossing over or chromosomal abnormality.

Question 11

Frameshift Mutations

Answer 11

May stop protein synthesis before it is complete or alter the identity of many amino acids in a protein.

Question 12

Substitution

Answer 12

One base is substituted for another DNA sequence.
Length of sequence stays the same.
Can result in amino acid changes or no amino acid changes at all.

Question 13

Insertions or Deletions

Answer 13

One or more base is added or removed.

Either of these will likely effect all codons following the mutation and can introduce premature stop codon.

Question 14

The Central Dogma in Eukaryotes

Answer 14

Transcription occurs in the nucleus.

Translation occurs in the cytoplasm/ER.

Question 15

The Central Dogma in Prokaryotes

Answer 15

Transcription and Translation both occur in the cytoplasm. This is why prokaryotes don’t undergo RNA splicing.

Question 16

How to control gene expression…

Answer 16

1. Modifying the promoter.

2. RNA splicing.

Question 17

Why is controlling gene expression important?

Answer 17

1. Prevents an organism from wasting energy and resources on protein production.
2. The environment is constantly changing and an organism must be able to react to that change.
3. Ensures that exactly the right proteins are available when they are needed.

Question 18

What molecules control inheritance?

Answer 18

1. Proteins.

2. DNA.

Question 19

DNA Base Pairing

Answer 19

C=G

A=T

Question 20

RNA Base Pairing

Answer 20

C=G

A=U

Question 21

RNA Polymerase

Answer 21

The key enzyme in the transcription of a gene.

Question 22

Process of Transcription

Answer 22

1. RNA Polymerase binds to a segment of DNA called a promoter.
2. The DNA begins to unwind.
3. RNA Polymerase matches RNA nucleotides to DNA nucleotides using base-pairing rules.
4. mRNA is produced.
5. RNA Polymerase reached a sequences of bases called a terminator.