Ch. 16 How Genes Work

Question 1

Note the differences between DNA replication and

Answer 1

DNA replication is the process by which a DNA molecule is copied, while transcription and translation are the processes by which RNA molecules and proteins, respectively, are synthesized using the information in the DNA molecule

Question 2

Central Dogma

Answer 2

genetic information is transferred from DNA to RNA to protein, in a unidirectional manner

Protein synthesis takes place in the cytoplasm; Carries codes from the DNA in the nucleus to the sites of protein synthesis in the cytoplasm(ribosomes)

Genetic code links groups of nucleotides in an mRNA to amino acids in a protein (start codons, stop codons, reading frame)

Question 3

Role of Transcription

Answer 3

process of using A DNA template to make a complementary RNA; Making a copy of information

begins in nucleus and then leaves to cytoplasm, Template is what leaves the nucleus

Antiparallel orientation creating mRNA(similar to DNA polymerase but CHEMICALLY DIFFERENT)

Base pairs are used to create a DNA match

NOTE: mRNA uses uracil( paired with adenine) instead of thymine

Question 4

Template Strand

Answer 4

Strand of DNA that is “read” and/ or referenced to create another strand of mRNA later on

3’ to 5’

Question 5

Coding Strand

Answer 5

NONTEMPLATE STRAND, the strand that is written

5’ to 3’

Question 6

Translation

Answer 6

process of using information in mRNA to synthesize proteins; Interprets nucleotide “language” to amino acids, Info from mRNA makes proteins (Ribosome found and mRNA attaches to it, creates Protein strand)

occurs in the cytoplasm

Question 7

How to read genetic code

Answer 7

o Single bases are coded in pairs of three to provide up to 64 amino acids available to create genetic code(more than enough)
o Adenine, Thymine/Uracil, Guanine, Cytosine

Question 8

How to use Codons of genetic code(chart)

Answer 8

Find the first base starting from the left side, find the second base from the top, and then find the box that correlates to those; then find the third base you need in that box to find the appropriate amino acid

Question 9

DNA vs mRNA base pairs

Answer 9

DNA includes thymine (template strand)

RNA includes Uracil, being written/coded(coding/nontemplate strand)

Question 10

Explain the overall process of this chapter

Answer 10

• A non-template strand and template strand are attached to each other
• A template strand is separate and is taken from the Central Dogma, from the DNA sequence in the nucleus, and taken into the cytoplasm
• The template strand(DNA) would aid transcription and making a complimentary strand of mRNA in the cytoplasm
  o Read 3’ to 5’ from template strand, written 5’ to 3’ for coding/non-template strand
• DNA triplets(3-sectioned base pairs) will yield 3-sectioned pairs of mRNA codons that determine protein sequences
• The translating process will begin to form amino acids/codons from the base pairing

Question 11

Mutations

Answer 11

o Permanent change in an organism’s DNA, Modification in cell’s information archive, Change in genotype, New alleles
o There are different types of mutations

Question 12

Point Mutations

Answer 12

 Point mutations: result from one or a small number of base changes
* WE RUN INTO THESE
* Think of the mouse example, tiny change in genotype created a phenotypic change too!

Question 13

Point Mutation: Silent

Answer 13

change in nucleotide sequence that does not change the amino acid specificied by a codon

 Expected sequence
* THE CAT ATE THE RAT
 Silent
* THE CAT ATE ThE RAT
* Intent is the same, no change in meaning

Question 14

Point Mutation: Missense

Answer 14

change in nucleotide sequence that changes the amino acid specified by the codon

Question 15

Point Mutation: Missense

Answer 15

change in nucleotide sequence that does not change the amino acid specified by the codon

 Expected sequence
* THE CAT ATE THE RAT
 Missense
* THE CAT ATE THE BAT
* Changes what is being specified in being eaten

Question 16

Point Mutation: Nonsense

Answer 16

change in nucleotide sequence that results in an early stop codon

 Expected sequence
* THE CAT ATE THE RAT
 Nonsense
* THE CAT ATE
* It leaves a shortened sentence that is not detailed like it needs to be

Question 17

Frameshift

Answer 17

addition or deletion of a nucleotide

 Expected sequence
* THE CAT ATE THE RAT
* THE CAT ATT ETH ERA T
* Letters are not grouped in three anymore with deletion in the middle, moves the letters over