Ch 8 Microbial Genetics

Question 1

define the genome

Answer 1

all genetic info within an organism

Question 2

how many chromosomes (bacteria v people)

Answer 2

bacteria-1 circular, also contain short circular chromosomes w unique capabilies (plasmids)
people- 23 pairs, linear

Question 3

define a gene

Answer 3

segments of DNA that code for functional proteins

Question 4

all genes in a bacterial chromosome are scattered except for

Answer 4

genes associated w membrane synthesis

Question 5

bacterial chromsomes, unlike eukaryotes, lack

Answer 5

introns

Question 6

what are introns

Answer 6

“interviening sequences” dont code for proteins

Question 7

what are exons

Answer 7

portions of DNA that code for proteins, are expressed

Question 8

what are histones? do eukaryotes or prokaryotes have?

Answer 8

eukaryotes have; special proteins w DNA wrapped around them, for DNA regulation

Question 9

what is replication

Answer 9

parent cell replicates DNA, divides via binary fission –> 2 daughter cells

Question 10

where bacterial chromosome is located in bacteria

Answer 10

attached at one or more points on PM

Question 11

what are short tandem repeats (STRs) in the bacterial chromosome

Answer 11

non-coding regions made up of repeating sequences of 2-5 bases

Question 12

enzyme that unwinds two strands of parental DNA for replications

Answer 12

helicase

Question 13

enzyme that fixes improperly paired bases by removing and replacing bases

Answer 13

replication enzymes

Question 14

newly added nucleotides are joined to the DNA (synthesizes DNA)strand by; also proofreads what it puts down

Answer 14

DNA polymerase

Question 15

point at which replication occurs

Answer 15

replication fork

Question 16

enzyme that makes covalent bonds to join DNA strands, also joins Okazaki fragments

Answer 16

DNA ligase

Question 17

the leading strand is in what direction vs the lagging

Answer 17

leading 5’-3’

lagging 3’-5’

Question 18

this enzyme is needed for replication of the lagging strand which synthesizes short RNA primers

Answer 18

Primase

Question 19

what DNA polymerase does to RNA primer once recognizing on lagging strand

Answer 19

digests; replaces w DNA

Question 20

what supplies the energy for

Answer 20

the nucleotides(nucleoside triphosphates)

Question 21

DNA expression within a cell involve what two processes

Answer 21

transcription & translation

Question 22

what is transcription

Answer 22

synthesis of complementary strand of RNA from a DNA template

Question 23

U replaces __ in RNA

Answer 23

T (A-U)

Question 24

What is translation

Answer 24

mRNA serves as information source for synthesis of proteins

Question 25

The language of mRNA is in the form off groups of 3 nucleotides called

Answer 25

Codons

Question 26

Each codon codes for

Answer 26

An amino acid

Question 27

Start codon

Answer 27

AUG (methionine)

Question 28

What indicated where a gene begins ( where RNA polymerase binds to begin transcription) What I indicates end?

Answer 28

Promoter | End= terminator

Question 29

What must happen in eukaryote mRNA (after transcription) before it can be translated and proteins can be made

Answer 29

Introns must be removed; splicing in nucleus until mRNAhave no introns

Question 30

Why transcription and translation occur simultaneously in prokaryotes

Answer 30

Bc no nuclear envelope and no introns

Question 31

How ribosomes know where to begin on mRNA when synthesizing proteins (transcription)

Answer 31

At start codon (AUG)

Question 32

The first amino acid that tRNA pairs during translation

Answer 32

Methionine

Question 33

The place where 1st tRNA sits in ribosome

Answer 33

P site

Question 34

The second tRNA to enter a ribosome sits in which site

Answer 34

A site

Question 35

Site of ribosome which releases tRNA

Answer 35

E site

Question 36

Kind of bond that forms between amino acids when attaching during translation

Answer 36

Peptide

Question 37

How tRNA recognizes the codon it is complimentary to

Answer 37

It’s anticodon (sequence of 3 bases complimentary to the codon)

Question 38

What tRNA anticodon is complimentary to the start codon

Answer 38

UAC

Question 39

A stop codon is also called a ___ codon

Answer 39

Nonsense codon

Question 40

Particles that remove introns from eukaryotic mRNA and splice exons together

Answer 40

small nuclear ribonucleoproteins (snRNPs) “snurps “