chpt 12

Question 1

where does DNA replication happen in eukaryotes?

Answer 1

the nucleus

Question 2

where does DNA replication happen in prokaryotes?

Answer 2

the cytoplasm

Question 3

semiconservative means what?

Answer 3

each double helix had an old and new strand, each serves as a template for a new strand

Question 4

what is the origin of replication?

Answer 4

starting point for replication

Question 5

helicase is when…

Answer 5

the double helix begins to unwind

Question 6

after helicase what is formed?

Answer 6

a replication fork

Question 7

what is DNA polymerase?

Answer 7

new strands of complementary DNA nucleotides is created for 2 template strands

Question 8

the new strand made in the direction for unwinding is called what?

Answer 8

the lagging strand

Question 9

fragments on the lagging strand are stitched together by what?

Answer 9

DNA ligase

Question 10

DNA polymerase has what type of ability?

Answer 10

proofreading ability

Question 11

what is the central dogma?

Answer 11

DNA —— RNA ——- Protein

Question 12

transcription begins where?

Answer 12

at the prometer

Question 13

does the double helix unwind in translation or transcription?

Answer 13

transcription

Question 14

mRNA processing only happens in what?

Answer 14

eukaryotes

Question 15

how many steps are in the mRNA processing?

Answer 15

3 steps

Question 16

what’s the 1st step in mRNA processing?

Answer 16

the addition of the 5’ cap

Question 17

what’s the 2nd step in mRNA processing?

Answer 17

the addition of DOLY (A) tail

Question 18

what’s the 3rd step in mRNA processing?

Answer 18

Splicing

Question 19

mature mRNA transcript leaves the nucleus through what?

Answer 19

nuclear pores

Question 20

3 mRNA nucleotides are equal to

Answer 20

1 codon

Question 21

the genetic code has how many codons in total?

Answer 21

64 or 4^3

Question 22

what is degeneracy?

Answer 22

redundancy

Question 23

most amino acids are encoded by?

Answer 23

more than 1 codon

Question 24

translation occurs where?

Answer 24

in the cytoplasm for both eukaryotes and prokaryotes

Question 25

ribosomes equal?

Answer 25

2 subunits (proteins+mrRNAs)

Question 26

prior to start translation, what happens?

Answer 26

amino acids are attached to 3' end of appropriate tRNA

Question 27

initiator tRNA binds to what?

Answer 27

mRNA at start codon

Question 28

fully assembled ribosomes have 3 docking sites. what are they called?

Answer 28

1. A (aminoacyl) site 2. P (peptidyl) site 3. E (exit) site

Question 29

A site does what?

Answer 29

holds next tRNA to be delivered to ribosomes by codon and anticodon interactions

Question 30

P site does what?

Answer 30

holds most recently delivered tRNA by codon and anticodon interactions

Question 31

what also starts in the P site?

Answer 31

tRNA met starts

Question 32

what does the E site do?

Answer 32

holds previously delivered tRNA and is now ready to leave the ribosome without the amnio acids

Question 33

what is elongation?

Answer 33

the amino acid chain gets longer

Question 34

what happens in translocation?

Answer 34

ribosomes shift from 5' to 3' and elongation repeats

Question 35

new proteins assembled one amino acid at a time or seen as....

Answer 35

N to C

Question 36

what occurs in translation termination?

Answer 36

when ribosome encounters a STOP codon a protein release factor binds to site A instead of a tRNA aa