New: The Genetic Code

Question 1

how many genes are in the human genome

Answer 1

~25,000

Question 2

what is the myth about junk DNA

Answer 2

> 98% does not encode a gene when really >80% of DNA is active and needed

Question 3

peptide bond form between

Answer 3

two amino acids

Question 4

peptide bonds occur inside

Answer 4

ribosome

Question 5

ribosomes attatch themselves to

Answer 5

the mRNA molecule

Question 6

a tRNA molecule arrives and brings an ___ ___ to the first of 3 bases (codon) on the mRNA

Answer 6

amino acid

Question 7

amnio acids keep linking and lengthening the polypeptide chain until

Answer 7

a termination (stop) codon is reached

Question 8

codons

Answer 8

three letter genetic code

Question 9

is code overlapping

Answer 9

no

Question 10

translation

Answer 10

4 letter nucleic acid alphabet is translated into 20 letter protein alphabet

Question 11

tRNA

Answer 11

adapters between mRNA and proteins

Question 12

reading frame

Answer 12

each potential starting point for interpreting the 3 letter code frame

Question 13

nonoverlapping code is important because a single nucleotide mutation will only change

Answer 13

one codon

Question 14

how many reading frames are there of mRNA

Answer 14

3

Question 15

deletions and insertions are what type of mutations

Answer 15

frameshift

Question 16

silent, nonsense (stop) and missense are what type of mutations

Answer 16

point

Question 17

any given code only specifies for ____ amino acid

Answer 17

one

Question 18

there are ___ ____ for most amino acids

Answer 18

multiple codons

Question 19

termination codons

Answer 19

UAA; UGA; UAG

Question 20

initiation codon

Answer 20

methionine codon AUG

Question 21

the code has directionality and is read

Answer 21

5’ –> 3’

Question 22

transfer RNA molecules are the _____ of the genetic code

Answer 22

interpreters

Question 23

every cell contains at least ___ tRNA

Answer 23

20 - one for every amino acid

Question 24

each tRNA recognizes at least ___ codon

Answer 24

one

Question 25

what shape to tRNAs have?

Answer 25

L

Question 26

secondary structure of tRNA is

Answer 26

cloverleaf

Question 27

tRNA has a ____ ____ and four arms

Answer 27

acceptor stem

Question 28

acceptor stem

Answer 28

amino acid becomes covalently attached to tRNA at the 3’ end of this stem

Question 29

anticodon arm

Answer 29

contains the anticodon

Question 30

anticodon

Answer 30

a three-base sequence that binds to a complementary codon in mRNA

Question 31

tRNA anticodons base pair with

Answer 31

mRNA codons

Question 32

tRNA molecules are named for the

Answer 32

amino acids they carry

Question 33

base pairing between codon and anticodon is governed by rules of

Answer 33

watson-crick A-U G-C

Question 34

____ allows some tRNA molecules to recognize more than 1 codon

Answer 34

wobble

5’ anticodon position has some flexibility in pairing

Question 35

isoacceptor tRNA molecules

Answer 35

different tRNA molecules that bind the same amino acids

Question 36

synthesis of long proteins requires a low

Answer 36

error frequency

Question 37

amino acids are activated by attachment to

Answer 37

transfer RNA

Question 38

aminoacyl-tRNA

Answer 38

amino acids are covalently attachedto the 3’ end of each tRNA

Question 39

aminacyl-tRNA synthetases

Answer 39

catalze reactions

Question 40

amino acids are adenylated =

Answer 40

aminoacyl adenylate

Question 41

transfer aminoacyl group of aminoacyl-AMP to a specific tRNA molecule to form

Answer 41

aminoacyl-tRNA

Question 42

critical step of aminoacyl-tRNA synthetase

Answer 42

attachment of the correct amino acid to the corresponding tRNA

Question 43

______ binds ATP and the correct amino acid

Answer 43

synthetase

Question 44

synthetase may recognize the ____ as well as the _____ ___

Answer 44

anticodon; acceptor stem

Question 45

the equivalent of ___ ATP molecules consumed in synthesis of each ____ ___

Answer 45

aminoacyl tRNA

Question 46

aminoacyl-tRNAs are _____ ____ molecules

Answer 46

high-energy

Question 47

the aminoacyl-AMP never leaves the active site of the

Answer 47

synthetase

Question 48

a ribosome is a ribonucleoprotein particle made of

Answer 48

two subunits

Question 49

the ____ is the site of protein synthesis

Answer 49

ribosome

Question 50

ribosomal RNAs play a central role in

Answer 50

protein synthesis

Question 51

ribosomal RNA is the actual catalyst for

Answer 51

protein synthesis