Genetic Code

Question 1

The genetic code connects the sequence of ___ ___ in a gene and its mRNA to the sequence of amino acids in a ____

Answer 1

nucleotide bases, protein

Question 2

___ bases code for one amino acid

Answer 2

three

Question 3

Code words that are three bases in length can specify __ amino acids

Answer 3

64

Question 4

How many possible bases are there at each position?

Answer 4

4 possible bases (A,C,G or U)

Question 5

The code words are ____

Answer 5

non-overlapping

Question 6

The sequence is read continuously from a ___ starting point

Answer 6

fixed

Question 7

The first base of the first code word must be identified. It can be located ____. AKA it might not be at the start

Answer 7

anywhere

Question 8

Each amino acid can be coded by more than one __ __

Answer 8

code word

Question 9

mRNA sequences have ___ possible reading frames

Answer 9

3

Question 10

The precise identification of the translation start site is essential to have the reading frame with the correct ___ ___ sequence

Answer 10

amino acid

Question 11

what are the 3 stop codons before the 3’ end?

Answer 11

UAA, UAG, UGA

Question 12

what is the start codon from the 5’ end?

Answer 12

AUG

Question 13

You can get up to __ code words per amino acid

Answer 13

6

Question 14

what two amino acids are not coded by more than one sequence?

Answer 14

MET & TRP

Question 15

How many code words does SER have?

Answer 15

6

Question 16

___ out of the 64 amino acids specify amino acids

Answer 16

61

Question 17

what two amino acids are not coded by more than one sequence?

Answer 17

MET, TRP

Question 18

what codon is used the most in e coli?

Answer 18

CUG

Question 19

what codon is used the least in e coli?

Answer 19

CUA

Question 20

what codon is used the most in humans?

Answer 20

CUG

Question 21

what codon is used the least in humans?

Answer 21

UUA

Question 22

Code words for the same amino acid are not used equally, and large variations in the use of code words are found for ___ ___ and __ ____ ___

Answer 22

Human genes, E. Coli Genes

Question 23

Each codon specifies only __ amino acid

Answer 23

one

Question 24

Every amino acid is coded by more than one codon, expect for ___ and ___

Answer 24

Met and Trp

Question 25

Codons for the same amino acid/chemically similar amino acids tend to have similar ____

Answer 25

sequences

Ex: all four codons with the sequence GGX, where X is U,C,A or G, code for glycine

Question 26

The genetic code is almost universal: all living systems use the same __ ___

Answer 26

genetic code

Question 27

Mitochondrial genomes show some differences; for example, UGA specifies ___ rather than stop

Answer 27

TRP