17 - Translation

Question 1

Codon

Answer 1

the mRNA nucleotide triplets, customarily written in the 5’ to 3’ direction

Question 2

tRNA

Answer 2

(transfer tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis. Its primary function is to transport amino acids to the ribosome, where proteins are assembled

Question 3

Anticodon

Answer 3

the particular nucleotide triplet that base-pairs to a specific mRNA codon

Question 4

Aminoacyl-tRNA synthetases

Answer 4

a family of related enzymes

Question 5

Small and large ribosomal subunits

Answer 5

are a group of enzymes that play a critical role in the process of translation, which is the synthesis of proteins from messenger RNA (mRNA) templates

Question 6

Start codon

Answer 6

is a specific sequence of three nucleotides in messenger RNA (mRNA) that signals the beginning of protein synthesis

Question 7

Stop codon

Answer 7

is a sequence of three nucleotides in messenger RNA (mRNA) that signals the end of protein synthesis.

Question 8

Polysome

Answer 8

A string of ribosomes that can be seen with an electron microscope, they can be either free or bound

Question 9

Signal peptide

Answer 9

is a short sequence of amino acids at the beginning of a newly synthesized protein that directs the protein to its proper location within or outside the cell.

Question 10

SRP (signal recognition peptide)

Answer 10

a protein-RNA complex, escorts the ribosome to a receptor protein built into the ER membrane

Question 11

SRP receptor protein

Answer 11

SRP receptor is a protein located on the membrane of the endoplasmic reticulum (ER) that helps guide proteins to the ER during translation.

Question 12

Translocation complex

Answer 12

is a group of proteins in the membrane of the endoplasmic reticulum (ER) that helps move newly made proteins into or across the ER membrane during translation

Question 13

Silent substitution

Answer 13

refers to a type of genetic mutation at the DNA level where a change in a nucleotide sequence does not alter the amino acid sequence of the protein that is produced.

NO EFFECT ON THE AMINO ACID SEQUENCE

Question 14

Missense substitution

Answer 14

is a type of genetic mutation where a change in a single nucleotide in the DNA sequence results in the replacement of one amino acid with another in the protein.

A range of effects depending on the location within the
protein and the identity of the new amino acid

Question 15

Nonsense substitution

Answer 15

is a type of genetic mutation where a change in a single nucleotide in the DNA sequence creates a premature stop codon in the mRNA

Effect depends on how close the new stop codon is to the
beginning of the coding sequence

Question 16

Frameshift

Answer 16

is a type of genetic mutation that occurs when nucleotides are inserted into or deleted from the DNA sequence in numbers not divisible by three. This shifts the “reading frame” of the genetic code.

causing immediate nonsense (1-nucleotide-pair insertion)

causing extensive missense (1-nucleotide-pair deletion)

Question 17

codon addition or deletion

Answer 17

refers to the insertion or removal of a set of three nucleotides (a codon) in the mRNA sequence. Since each codon corresponds to one amino acid, adding or deleting a codon changes the number of amino acids in the resulting protein but does not shift the reading frame.

no frameshift, but one amino acid is missing. A 3 nucleotide pair insertion would lead to an extra amino acid