Chapter 39: The Genetic Code (Test 1) Flashcards
1
Q
What kind of RNAs function as catalysts?
A
- Ribozymes
2
Q
What do group 1 introns require as a co-factor?
A
- Guanosine
3
Q
What does protein biosynthesis require?
A
- Ribosomes
- mRNA
- tRNA
- Protein factors
4
Q
What activates amino acids?
A
- tRNA and aminoacyl-tRNA synthetases (an ester linkage)
5
Q
What encodes an amino acid?
A
- 3 nucleotides called a codon
6
Q
What does it mean to be degenerate?
A
- When amino acids are encoded by more than one codon
7
Q
What is the start codon?
A
- AUG
8
Q
What does AUG code for?
A
- Methionine
9
Q
What are the stop codons?
A
- UAA
- UAG
- UGA
10
Q
What does tRNA function as?
A
- An adapter molecule between a codon and an amino acid
11
Q
What is the 3D structure of tRNA?
A
- L-shaped
12
Q
What is the 2D structure of tRNA?
A
- A cloverleaf pattern
13
Q
What are the true translators of the genetic code?
A
- Synthetases because they assign a particular amino acid to a specific tRNA
14
Q
E. coli has what kinds of ribosome and subunits?
A
- A 70S ribosome
- A large 50S subunit
- A smaller 30S subunit
15
Q
What is ubiquitinylation?
A
- When ubiquitin bonds to proteins for destruction
16
Q
What are lysosomes?
A
- an organelle in the cytoplasm of eukaryotic cells that contain degradative enzymes
17
Q
What are proteasomes?
A
- Macromolecular structures that break down proteins tagged by ubiquitin.
