Identify, in which of the following carbon compounds, heterocyclic rings can be found?
Proteins
Amino acids
Nitrogen bases
Lipids
Related Questions
Which of the following is NOT a component of a nucleotide?
Nitrogenous base
Pentose sugar
Phosphate group
Amino acid
If a DNA strand has the sequence 5'-ATGC-3', what is the sequence of its complementary strand?
5'-TACG-3'
3'-ATGC-5'
5'-GCAT-3'
3'-TACG-5'
Which structural modification to a eukaryotic mRNA is MOST crucial for preventing its degradation by exonucleases in the cytoplasm?
Splicing out of introns
Methylation of specific adenine residues
Association with ribosomes
Addition of a 5' cap and a 3' poly(A) tail
A mutation in a tRNA molecule alters its anticodon sequence from 3'-AUC-5' to 3'-AUA-5'. Assuming the wobble hypothesis applies, which of the following changes in protein synthesis is MOST likely to occur?
Protein synthesis will be terminated prematurely.
A different amino acid will be incorporated at the corresponding codon.
The mutant tRNA might recognize a different codon but still incorporate the same amino acid.
The mutation will have no effect on protein synthesis.
One turn of DNA has nucleotide pairs
8
100
6
10
Which nitrogenous base is found in RNA but not in DNA?
Adenine
Guanine
Thymine
Uracil
The double-helix structure of DNA is stabilized by:
Covalent bonds
Ionic bonds
Hydrogen bonds
Van der Waals forces
The bond linking the sugar and base in a nucleoside is:
Phosphodiester bond
Hydrogen bond
Peptide bond
N-glycosidic bond
A novel virus is discovered with a single-stranded nucleic acid genome. Treatment with RNase H significantly reduces its infectivity, while DNase I has no effect. Further analysis reveals the presence of short RNA fragments complementary to the genome. What can be most confidently inferred about the viral genome?
It is a single-stranded RNA virus that replicates through a DNA intermediate.
It is a single-stranded DNA virus that replicates through an RNA intermediate.
It is a single-stranded RNA virus that replicates through a double-stranded RNA intermediate.
It is a double-stranded RNA virus.
