Answer:
A frameshift changes every codon past it. A base substitution only changes one codon.
Explanation:
DNA is comprised of nucleotides (A, C, T, G) that make up amino acids. Every three bases is called a codon and represents an amino acid.
In a frameshift mutation, a nucleotide is either added or deleted from the sequence. This offsets the entire sequence after it because the reading frame shifts. Here's an example:
ACTGCTATCGTCATC
If another T is added in between the first and second codons, then every codon after will be changed.
ACT>T<GCTATCGTCATC
A substitution mutation is usually less severe, as it only alters one codon in the sequence. These occur when one nucleotide is replaced by another one. Here's an example:
ACTGCTATCGTCATC
Let's say the first G is replaced by a T.
ACT>T<CTATCGTCATC
As you can see, none of the other codons changed.
Typically, a frameshift mutation is considered worse than a substitution mutation.
The question is incomplete, the complete question is:
A client with myasthenia gravis improves and is discharged from the hospital. The discharge medications include pyridostigmine bromide (Mestinon) 10 mg every six hours. The nurse evaluates that the drug regimen is understood when the client says, "I should:
1
Take the medication on an empty stomach."
2
Set an alarm so I take the medication on time."
3
Take my pulse rate before taking the medication."
4
Monitor for an increase in blood pressure after taking the medication."
Answer:
The correct answer is statement 2.
Explanation:
Pyridostigmine refers to an essential drug, which must be consumed on time, as a late or missed dose can lead to extreme neuromuscular and respiratory consequences or even death. Pyridostigmine should be consumed with a small concentration of food in order to inhibit gastric irritation.
It is not essential to take the pulse rate prior to taking the medication. Pyridostigmine may result in hypotension, however, not hypertension, which is not an indication of cholinergic crisis.
