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.
Answer:
Explanation:
Using its web as a gill, the diving-bell spider can live underwater with only occasional visits to the surface. The arachnid (Argyroneta aquatica) breathes air from a bubble that it grabs from the surface of water using fine hairs on its abdomen.
Answer:
(C)cell nuclei that contain DNA
Explanation:
They are eukaryotic, which means they have a nucleus. Most have mitochondria. They can be parasites. They all prefer aquatic or moist environments.
There are 6 elements that are the most important. The acronym, CHNOPS, is an easy way to remember these.
C - Carbon
H - Hydrogen
N - Nitrogen
O - Oxygen
P - Phosphorous
S - Sulfur
