Degeneracy
Degeneracy indicates that several codons can encode for the same amino acid during the process of protein synthesis from DNA. A codon comprises a triplet of <span>nucleotides that represents a specific amino acid.
This redundancy means that mutations (like point mutations) are less likely to disrupt the synthesis of proteins. For instance, if the codon sequence GAA, which represents glutamate, changes to GAG, glutamate will still be produced as the code is degenerate. </span>
The hearts of birds and mammals, which have four chambers, are accurately classified as homoplasies. In evolutionary terms, homoplasies refer to traits that are shared across different species, even though their common ancestors lacked these traits entirely. To illustrate, both bird and bat wings perform a similar function of enabling flight, yet these structures evolved separately without being present in their ancestors. Consequently, while birds and mammals each have a four-chambered heart, their predecessors only possessed three chambers. This independent evolution exemplifies homoplasy.
<span>The answer is b.0.5 to 1 micrometre thick.</span>
Typically, the thickness of the respiratory membrane measures around 0.6 micrometres. This membrane comprises alveolar epithelial cells, capillary endothelial cells, and basement membranes created by both alveolar and capillary cells.