The odd one out would be the crow
A model organism is a species that has been widely studied to understand a particular biological phenomena, normally used because they are easy to breed and maintain in a laboratory setting and has certain experimental advantage.
The criteria that Thomas hunt Morgan was looking for include; the model organism should be small in size, easy to keep in the laboratory and also able to produce large number of off springs in a short time.
So we know that to transport materials in or out of the cell, we need to have access to both the inside and outside of the cell. This would require that the protein be a transmembrane protein that reaches both the inside and the outside of the cell.
So in this case, let's look at pore proteins. These are proteins that cross a membrane and act as a pore for the materials that need to cross the membrane.
One example of a pore protein is an aquaporin. These proteins aid in the transport of water into or out of a cell.
Therefore, the answer to your question is: A) Pore proteins.
The cell cannot go through mitosis and will not produce a new cell
The motif is the repetitive supersecondary structures, an example of a motif is a beta-alpha-beta unit. The motifs are formed of the clusters of secondary structure.
On the other hand, the domains are globular and stable functional units in a protein. It may retain a three-dimensional configuration when distinguished from the rest of the protein.
Both the motifs and domains are stabilized by the hydrophobic interactions, they both are a unit of tertiary structure, and are dependent on primary composition.
