Answer:
True
Explanation:
There are certain limitations associated with the Punnett Squares. They are not useful in case of complex genetic inheritance such as linkage between two genes. In case of linkages it becomes difficult to estimate the distribution of genotypes and phenotypes. For example in case of Nail-patella Syndrome and gene associated with blood group two genes lie on the same chromosome in close vicinity and hence there are high chances of inheritance of these traits in the offspring from the parent thereby causing random distribution of the two traits. This random distribution cannot be captured through punnet square.
The same problem is associated in case where a single gene is determined by multiple genes with graded effects of each gene.
The answer is; producing a unique antibody from all other B cells by genomic rearrangement.
An isolated B cell produces monoclonal antibodies (also called Immunoglobulins). Different B cell types produce different types of antibodies (hence the serum of an animal has polyclonal antibodies). Memory B cells are developed when a particular infection is eradicated by the immune system. These B cells proliferate when the infection returns by producing the same antibodies that were effective against the foreign entity.
A. Sharks store enough urea to match the total solute concentration of the surrounding seawater