Answer:
At the microscopic level of a visceral muscle cell are actin and myosin filaments. They slide past each other in an antiparallel manner to shorten the distances between their ends. In a smooth muscle cell, the ends of chains of these functional units are attached to the cell membrane. They are several in a cell arranged in an elaborate framework. They contract together and deferentially to enable the muscle to contract as needed.
Correct answer: D
A pollen is where male gametes are produced and so the number of chromosomes, as we are talking about gametes, is n. This means that the grain of pollen will only have a copy of each gene, and therefore only one allele for each gene - one S, and one T or t. So, the possible combinations are ST and St.
I do not really know but i think that the answer is c but wait for other people