Answer:
A small structure within the cell that serves speciallzed functions.
Hope this helps
:D
The ductus arteriosus allows fetal blood to move from the pulmonary trunk into the aorta. The ductus venosus on the other hand is a fetal vessel that transports blood from the umbilical vein to the inferior venacava. Ductus arteriosus is a blood vessel connecting the main pulmonary artery to the proximal descending aorta. It allows most of the blood from the right ventricle to bypass the fetus's fluid-filled non-functioning lungs.
3. The product should use the least sig figs of the two numbers.
The inside surface area is shaped in a crescent. It consists of a spiral valve which is made up of the small intestine. Although the dogfish shark has a relatively short small intestine compared to other animals, therefore, the spiral valve allows for a more compact form of the small intestine.
Hence, this structure provides maximum surface area over a relatively short distance in order to make the absorption of nutrients efficient achieved from the food, the sharks had from eating different sea animals.