HISTOLOGY
BLOOD VESSELS
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
to pump out hemolymph
|
|
|
to draw hemolymph back into the heart
|
|
|
Either A or B
|
|
|
None of the above
|
Detailed explanation-1: -As the heart beats and the animal moves, the hemolymph circulates around the organs within the body cavity, reentering the heart through openings called ostia (singular: ostium). This movement allows for gas and nutrient exchange.
Detailed explanation-2: -Hemolymph serves as a water storage pool for use by tissues during desiccation and as a storage depot for other types of chemicals. It also contains circulating cells called hemocytes.
Detailed explanation-3: -Coordinated movements of the body muscles gradually bring the hemolymph back to the dorsal sinus surrounding the hearts. Between contractions, tiny valves in the wall of the hearts open and allow hemolymph to enter. Hemolymph fills all of the interior (the hemocoel) of the animal’s body and surrounds all cells.
Detailed explanation-4: -Ostia are small, slit-like, paired openings in the dorsal vessel that allow hemolymph to enter or leave the vessel. Incurrent ostia allow hemolymph to enter during diastole and excurrent ones permit hemolymph to exit.