A ventricle's walls are thicker than those of the atrium because it needs to generate higher pressure. This higher pressure is needed to push blood into the circulation, while the atrium only needs to push blood into the ventricle.
The single ventricle of the frog has thicker walls. Because the atrial chambers have to push the blood to nearby ventricle only. So atrial chambers do not need much power and so the walls are thin. The ventricle has to pump blood to the lungs and body. So the wall of ventricle is much thicker.
I believe you meant to type "lower" instead of "lover". The lower chamber is the ventricle. Reptiles (and birds) have a three-chambered heart (two atria and one ventricle). Mammals have a four-chambered heart (two atria and two ventricles).
Any class of vertebrate with a three-chambered heart has two atria and one ventricle. An example would be amphibians such as frogs.
A frog has two atria (above) and one ventricle (below) unlike us, we have 2 atria and 2 ventricles.Read more: What_is_the_lower_single_chamber_of_the_frog's_hearts
Frogs have hearts that are 3 chambers. The ventricle has a thick wall and the two atria have thin walls.
Frogs have a 3-chamber heart (a ventricle and 2 atria), lungs, pancreas, fat bodies, spleen, testes, ovaries, ovaducts. The males even have a vestigial ovaduct.
because the ventricle is carrying the blood toward the heartBecause the ventricle has to pump blood all over the body whereas the atrium only pumps it to the ventricle.
NO they do not. They have four chambered hearts.
A frog heart has only 1 ventricle, but 2 atria. Oxygen poor and oxygen rich blood mix and are pumped out to the body at the same time as to the lungs.
Frogs have two atria just as humans do.
Ventricle
First, the frog heart (amphibian) has a three chambered heart, two atria and one ventricle. The ventricle is not fully separated; it's partly separated by the conus arteriosus. The blood, however, stays mostly unmixed. The ventricles delivers oxygenated (efferent) blood to the systemic and pulmocutaneous arteries. The human heart has four chambers, and its two ventricle are fully separated. The fresh efferent blood from the lungs goes to the systemic aorta.
Frogs have 9 organ systems: the integumentary, circulatory, skeletal, digestive, muscular, nervous, respiratory, excretory and the reproductive systems.