The chamber is the left atrium.
The lungs help exchange the deoxygenated blood which are full of wast materials into oxygenated and blood full of nutrients. These oxygenated blood are then transported through the pulmonary vein, the only vein in the body which transports oxygenated blood. These blood are then transported back into the heart, which is the left atrium specifically.
Those blood is then pushed down to the left ventricle, and then pumped to the whole body (except lungs), in order to keep the body functioning by providing oxygen and nutrients for cellular respiration.
Meanwhile, the deoxygenated blood are received by the right atrium, and is then transported back to the lungs for exchange again, through the right ventricle and pulmonary artery.
D. Polar regions receive less solar energy and heat per unit area than tropical regions
Less direct sunlight means that there is less concentration of direct solar rays. This would influence temperature and would ultimately create weather, and since this pattern continues of switching direct ray latitudes, this would create climate zones all over the Earth, and similar ones with similar latitude and terrain.
Maybe, not sure, may need to check yahoo answers for this one
Answer:
The correct answer is -Sponges lack true tissue but have morevariation in cell type than animas in oter phylum.
Explanation:
Sponges are belong under phylum porifera which have diverse form encrusting sheets to volcano shaped mounds.
The tubes that contain in their body are differ in size from millimeter upto one meter.
The poriferans contain canal system and with help of this, they pump water which enters through a specialed pores called ostia that flows through canal called spongocoel and finally the water exits from their body through oscula.
The sponges show complex organization as their body contain single tube with 2 cell layer thick.
Ascon,leucon,sycons are the level of complexity.