Tropical climate is a region of the earth surrounding the equator. When the earth is exposed to light from the sun it is right over the equator and up 23 degrees of latitude Tropic of Cancer in the northern hemisphere and Tropic of Capricorn in the southern hemisphere
4 chambers in the heart and mammals and birds have the same number of chambers
This answer is about animals cell. first the deoxygenated blood goes to heart right side. then the heart pump the deoxygenated to lungs where the concentration of oxygen is higher so lungs make the D ox blood oxygenated and then sent again to heart left side which heart pump to deliever to all parts of body.
short cut= lungs and heart make the blood oxygenated.
hope it well help you
