The circulatory and respiratory systems work together to circulate blood and oxygen throughout the body. Air moves in and out of the lungs through the trachea, bronchi, and bronchioles. Blood moves in and out of the lungs through the pulmonary arteries and veins that connect to the heart.
The answer Is B A new Species is forming
An allele. It’s a variant of a cell.
Answer:
Frogs have smooth or slimy skin that is moist, whereas toads have thicker, bumpy skin that is usually dry. All toads are poisonous, while frogs are not.
<span>a substance required in relatively larger amounts by living organisms</span>
