Gas exchange involves the transport of two respiratory gases, oxygen and carbon dioxide. review how each gas is transported between the atmosphere and the cells of your body by completing this exercise. drag each statement into the appropriate bin depending on whether it applies to oxygen only, carbon dioxide only, or both oxygen and carbon dioxide.

Ablastocyst is a group of cells that forms after a human egg is fertilized. the blastocyst consists of two types of cells. some of these cells will become the placenta. what do the other cells develop into?

Why is excretion necessary to maintain homeostasis?

Research cheetahs on the internet what has contributed to this animal becoming "endangered" or "threatened." what animal you have chosen? -cheetah how long has the animal been endangered or threatened? what has contributed to this animal’s endangered or threatened status? why is it important to save this animal from extinction? after researching and gathering facts, write a 350-word letter from the point of view of an animal rights' activist. be sure to include at least five facts that you learned from your research.