During exercise there is an increase in physical activity and muscle cells respire more than they do when the body is at rest. The heart rate increases during exercise. The rate and depth of breathing increases - this makes sure that more oxygen is absorbed into the blood, and more carbon dioxide is removed from it.
Cytoplasm maintains the internal pressure in the cell.
The ability of an organism to make a copy of itself is called Reproduction
Vestigial structures are often homologous to structures that are functioning normally in other species. Therefore, vestigial structures can be considered the evidence for evolution, the process by which beneficial heritable traits arise in populations over an extended period of time.
Answer:
As the spies of a cactus are modified leaves, they have ar spaces.
Explanation:
However, leaves of cactus are not like every other leaf. These leaves are in the form of spines to save the amount of water that the cactus needs.
Most of the amount of water, cactus s saving in its root. Also, the stem of a cactus is used for making food, and this is also the way of saving the water.
