Answer:
plant cells only
Explanation:
animal cells have no cell wall.
Answer:
four billion years ago the earth had a layer of ozone gas
Answer: helps cool the body
removes waste chemicals through pores in the skin
Explanation:
Perspiration is a natural biological process that occurs in an mammals including human beings. Perspiration is required to maintain the homeostasis of the body. Homeostasis is the condition of maintenance of stable internal environment of the body with respect to the changes occurring in the external environment. Perspiration is also called as sweating when the body is exposed to heat it secrete sweat in order to provide coolness to the body. As the sweat contents are evaporated in the exposure of air. The sweat contents are emerge out by the pores present on the skin surface. The sweat consists of chemicals like aminoacids, salts and excess of water. Therefore, sweat removes the waste chemicals through the pores of the skin.
Answer:
Top soil is eroded by rain water.