Respiratory system helps in breathing and it leads to exhalation of the gas carbon dioxide which is not required by the body. The integumentary system is the first line of defense and protects the body from invadig microbes, dust, and other harmful substances. The digestive system protects the body by enabling digestio of food and providing energy to sustain, further the toxic waste materials are also released during the process.
Cyanobacteria or simply known as blue-green algae may have formed the oxygen into the early atmosphere. This is because these micro-organism has the capability to photosynthesize wherein they can produce oxygen and carbohydrates. In fact, all the plants contribute in the fomation of oxygen.
Answer:
Fossils are the preserved remains or traces of animals, plants, and other organisms from the past. Fossils are important evidence for evolution because they show that life on earth was once different from life found on earth today
Explanation:
Answer: Vacuole
Answer choices:
<span>Cell membrane
Mitochondrion
Nucleus
Vacuole</span>
Vacuoles<span> are membrane-bound structures found in both animal and plant cells. </span>
They have three important functions in plants -- provide support or rigidity, a storage for nutrients and waste matter until it can be removed, and decompose complex molecules.
