The predominant hypothesis for why the animals needed some 3 billion years to evolve after the life first appeared on the planet is that the conditions were not right for them to appear.
The life on Earth has appeared much earlier that what we normally assume, and also it has not been evolving very quickly, but instead it has been a very slow and gradual process. The reason for that is that the living conditions on the Earth were much different than what are they now, or anytime from the Cambrian period until the present.
The surface was still pretty hot, and there was intense volcanic activity. The composition of the atmosphere was not suitable for animals to appear at all, and in fact it would have been toxic for them. The water too had chemicals in it that were not providing the right conditions for animals to evolve. It was only after the plants started to appear and managed to make lot of changes in the water, atmosphere, and land, than the animals were able to evolve and develop.
One of the biggest sources is called nonpoint sources pollution which occurs as a runoff. Hope this helps out
i feel that way sometimes too
You could say variation in offspring (so cloning things they basically just multiple the exact same thing but with reproduction, whatever is made differs a little bit or a lot from its "parents"
Answer:
Cilia
Explanation:
The respiratory system is the system of organs which allows the inhalation and exhalation of the gases especially oxygen and carbon dioxide. The respiratory system begins from the nose or nasal passage and end at the lungs.
The histology of the respiratory passages reveals that the epithelium layer of these is made of the columnar, cuboidal and the simple squamous epithelium along with ciliated structures. These ciliated structures allow the movement of the mucus secretions and the other cell by whiplash movement.
In the given question, since the epithelium of the person is not able to move the fluid therefore the structure that is involved in the cilia.
Thus, cilia is the correct answer.
