Only about 3 percent of the worlds water is fresh, and even less than that is usable, because most of it is locked up in glaciers or in permanent snow fields.
The correct answer is D.
it would be B. the intertidal zone only cover by high tides
The four important characteristics of respiratory surface are:
1. Thin walls
2. Moisture
3. Large surface area
4. Blood supply
Respiratory system or respiratory tract is divided into upper and lower tract. Upper respiratory tract includes nose and its cavities, sinuses, pharynx and the part of the larynx. Lower respiratory tract consists of the trachea, bronchi, bronchioles and the alveoli.
Alveoli are the ends of the respiratory tract the smallest units in it. Alveoli are small folded air sacs that are branching off from alveolar ducts and providing an extremely large surface area for the gas exchange. Gas exchange occurs thanks to small blood vessels – capillaries that surround alveoli and it occurs via the process of diffusion.
So, respiratory surface is thin membrane also known as the blood–air barrier that consists of the alveolar epithelial cells, their basement membranes and the endothelial cells of the alveolar capillaries.
Explanation:
I would change its existing soil. some trees and shrubs thrive if you replace existing soil with certain minerals and fertilizers where you plant the Bush..
in my case, we have clay soil poor 4 most plants., b4 planting outside, put fertilized soil in the hole your planting 1st, then existing soil..
Answer:
The nitrogen cycle is a repeating cycle of processes during which nitrogen moves through both living and non-living things: the atmosphere, soil, water, plants, animals and bacteria. In order to move through the different parts of the cycle, nitrogen must change forms.
