They play huge role in organisms, every living organism needs proteins.
- enzymatic role ( they build enzymes which lower an activation energy in reactions and increase reaction speed)
- hormonal role (they build hormons)
- structural role (for example keratin)
- transport role ( for example hemoglobin)
- energetic role ( for example aleurone grains in plant cells or they are used to gain energy in human organism when it's out of lipids and carbohydrates)
The correct answer is - a front.
On this image, the lines are representing a front, and since the signs are marked with blue color, it means that it is a cold front. The fronts are advancing masses of air. In this case, we have a cold front, thus we have advancing cold air masses in the western part of the US, and in the Great Lakes region and the northeastern part of the country. This means that these areas will be affected by colder air masses, that will bring in higher air pressure, colder weather, and cold winds from the direction from which these cold fronts are coming.
Many farmers in less densely populated area, such as Amazonia, practice slash and burn agriculture, also known as shifting cultivation or swidden agriculture where an area is cleared and then burned for the vegetative remains to release nutrients back into the soil. Shifting cultivation is a system where a farmer uses a piece of land, only to abandon or alter the initial use a short time later. Advantages of shifting cultivation includes; enhance control of pest and disease, inorganic matter addition which provide nutrient to crop, an effective way of weed control
