Answer:
Firstly, the partial pressure of nitrogen (78%) is crucial to breathing purposes. Without this pressure, the lungs will burst and animals cannot survive.
Secondly, nitrogen is required for the formation of amino acids (building blocks of proteins) and other organic compounds that are necessary for the survival of living organisms. Principally, in the atmosphere, nitrogen is present in the form of molecular nitrogen (N2). N2 is fixed by nitrogen-fixing bacteria that form nitrates and nitrites. These molecules are then used in biochemical processes to produce proteins (amino acids) and other organic compounds. In the absence of nitrogen, these processes could become seize of limited significantly thus affecting life overall.
Thirdly, nitrogen and its derivatives act as greenhouse gases that maintain the Earth's temperature within a range that supports life. Yes, the increased abundance of nitrous oxides is not good because of acid rain and other issues, however, still, the presence of nitrogen is important for life on this planet.
Answer:
Gravity is the main force responsible for mass movements. Gravity is a force that acts everywhere on the Earth's surface, pulling everything in a direction toward the center of the Earth. On a flat surface, parallel to the Earth's surface, the force of gravity acts downward
Explanation:
Answer:
The correct answer will be option a and b.
Explanation:
The food is digested and absorbed in the small intestine, a long folded tube which lengths about 20 ft or 6m.
The small intestine increases the surface area for food absorption as they have circular folding as well as the finger-like projections called villi and microvilli in the lumen of the intestine. These villi help in absorption of the nutrients from the intestine.
Thus, option a and b are the correct options.
Answer: Option C) Root hairs have an elongated shape that increases the surface area-to-volume ratio.
Explanation:
The larger surface area-to-volume ratio of root hairs enables them to rapidly absorped water molecules and nutrients along their elongated shape while aiding their upward transport from the root up the shoot (through the xylem vessels).
