The correct answer is:
fixation
Explanation:
Nitrogen fixation is a method by which nitrogen in the Earth's atmosphere is converted into ammonia or other molecules prepared to living organisms. Nitrogen fixation is carried by a diversity of bacteria, both as free-living organisms and in symbiotic association with plants. Because it is the primary source of the nitrogen in the soil, nitrogen that plants need to grow, nitrogen fixation is one of the most critical biochemical processes on Earth
D. Course-grainedI believe................................
Well the soil classification is usually done on the basis of particle sizes and composition of soil.
<span>Clay </span>usually consists of particles less than 0.075 mm in size. It is a sticky soil and shows great changes in volume with variation in its water contact. It also shows considerable strength when air dried.
<span>Silt </span>has larger particles than clay and are mainly inorganic in nature. The particle size is less than 0.075mm and exhibits slightly plastic or non plastic behaviour.
Humus is soil consisting of dead and decaying organic matter. It is mainly organic in content but some inorganic particles may be mixed in it. The top soil in a tropical forest may be considered as humus.
The image shows a phospholipid bilayer. Macromolecules that make up most of the structure that is shown are proteins and lipids. Lipids can make up 20% to 80% of the membrane depending on the location and type of the cell. The rest is made up of proteins.
