Organic material provides nitrogen for plants. which soil component contributes the most nitrogen to plants? clay humus sand silt

the correct answer on edg is Humus

Option (2)

Explanation:

Humus is defined as the dark colored, organic materials that are formed when the plants and animals after their decay are mixed with the soil. It provides all the essential nutrients that are required by the plants to grow and flourish. It includes nitrogen, carbon, potassium and phosphorous. It contributes a significant amount of nitrogen to the plants and this nitrogen is comprised of proteins and the chlorophyll pigments that helps the plants to carry out the process of photosynthesis.

Thus, humus provides nitrogen for plants.

Hence, the correct answer is option (2).

one centimetre is equal to 0.01 metres

cells use diffusion to get substances in and out of themselves. that diffusion will occur across the cell membrane or the outer covering of the cell. because we are talking about the surface of the cell, surface area and volume are  important factors here. as a cell increases in size, its surface area and volume increase as well.  we call that the surface area to volume ratio (sa: vol).  but the catch is that  volume increases at a greater rate than surface  area. in other words, as a cell gets bigger, the sa: vol gets smaller. so a really small cell like bacteria is mostly cell membrane (surface) with very little contents (volume). a really big cell like an egg, is mostly insides with a super thin membrane. so what ends up happening is that the cell cannot efficiently diffuse all of the stuff it needs in/out to survive. therefore cell size is limited to about 100mm. so how do we make organisms bigger than 100mm? cells divide! by dividing and becoming multicellular, organisms are able to grow!   check out the diagrams i attached to see the effect of sa: vol. i hope this ! good luck!