No, not every scientific method begin with an observation. on basis of what we want, steps for scientific method changes.
And in scientific method before observation, first we predict (what will happen in the experiment). after prediction we observe. Prediction is known as hypothesis. And observation is what we are viewing.
Answer:
oxygen
Explanation:
6CO2 + 6H2O + light ----> C6H12O6 + 6O2
Oxygen (O2) is an element, so it cannot be broken on smaller units.
Plant absorb sulfur and phosphorus through the insecticide sprayed on the leaves.
Occipital lobe.
Hope this helps! :)
Answer:
D. the need for a surface area of sufficient area to allow the cell's function
Explanation:
Many cellular functions such as the exchange of substances and respiratory gases, absorption of nutrients, cell-cell communication, etc. require the cells to have a sufficient surface area. A small cell has a larger surface area to volume ratio and therefore, maintains a higher rate of exchange of substances. As the cell increases in size, the surface area grows less than its volume. Therefore, the surface area required to perform the cellular functions puts an upper limit on the cell size.
Cells maintain the required surface area by dividing and/or by developing folding or projections on the surface. For instance, the cells in the wall of the small intestine require to maintain a higher surface area for nutrient absorption. Therefore, the cells of the wall of the small intestine develop microvilli to have a larger surface area which in turn supports a relatively higher rate of absorption.
