The following statements refer to a pyramid of energy.
I. Some material is not assimilated by each trophic level.
II. Energy transformations are never 100 % efficient.
III. Heat is lost during photosynthesis.
Which of the statements give the reason why a pyramid of energy is narrower at the top than at the bottom?
A. I only
B. I and II only
C. II and III only
D. I, II and III.

B. I and II only

Explanation:

Pyramid of energy is a model used to depict the flow of energy from one trophic level or feeding level to the next in an ecosystem. It's a diagram that compares the energy used by organisms at each trophic level of the food chain. The pyramid of energy must never be inverted or turned upside down.

The units used in the construction of pyramids of energy is kilocalories (kcal) or energy per area per time (Jm-²year-¹).

The following statements refer to a pyramid of energy;

I. Some material is not assimilated by each trophic level.

II. Energy transformations are never 100% efficient.

hydroxyl -oh

alcohols, always polar, can form hydrogen bonds with h2o molecules

carboxyl -cooh  

cargoxylic acids, has acidic properties which is a source of hydrogen ions, found in cells in ionized for with a charge of oh-1

carbonyl > co

ketone if within skeleton, aldehyde if group is at the end of skeleton, k & a may be structural isomers, it determines 2 sugars (ketose & aldose)

amino -nh2

amines, acts as a base, it can pick up h+ ions from surrounding solution, ionized with charge of 1+

methyl ch2

addition to rna/dna affects and gene expression

phosphate -opo3 ²⁻

organic phosphates, contributes to negative charge to, molecule that it is a part of, and potential to react with h20

sulfhydryl -sh

thiols, cross-linking stabilize the protein, and it is structure