what is a gene?
a. the basic unit of a nucleic acid, made of a phosphate, sugar ring,
and nucleotide base
b. the segment of a dna chain that codes for all or part of a trait
c. a double-stranded molecule that codes instructions for an
organism's physical characteristics
d. a physical or behavioral characteristic of an individual

D.

Explanation:

In biology, a gene is a sequence of nucleotides in DNA or RNA that codes for a molecule that has a function. 

ecological efficiency: % of usable energy transferred as

biomass from one trophic level to the next typical is 10% efficient (90% of

energy is lost),is diagramed as the pyramid of energy flow. then osprey eagle

are tertiary consumer and the shrimp are primary consumer, so to balance

mass of shrimp (1/0.1) / 0.1 = 100 kg