<span>in green plant cells a plastid that contains chlorophyll, and then which photosynthesis takes place.</span>
Answer and Explanation:
The gene pool is the sum of all the alleles in a population. Sometimes, allele frequencies within a population change randomly with no advantage to the population over existing allele frequencies. This phenomenon is called genetic drift.
Answer: B soil is also called the SUBSOIL.
Soil horizon consists of layers of soil that differ physically. It contains 3 or 4 layers or horizon such as O horizon, A horizon, B horizon, C horizon and R horizon. B horizon is also referred as subsoil. It is yellowish to brown in color. It consists of mineral layers such as silicate clay, iron, aluminium, gypsum, silica, humus, etc. The roots of a plant penetrates through the subsoil.
