Answer: d. C (parent rock)
Soil horizons are the layers lying parallel to the surface or subsurface layers of soil. These horizons are formed in the process of soil horizon. These sequence of soil horizons is collectively called as soil profile.
The layer or soil horizon, which is least likely to be penetrated by plant roots is C horizon. The C horizon is a layer of soil, which consists of huge aggregates of parent rocks, which are unweathered or partially weathered, lying deep in the bottom of the soil profile. It does not contain organic matter. Also, the texture of the soil is not fine, instead hard rocks are present. Therefore, this layer of soil cannot be penetrated by plant roots.
All living things need to have cells before they are said to be living. this is because the cell is the basic unit of life.
I believe the answer for the above question is Gene pools. Gene pools are the total number of genes of every individual in an interbreeding population; contains variations in genes, the relative gene frequencies, and also the allele frequencies. Relative frequency being the average number of occurrences of a particular event in a large number of repeated units while the allele frequency of an allele compared to other alleles of the same gene in population.
I would say that this is true, I don’t know much about it but I’ve read that they do release toxins
Osteoporosis, which literally means porous bone, is a disease in which the density and quality of bone are reduced. As bones become more porous and fragile, the risk of fracture is greatly increased. The loss of bone occurs silently and progressively.
