Answer:
D. 3:1
Explanation:
Gregor Mendel, in one of his numerous studies, performed a cross between purebred dominant (TT) pea plants and purebred recessive (tt) pea plants. All the offsprings of this cross appeared heterozygous tall (Tt) in the F1 generation.
However, when he self-crossed the F1 generation i.e. Tt × Tt, Mendel obtained a phenotypic ratio of 3 tall plants (dominant traits) : 1 short plant (recessive). This showed that the masked gene (recessive) was still present.
The answer is ganglia. As indicated, they house many cell
bodies of afferent and efferent neurons.
Spinal ganglia are located in the dorsal (that contain cell bodies of afferent
neurons) and ventral roots (that house cell body
of efferent neurons) of a spinal nerve.
The circulatory aids with the immune system because they provide white-blood cells to help fight with the diseases or sicknesses.