Answer:
The three layers of smooth muscle consist of the outer longitudinal, the middle circular, and the inner oblique muscles. Construction of these muscles helps mix and break the contents into a suspension of nutrients called chyme and propels it into the duodenum.
I believe the answer is a. crossing over
Varieties of plants in which self-fertilization produces offspring that are identical to the parents are referred to as true-breeding. In this process the parents will pass down specific phenotypic trait of their offspring. True bred organisms will have pure genotype (genetic make up of an organism) and will therefore produce certain phenotype.
I would say ones that can be seen, it affects the physical era of life eg H20 one of its physical qualities is its clear... coloress
