explain the consequences for reproduction of vas deferens is surgically cut
Vasectomy Vasectomy is a surgical procedure for male sterilization or permanent contraception. During the procedure, the male vas deferens are cut and tied or sealed so as to prevent sperm from entering into the urethra and thereby prevent fertilization. Vasectomies are usually performed in a physician's office, medical clinic, or, when performed on an animal, in a veterinary clinicâ€”hospitalization is not normally required as the procedure is not complicated, the incisions small, and the necessary equipment routine.
Primitive streak The presence of the primitive streak will establish bilateral symmetry, determine the site of gastrulation and initiate germ layer formation. To form the streak, reptiles, birds and mammals arrange mesenchymal cells along the prospective midline, establishing the second embryonic axis, as well as the place where cells will ingress and migrate during the process of gastrulation and germ layer formation.[1] The primitive streak extends through this midline and creates the left–right and cranial–caudal body axes,[2] and marks the beginning of gastrulation.[3] This process involves the ingression of mesoderm progenitors and their migration to their ultimate position,[2][4] where they will differentiate into the mesoderm germ layer[1] that, together with endoderm and ectoderm germ layers, will give rise to all the tissues of the adult organism.