Down syndrome can occur a. as a result of translocation during mitosis. b. most frequently in the offspring of women under the age of 40. c. because of nondisjunction, which yields an extra chromosome. d. most frequently in the offspring of men under the age of 40.

answer is c

Explanation:

down syndrome is caused by an error in cell division called nondisjunction. nondisjunction results in an an embryo

clinically, some people often have repeated allergies, eczema and respiratory infections or other parts of the infection, in this case, in addition to some routine tests such as tests for white blood cells, immunoglobulin series, lymphocyte subsets, etc., the five immune immunoglobulin tests are also necessary.

the dna molecules have a negative charge because of the phosphate groups in their sugar-phosphate backbone, so they start moving through the matrix of the gel towards the positive pole. power is turned on and dna fragments migrate through gel (towards the positive electrode).

explanation: