Lancelets is the group of chordates that has a notochord and includes separate males and females.
Lancelet exhibits the four basic characteristics of phylum Chordata. It has a dorsal nerve, a notochord, a post annul tail, and pharyngiall gill slit.
Jawless fish, cartilaginous fish, and bony fish have notochord when they were still young but it was replaced by a vertebral column as they mature.
<span>Lancelets are included in the subphylum cephalochordata. Cephalochordates are gonochoristics. It means that the sexes are separate. Both sperm and eggs cells are released in the water where fertilization occurs.</span>
<span> if a mother is a </span>carrier<span> for colorblindness (X</span>+Xc), and a father has normal vision X+Y, then their sons have a 50% chance of colorblindness because they inherit their X chromosome from their<span> mother and their Y chromosome from their father.</span>