What substances present in semen (not in the sperm itself) allow sperm to successfully make their long journey through the “hostile environment of the vagina,” into the uterus and into the fallopian tubes? list at list five substances and the glands that produce them.

evidence and logical support is essential for a scientist to do in order to maintain credibility. this is because no one can believe without any logic and without any evidence.hence a scientist can maintain credibility by proving himself and by answering logically so experiments prove very beneficial. logical hypothesis give conclusion which is acceptable. therefore, there are two main factors to maintain credibility by a scientist is evidence and logical support.

it is called the mitotic spindle