Jeans/Genes and Other Overplayed Puns

The staff at Jupiter Scientific presents a collection of biology jokes, though Daily Scan will let you decide which are genuinely humorous. The jeans/genes pun plays prominently on the list:

Q: What is the fastest way to determine the sex of a chromosome?
A: Pull down its genes.

Q: What was the biologist wearing on his first date … ?
A: Designer jeans.

For those who miss the puns' meanings, Jupiter Scientific has kindly provided explanations — though be warned that there is arguably nothing less funny than discussing the meaning behind an already unfunny joke.

HT: SciCareers.info