Final answer:
The glands that produce mucus as a lubricant during sexual intercourse are known as vestibular glands in females and bulbourethral glands in males.
Step-by-step explanation:
The glands that produce mucus used as a lubricant during sexual intercourse are the vestibular glands, also known as Bartholin's glands or greater vestibular glands, in females. These glands produce a thick mucus that maintains moisture in the vulva area. In males, a similar lubricating function is served by the bulbourethral glands, also called Cowper's glands, which secrete a fluid that lubricates the urethra and helps to neutralize any urine it may contain before ejaculation occurs.