Which does not add substances to seminal fluid?

Seminal fluid is a liquid that transports sperm out of the body during ejaculation. It is produced by a number of glands, including the prostate gland, the seminal vesicles, and the bulbourethral glands. The prostate gland adds the following substances to seminal fluid:

- Citric acid: This substance helps to lower the pH of the vagina, making it more hospitable to sperm.

- Fibrinogen: This protein helps to form a clot around the sperm, which helps to protect them from the acidic environment of the vagina.

- Prostaglandins: These hormones help to relax the muscles of the uterus, making it easier for the sperm to reach the fallopian tubes.

The seminal vesicles add the following substances to seminal fluid:

- Fructose: This sugar provides energy for the sperm.

- Glycerophosphocholine: This substance helps to protect the sperm from damage.

- Prolactin: This hormone helps to stimulate the production of sperm.

The bulbourethral glands add the following substance to seminal fluid:

- Mucous: This substance helps to lubricate the urethra, making it easier for the sperm to travel through.

The only option that does not add any substances to seminal fluid is the epididymis. The epididymis is a long, coiled tube that connects the testes to the vas deferens. It is responsible for storing sperm and helping them to mature.