Which Substance Is Capable of Closing Pain Gates

question 143

Multiple Choice

Which substance is capable of closing pain gates?

• A) dopamine
• B) norepinephrine
• C) endorphins
• D) estrogens

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Definitions:

Semen

A fluid containing sperm and other secretions from the male reproductive system, involved in reproduction.

Urethra

The tube that carries urine from the bladder to the outside of the body, and in males, also serves as a conduit for semen.

Vagina

The muscular tube leading from the external genitals to the cervix of the uterus in females, part of the reproductive system.

Stratified Squamous Epithelium

A type of tissue composed of multiple layers of flat cells found in areas of the body subject to friction and wear, such as the skin, mouth, and esophagus.