The Genus Latrodectus Includes Several Species, Including Spiders Commonly Called

question 19

Multiple Choice

The genus Latrodectus includes several species, including spiders commonly called widow spiders. The black widow is perhaps the most notorious member of this genus, and some species of black widows exhibit the familiar red hourglass on their ventral side. Black widows have large venom glands, and their bite can be harmful to humans. However, these bites very seldom lead to death in humans if proper medical treatment is provided. In comparison with females, adult male black widows are often gray or brown in color, rather than black, and they are only about half the size of females. As a result, they have smaller venom glands and tend to be less of a health concern. Black widows produce a neurotoxin called latrotoxin, and as the venom spreads through the body, it causes the release of neurotransmitters, including acetylcholine. Which of the following would work as an antidote for someone who was bitten by a black widow spider?

• A) a drug that blocks the sodium-potassium pump
• B) a drug that causes potassium gates to open
• C) a drug that blocks acetylcholine binding sites
• D) a drug that stimulates the release of calcium

---

Definitions:

Basilar Membrane

A membrane in the cochlea of the inner ear that plays a crucial role in sound vibration analysis and auditory processing.

Perilymph

The fluid that fills the space between the membranous labyrinth and the bone that encloses the inner ear, playing a key role in hearing and balance.

Bony Labyrinth

Part of the inner ear; contains the membranous labyrinth that forms the cochlea, vestibule, and semicircular canals.

Vestibule

An entrance or enclosed antechamber to a larger space or structure, like the entrance to the inner ear or to a building.