Your Research Project Involves Sea Cucumbers, a Poorly-Understood Group of Echinoderms.You

question 54

Multiple Choice

Your research project involves sea cucumbers, a poorly-understood group of echinoderms.You are trying to determine whether they block polyspermy by changing membrane potential like sea urchins do.In the chart below, you have counted the number of embryos that complete normal development after fertilization in either normal or low-sodium artificial sea water (ASW) , for each of three sets of experiments.Looking over your data, what do you conclude?

• A)Sea cucumbers appear not to block polyspermy the same way as sea urchins, which use an influx of Na⁺ that changes the membrane potential.
• B)Sea cucumbers appear not to block polyspermy the same way as sea urchins, which use an outflow of Na⁺ that changes the membrane potential.
• C)Sea cucumbers appear to block polyspermy the same way as sea urchins, via an influx of Na⁺ that changes the membrane potential.
• D)Sea cucumbers appear to block polyspermy the same way as sea urchins, via an outflow of Na⁺ that changes the membrane potential.

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Definitions:

Pathogenic Proteins

Abnormal proteins that can cause disease by disrupting normal cellular functions.

Local Anesthetic

A type of medication used to induce absence of sensation in a specific area of the body, preventing pain.

Parasite

An organism that lives on or in a host organism and gets its food at the expense of its host.

Offspring

The progeny or descendants of a parent or parents; the young born to an organism.