The Embryonic Yolk Sac, the Liver, and the Bone Marrow

question 75

Multiple Choice

The embryonic yolk sac, the liver, and the bone marrow are sites where

• A)T lymphocytes complete maturation.
• B)immune responses to antigen occur.
• C)stem cells give rise to immature lymphocytes.
• D)antigen is filtered from the blood.
• E)antigen is filtered from tissue fluid.

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Definitions:

Chelicerae

Paired appendages near the mouth of arachnids, such as spiders and scorpions, used for feeding.

Spiders

Arachnids characterized by eight legs, chelicerae with fangs that inject venom, and the ability to produce silk, often used to make webs for catching prey.

Subduing Prey

The act of overpowering or bringing under control an organism intended as food by a predator.

Mandibles

Jaw or jawbone, specifically the lower jaws in vertebrates, but in arthropods, they refer to either of a pair of mouthparts used for biting and chewing.