The Vascular Cambium Is Initiated by Cells

question 49

Multiple Choice

The vascular cambium is initiated by cells:

• A)of the pericycle.
• B)of the endodermis.
• C)in the center of the vascular cylinder.
• D)opposite the protoxylem poles.
• E)between the primary xylem and primary phloem.

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Definitions:

Histamine

A compound involved in local immune responses, as well as regulating physiological functions in the gut and acting as a neurotransmitter.

Antibody-Mediated Immunity

The aspect of the immune system involving antibodies produced by B cells that target and neutralize foreign pathogens.

Cell-Mediated Immunity

An immune response that does not involve antibodies but rather the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen.

Extracellular Antigens

Antigens that exist outside the cells, which can trigger an immune response in the body.