The "Pacemaker" of the Heart Is the __________ Node

question 21

Multiple Choice

The "pacemaker" of the heart is the __________ node.

• A)atrioventricular
• B)Purkinje
• C)diastolic
• D)systolic
• E)sinoatrial

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Definitions:

Sieve-Tube Members

Specialized elongated cells in the phloem of vascular plants, which transport sugars and other organic nutrients.

Vascular Cambium

A layer of actively dividing cells in plants that produces secondary xylem (wood) and phloem, contributing to the thickness of stems and roots.

Mycorrhizae

Symbiotic associations between fungi and plant roots, enhancing nutrient and water absorption for the plant while the fungus benefits from access to carbohydrates.

Roots

The part of a plant that typically lies below the surface of the soil, responsible for anchoring the plant and absorbing water and nutrients.