The Contractile Cycle of the Heart Normally Originates from a Pacemaker

question 9

True/False

The contractile cycle of the heart normally originates from a pacemaker cell within the sinoatrial node.

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Definitions:

Salinity

The concentration of salts in water or soil, an important factor affecting the distribution of plant and animal life, as well as agricultural productivity.

Distribution

In ecology and biogeography, distribution refers to the way in which living organisms are spread out across geographical areas.

Terrestrial Biomes

Large community of plants and animals that occupy distinct regions of land, characterized by specific climate patterns, plant and animal species.

Representative Organisms

Species that serve as examples or proxies for a larger group of organisms, often used in research studies.