Answer:
Oligodendrocytes in the brain and spinal cord and Schwann cells in the peripheral nervous system are specialized types of glia that build the myelin sheaths that surround neurons.
Explanation:
Myelin sheath is an insulating layer, which covers neurons. It is made up of protein and fatty substances. This myelin sheath permits electrical impulses to move very fast along the neurons.
Answer: A scientific theory is best explained as concepts that join well-supported and related hypotheses. In science, a theory is supported by a broad range of OBSERVATIONS, EXPERIMENTS, and DATA
Explanation:
<span> B. lack vascular tissue. Mosses don't have a true vascular system such as stems, roots and leaves. So, they need to absorb water directly from the soil. </span>In plants vascular system came from bundles of tissues that makes a plant grow tall. Mosses lack these bundles.
The conduction system contains pacemaker cells, nodes, the Purkinje fibers, and the bundle of His.
<h3>What is the conduction system of the heart?</h3>
The conduction system of the heart refers to the the system of cells and fibers which enables conduction of nerve impulse which enables the contraction of the heart.
The conduction system of the heart consists of:
- Sinoatrial node
- Atrioventricular node
- Atrioventricular bundle (bundle of His)
- Purkinje fibers
Therefore, the conduction system of the heart coordinates the contraction of the heart.
Learn more about conduction system of the heart at: brainly.com/question/18983307
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