Answer: A closed circulatory system and an excretory system consisting of tubular nephridia
Explanation:
Destruction of myelin will affect the nerve and there will be the less conduction of electrical impulses from the brain to other parts of the body and the nerve signal sent to the brain are delayed. These damaged nerve areas form sclerosis which disrupts the signalling capacity of the nerve. This may occur due to genetic defects, infectious agents, auto immune reactions and trauma.
Answer:
A. mitochondria is the powerhouse of the cell
Answer: An Organ System
Explanation: Vascular plants have two distinct organ systems: a shoot system, and a root system. The shoot system generally grows above ground, where it absorbs the light needed for photosynthesis. The root system, which supports the plants and absorbs water and minerals, is usually underground.