The answer would be the hardening of the myelin sheath. Multiple sclerosis is a chronic and inflammatory disease affecting the Central Nervous System and can cause a lot of symptoms like sensation changes, visual problems, severe fatigue and muscle weakness.
Answer:
Xylem tissue
Explanation:
The wood used to make chairs and musical instruments is made up of xylem plant tissue. Xylem tissue is a complex tissue that is made up of four primary cell types which include; xylem fibre, xylem parenchyma, trachea and tracheids. The xylem tissue together with phloem conducts water and solutes from the leaves to the other parts of the plant. Xylem tissue exists in both primary and secondary vascular tissues. The secondary xylem makes the mature stem and root in woody plants and it is produced as the plant develops in girths. The inner part of a large tree (known as heartwood) is made up of primary xylem that are dead but structurally strong, while within the older branches and the trunk of the tree is the external secondary xylem (known as sapwood) which functions by conducting water.
The same time, carbon dioxide that is dissolved in the blood comes out of the capillaries back into the air sacs, ready to be breathed out. Blood with fresh oxygen is carried from your lungs to the left side of your heart, which pumps blood around your body through the arteries.