Answer:
Disease spread can affect air travel really badly because it can be so easy for anyone to get infected with how crowded airports can be. This usually results in extra safety steps taken up to cancelled flights due to closed borders. A popular example of this is the current pandemic crisis.
Explanation:
The <span>ability of leukocytes to move in and out of blood vessels in order to reach sites of inflammation or tissue destruction is known as leukocyte extravasation (also called <em>diapedesis</em><u />).</span>
A Multi-Celled organism has many cells (more than one). Examples would be plants, humans and animals/mammals.
A Single-Celled organism only has one cell that makes up it's entire self. Examples would be bacteria and archaea.
The correct answer is A, parathyroid gland.
The parathyroid hormone is secreted by the parathyroid gland which <span>inhibits osteoblasts, stimulates osteoclasts,</span> reduces the calcium output by the kidneys and promotes absorption of the calcium by the small intestines. Calcitonin, secreted by the thyroid gland, also works to a similar effect.
