Answer:
A brain ventricle is a cavity in the brain with an open channel leading to it.
Explanation:
The brain and spinal cord are encased and protected by three layers of tissue, all called meninges. The outermost layer is called the dura mater, and covers both the brain and spinal cord. On either side of this layer, where it crosses or penetrates into these organs, are two extensions that look like small tubes coming from under a tent. These extensions are called cranial nerves because they come out on either side of the head just below its most prominent part - hence "cranial".
The second statement best explains the type of blood vessel and the function of these vessels' valves - <span>These are veins, which prevent the backflow of blood because the walls have little muscle to pump blood back to the heart.
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Veins are large blood vessels which carry blood back to the heart. <span>Veins have a system of valves to prevent back-flow.</span>
Answer:
algia and dynia
Explanation:
There both about pain in the body
4.a
5.d
those are the only ones i'm 100% sure about.