Capillaries are one cell thick and so this makes them very thin. capillaries are also arranged in networks known as capillary beds, and thus multiple capillaries are spread over a large area.
The fight or flight system is a reaction that the body undergoes when put in an either stressful or frightening situation. It includes both the nervous and endocrine system.
The sympathetic division of the peripheral nervous system is used in this response as the sympathetic nervous system works up the body, increases the rate of breathing, heart rate, dilates the pupils, produce more sweat and slow the digestion rate. This reaction happens in the flight or fight system.
A. dermal tissue inhibits water loss.
Answer:
D. Aids
Explanation:
Aids is one of the most deadliest diseases in the world. When you contract aids, it's designed to infect the cells that try to destroy it, it's a whole zombie apocalypse in your body and you don't even know it.
It attacks and weakens the immune system, and our immune system defends our bodies against infections, but HIV is extremely strong and it over powers the system, I'm not sure if there's an immune system strong enough to fight HIV or aids.
The Mitral valve which is also known as left atrioventricular prevents blood movement from left ventricle to left atrium.
Explanation:
- Human heart is four chambered.
- Two of these are receiving chambers known as atria and the other two are distributing chamber known as Ventricles.
- Atria are superior chambers and ventricles are inferior chambers.
- The heart has four valves broadly grouped as Atrioventricular valves and Semi lunar valves.
- Atrioventricular valves allows flow of blood from atria to ventricle. These are tricuspid valve and bicuspid valve.
- Semi-lunar valves allow blood to pass out of the heart. These include the pulmonary and aortic valves.
- The pulmonary valve allows blood to flow from right ventricle to the heart while aortic valve allows blood to flow from left ventricle to the Aorta.
- The Tricuspid valve located between the right atrium and right ventricle allows blood to flow from right atrium to the right ventricle.
- The Bicuspid valve ( Mitral valve) located between the left atrium and left ventricle allows the blood flow from left atria to left ventricle.
- Valves maintain the unidirectional flow of blood and thus prevent its back flow.