Answer: 1. Blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. As the atrium contracts, blood flows from your right atrium into your right ventricle through the open tricuspid valve.
2. Plasma is the main component of blood and consists mostly of water, with proteins, ions, nutrients, and wastes mixed in. Red blood cells are responsible for carrying oxygen and carbon dioxide. Platelets are responsible for blood clotting. White blood cells are part of the immune system and function in immune response.
3.Within the bone marrow, all blood cells originate from a single type of unspecialized cell called a stem cell. When a stem cell divides, it first becomes an immature red blood cell, white blood cell, or platelet-producing cell.
4. Epinephrine and norepinephrine, hormones secreted by the adrenal medulla, raise blood pressure by increasing heart rate and the contractility of the heart muscles and by causing vasoconstriction of arteries and veins. These hormones are secreted as part of the fight‐or‐flight response.
Answer:
Adenoids
Explanation:
They help the immune system fight off viruses and bacteria. They become less important as we age.
I believe the answer would be C
Answer: slightly cooler than
Explanation:
The testes are the male gonads. These are found in a loose pouch which is called as the scrotum behind the penis. The testes are responsible for production and storage of sperms which are the male gametes, and fluids which makes up the composition of the semen in males. The testes being the sperm factor functions efficiently when the temperature of the scrotum is slightly cooler than the rest of the body.
