The red blood cell lifespan in circulation is between 80 and 120 days.
a. true
b. false

The correct answer is a. True

Explanation:

The red blood cells in humans are originated in bone marrow and are called erythrocytes. It's main function is to carry oxygen to the tissue. It has biconcave shape. It contains a protein named hemoglobin which can bind to oxygen present in the lungs and carry to other organs of the body.

Red blood cells lack nucleus and is produced by a process called erythropoiesis in bone marrow. In this stem cells converts into erythrocytes with in 7 days and released into circulation where it lives about 80-120 days after that they are destroyed in spleen by spleenic macrophages.

answer: the answer is d.

explanation: this is because when you exercise you make your muscle produce a certain liquid, that does not evaporate it.   also when you exercise you do not reduce muscle fiber.   and it does not really control your twitch that much.

answer:

to with mild choking in an adult or child over 1 year old: encourage them to keep coughing to try to clear the blockage. ask them to try to spit out the object if it's in their mouth. don't put your fingers in their mouth to them as they may bite you accidentally.

explanation: