Researchers at Vanderbilt University in Nashville, Tennessee, have found that while you are asleep, the only body part that remains active is the ear.
The heart pumps blood containing oxygen to every part of your body. At the same time, it pumps the blood without oxygen back through the lungs where it picks up new oxygen, This cycle is repeated every time your heart beats, 24 hours a day, everyday. Lungs.
The cardiac muscle does not relax and prepare for the next heartbeat simply by ceasing contraction; it occurs in an active process called Lusitropy.
Heart: The heart is a key element of the cardiovascular system and its continuous activity is required for the maintenance of normal blood pressure that ensures the blood supply to all parts of the body.
The brain never truly sleeps – only parts of it. Understanding how the brain and eyes generate our 24-hour cycle of sleep and wake is now an active and exciting area of neuroscience research across the world.
Once the soft tissues have fully decomposed, all that remains is the skeleton. The skeleton and teeth are much more robust. Although they undergo a number of subtle changes after death, they can remain intact for many years.
The SCN is located in the hypothalamus. The SCN is sensitive to signals of dark and light. The optic nerve in your eyes senses the morning light. Then the SCN triggers the release of cortisol and other hormones to help you wake up.
Decompensation progresses over a period of minutes even after the pulse is lost. Even when vascular collapse is the primary event, brain and lung functions stops next. The heart is the last organ to fail.
The five vital organs in the human body are the brain, the heart, the lungs, the kidneys, and the liver.
Of all the organs in the human body, the heart is without a doubt the hardest worker. Beating an average of 72 times per minute, it's responsible for pumping 2,000 gallons or more of blood through the body each day.
Your heart is an incredibly hardworking organ. In five minutes, it will pump five litres of blood around your body. After an hour, it will have pumped 300 litres in 4,200 heartbeats.
Unlike other muscle cells in the body, cardiomyocytes are highly resistant to fatigue. True, cardiomyocytes are primarily powered by mitochondria (the energy house of the cell), similar to your other muscles. However, cardiomyocytes have as much as 10 times the density of mitochondria, skyrocketing their energy output.
3-5am the time of the Lungs and again, this is the time where the body should be asleep.
Liver: 1am-3am
As you can see from this schedule, 1-3am is 'liver time'.
The skin is the body's largest organ.
Although some patients who have a diseased portion of their liver removed are unable to regrow the tissue and end up needing a transplant. Researchers from Michigan State University believe blood clotting factor fibrinogen may be responsible.
The brain is the only organ in the human body that cannot be transplanted.
The brain and nerve cells require a constant supply of oxygen and will die within a few minutes, once you stop breathing. The next to go will be the heart, followed by the liver, then the kidneys and pancreas, which can last for about an hour. Skin, tendons, heart valves and corneas will still be alive after a day.
Your heart stops beating. Your brain stops. Other vital organs, including your kidneys and liver, stop. All your body systems powered by these organs shut down, too, so that they're no longer capable of carrying on the ongoing processes understood as, simply, living.
Visions and Hallucinations
Visual or auditory hallucinations are often part of the dying experience. The appearance of family members or loved ones who have died is common. These visions are considered normal. The dying may turn their focus to “another world” and talk to people or see things that others do not see.
Your body's biological clock is based on a 24-hour day and controls most circadian rhythms. These rhythms affect a variety of functions including body temperature (represented as the white line on the chart above). Melatonin - a hormone released by the pineal gland - helps you feel sleepy once the lights go down.
Let's take a look at the liver. According to the Organ Clock it is the most busy during 1-3am at night.