• 4 months ago
Transcript
00:00Dear Tim and Moby,
00:28How many organs do we have and what do they all do?
00:31Curious Galen
00:32I think he's talking about human organs
00:38What the what?
00:46Uh...
00:49Kinda looks like a cryosleep chamber
00:51Anyway, scientists who study anatomy, the body's structure, say that we have about 80
00:58It's hard to pin down an exact number because the definition isn't so precise.
01:03An organ is just a part of the body that carries out specific functions,
01:08like how the lungs take in oxygen and expel carbon dioxide.
01:13All organs are made of tissues, groups of similar cells.
01:17Some organs will be familiar to you, like the heart.
01:21Others you may never have heard of, like the pineal gland.
01:25It's a tiny structure in the brain that controls your sleep cycle.
01:28Organs might be as spread out as blood vessels or-
01:33Sorry, got a little carried away there.
01:35Point is, we have dozens of organs that handle thousands of different tasks,
01:39and they all have to work together to keep your body going.
01:42To keep it all straight, scientists categorize organs into 11 systems.
01:47Each system is responsible for one or more complex tasks, like moving around or breathing.
01:55We'll start with one you've probably heard of, the skeletal system.
01:59It gives the body shape, providing support and protection for other organs.
02:03The skeleton is made up of more than 200 bones.
02:07It also includes cartilage to cushion our joints where bones meet,
02:11plus ligaments that connect bone to bone and tendons that connect bone to muscle.
02:16When a muscle flexes, it pulls the tendon, which in turn pulls the bone.
02:20That's why the muscular system is often grouped together with the skeletal.
02:25Together, they're known as the locomotor system, because they let us move around.
02:29Voluntary actions like running, talking, and sitting are handled by skeletal muscles.
02:35Other muscles work automatically, like the ones in your stomach that help move food along.
02:39Speaking of which, the stomach is part of the digestive system, which breaks down our food.
02:45It starts with our mouth, where we take in and take out food.
02:48It continues to our stomach and intestines, which extract and absorb nutrients,
02:53and ends when we get rid of the, uh, solid waste in the bathroom.
02:59The excretory system removes another kind of waste product.
03:03It takes toxic chemicals out of our blood and dissolves them in water.
03:08We get rid of this stuff when we pee.
03:12Yep, blood is carried around by our circulatory system.
03:15Yep, blood is carried around by our circulatory system.
03:18The heart is the motor of this system, pumping blood everywhere it's needed.
03:23And blood vessels are the tubes that take it there.
03:26All of the other body systems depend on a fresh supply of blood.
03:31The respiratory system uses blood to pick up oxygen from our lungs.
03:35And the heart pumps out that oxygen-rich blood to our different cells.
03:40They use the oxygen for energy, and in the process, produce a waste gas called carbon dioxide.
03:46The blood takes that back to the lungs to be exhaled.
03:50The lymphatic system relies on circulation, too.
03:53It consists of a network of tubes, similar to blood vessels.
03:57Its main role is to absorb fluid that builds up between our cells.
04:02It returns this fluid back to our bloodstream.
04:05But it also plays an important role in our immune response.
04:08Lymphatic organs create white blood cells.
04:11They help destroy germs that can make us sick.
04:16Circulation helps out the endocrine system, too.
04:19Its organs, or glands, produce hormones.
04:22Those are chemical messengers that tell organs, tissues, and cells to do different things.
04:28Hormones get where they need to go through your blood vessels.
04:31For example, after you eat, your pancreas releases a hormone called insulin.
04:36It tells your cells to absorb sugar from the blood.
04:39Some endocrine organs are also part of our reproductive system.
04:43That's basically what humans use to, well, make more humans.
04:48If I were female, my reproductive system would look like this.
04:53Uh, moving on.
04:55Our nervous system includes the brain, spinal cord, and a network of long nerves.
05:01Those carry electrical signals to tissues and organs throughout the body.
05:05Signals from sense organs to your brain let you see,
05:08feel, hear, taste, and all that other good stuff.
05:13Signals from your brain to your skeletal muscles let you move around.
05:16And signals inside the brain carry all of your thoughts, feelings, and dreams.
05:23Last but not least is our integumentary system.
05:26It includes our skin, hair, and nails.
05:30All our other systems are protected by this flexible covering.
05:36Yeah, the human body is a pretty amazing machine.
05:39Maybe even more amazing than this contraption of yours.
05:43How do I get out, anyway?
05:44This button?
05:48Cryo sleep mode activated.
05:57Oh.
05:59Oh.
06:00Ugh.
06:03How long have I been asleep?
06:06Three weeks.
06:08Huh.