Human Brain And Its Parts
Transcript
00:00hi kids today we will learn about the human brain it's the main part of our
00:08central nervous system the human brain is the most complex organ the human
00:18brain weighs only about three pounds and is estimated to have about 100 billion
00:26cells and the brain is mostly made up of cells called neurons neuron is a
00:35specialized cell that lets it transmit signals from one neuron to the other in
00:42the form of electromagnetic waves this is a cell body that has a nucleus inside
00:49it these are dendrites that receive messages
00:54in the form of electrical signals and this is axon where the message in the
01:01form of electrical signals travels and passes to the dendrites of the next
01:07neurons these are axon terminals that join with the next neurons electrical
01:15signal keeps on moving from one neuron to the other till it reaches its
01:20destination so the brain is a control center of the body that controls every
01:29action and reaction of our body it's the brain that tells us if we are hungry and
01:37should eat something it's the brain that tells us that something is hot and we
01:43should not touch it it's the brain that makes us smile makes us walk play dance
01:51dream cry imagine and just everything let's learn in detail the parts of the
02:00brain brain lies well protected inside the heart bony skull there is some space
02:08between the brain and the skull and it's filled with cerebrospinal fluid this
02:15fluid acts as a cushion for the delicate brain the brain is a wrinkled
02:22structure that resembles a walnut now let's learn the main parts of our brain
02:29the brain mainly consists of three parts cerebrum cerebellum and medulla or
02:37brain stem cerebrum this part of the brain is called cerebrum it's the largest
02:46part of the brain you can see this part is responsible for learning memory
02:52thinking reasoning and consciousness all the actions that we take knowingly or
03:00with our full consciousness are known as voluntary actions and all these
03:05voluntary actions are controlled by our cerebrum next is the cerebellum this
03:15part of the brain situated below the cerebrum and it's called cerebellum it
03:23is also known as the smaller brain and its main function is to make sure that
03:29the balance of our body is maintained that is it keeps us in balance while we
03:36are walking we are sitting we are dancing or while we are exercising that
03:42is it ensures smoothness in our movements
03:49medulla or the brain stem this part of the brain connects the brain to the
03:55spinal cord medulla is responsible for the involuntary actions of our body that
04:04is actions that we do not take knowingly like sneezing our heartbeat our
04:12breathing movement in the stomach and many other functions that happen in our
04:18body and we do not take these actions knowing they are just happening on their
04:24own these functions are controlled by medulla of the brain our brain is
04:30divided into two hemispheres left and right the left hemisphere and the right
04:39hemisphere does a different job it is responsible for analytical activities it
04:47analyzes the information which is collected by the right brain and the
04:52right brain is more responsible for visual activities that is it collects
04:58the visual information if someone gets a stroke in the left hemisphere of his
05:06brain the right side of his body stops working and if there is an injury to the
05:13right hemisphere the left side of the body stops working this is why one half
05:21of the face may droop when a person has had a stroke in the general population
05:2895% of people are right-handed which means that the left hemisphere is more
05:35dominant in case of left-handers the right hemisphere is more dominant now
05:43let's learn about our spinal cord it is the main nerve of our body it's an s
05:51nerve that starts from the brainstem or medulla it's thick as a finger and is
06:00about 45 inches long the s shape of the spinal cord gives it more strength the
06:10role of the spinal cord is to transfer the signals from all body parts to the
06:16brain and also transfer the signals from the brain to all the parts of the
06:23body a lot many nerves branch out from the spinal cord to different parts of
06:31the body information from the brain goes out through the spinal cord to different
06:40body parts to make them work almost all parts of the body send signals to the
06:47brain through the spinal cord but only in the case of vision and hearing signals
06:56do not go through the spinal cord but they go directly to the brain that's why
07:02people who are completely paralyzed that is are unable to move their limbs and
07:09other body parts are still able to see and hear the spinal cord lies inside the backbone or the
07:20vertebral column which is made up of small bones called vertebrae and there are 26 vertebrae the
07:29vertebral column for example if someone is pricked by a pin or any sharp object the
07:39nerve endings in that portion of the body at once passes the message to the spinal cord and that is
07:47through the sensory nerves and spinal cord then passes this message to the brain brain interprets
07:55the message and sends the order back to that portion of the body and it is at once moved
08:04away this is why we quickly remove our hand if it gets hurt from something hot or something sharp
08:13if in any way we are going to get hurt we get away quickly these are called reflex actions
08:24if something comes too close to our eyes our eyes immediately shut this too is a reflex action all
08:40this sending and receiving of messages is too fast it's so unimaginably fast that even before
08:49taking a sudden action messages have already passed between the body parts and the brain
08:55so kids today we learned about our brain spinal cord and what our reflex actions
09:08now you may go ahead and take a quiz to learn more bye-bye