Let’s start the introduction of the Human Brain
Central Nervous System
The CNS consists of the brain and the spinal cord. The brain and the spinal cord are protected by the skeleton – the brain by the cranium and the spinal cord by the vertebral column.
Brain
The study of the brain is called Neurology.
- The membrane of the brain = Meninges
- Cell/unit of brain = Neuron
- Weight of the brain in male = 1450 grams.
- Weight of brain in female = 1350 grams.
- A mineral present in the brain = sodium
- The hard covering layer of brain = Cranium
Human Brain Structure
The brain is broadly divided into three regions:
- Forebrain
- Midbrain
- Hindbrain
Forebrain
It includes the cerebrum, Thalamus, and Hypothalamus. The main thinking part of the brain is Forebrain.
Cerebrum
The cerebrum is the dome-shaped roof of the brain.
- It is the largest part of the
- It is also called an intelligent brain.
- Different areas of the cerebrum have different
For example, The cerebrum has sensory areas where information is received from the sense organs called receptors. Similarly, the cerebrum has motor areas from where instructions are sent to the various muscles of the body called effectors to do the various jobs.
There are specific regions in the cerebrum for each kind of stimulus and response.
Structure of lobes of the human brain
For examples,
The occipital lobe is the region for sight, e., visual reception.
The temporal lobe is the region for hearing, e., auditory reception.
The frontal lobe is the region for speech, facial muscular activities and higher mental
The parietal lobe is the region for Smell, taste, touch, and conscious
Olfactory lobes in the fore-brain lie below the cerebrum. They contain olfactory receptors which are the organs of
Thalamus
It controls the function of the Nose, Tongue, and Skin.
Hypothalamus
It regulates the temperature of our bodies. It controls emotion, hunger, hate, love, feeling, mood, anger, pain.
Midbrain
It connects the forebrain to the hindbrain. The midbrain controls reflex movements of the head, neck, and trunk in response to visual and auditory stimuli.
Hindbrain
It consists of three centers called the cerebellum, pons, and medulla.
Cerebellum: It lies at the roof of the hindbrain. This region controls the coordination of body.
- It is called also called a little brain and tree of life.
- Functions of the Cerebellum are speaking power control, balancing of body, and muscle movement control.
- Effect of alcohol in the Cerebellum part.
Pons lies just above the medulla and takes part in regulating respiration. It regulates the breathing rate. It transfers the pain signal of the spinal cord to the hypothalamus.
Medulla oblongata lies at the floor of the hindbrain and continues into the spinal cord. It is also the regulating center for swallowing, coughing, sneezing and vomiting.
Functions of Brain
- The brain receives information-carrying impulses from all the sensory organs of the
- IT responds to the impulses brought in by sensory organs by sending its own instructions to the muscles and glands causing them to function
- It correlates the various stimuli from different sense organs and produces the most appropriate and intelligent.
- The brain coordinates the activities so that the mechanisms and chemical reactions of the bodywork together
- The brain stores information so that behavior can be modified according to past experience. This function makes the brain the organ of thought and
Spinal Cord
It is a cylindrical structure and a part of the central nervous system. It is made up of nerves that supply information to think. The spinal cord is active when the brain is busy. It is also called the 2nd brain of the human body.
- It begins in continuation with the medulla oblongata and extends
- The spinal cord is enclosed in a bony cage called vertebral
- A total of thirty-one pairs of spinal nerves arise from the spinal
Functions of Spinal Cord
- The main center of reflex action is the Spinal cord.
- It is concerned with the conduction of nerve impulses to and from the
Peripheral Nervous System
It consists of the cranial and spinal nerves along with their branches.
- Cranial nerves arise from the brain and spread throughout the
- There are twelve pairs of cranial
- Spinal Nerves arise from the spinal cord along most of its length and spread throughout the
- There are 31 pairs of spinal nerves – eight in the neck region, twelve in the chest, five in the abdominal region, five in the hip region, and one in the coccyx region. Coccyx which is the last bone of the vertebral
Autonomic Nervous System (ANS):
It means ‘self-governing nervous system’:
- The autonomic nervous system is called the visceral nervous
- It lays outsides and parallels to CNS.
- NS consists of a pair of a chain of nerves and ganglia found on both sides of the vertebral
- The autonomic nervous system can be classified anatomically and functionally into the sympathetic and parasympathetic nervous systems.
Dopamine
It is a green color chemical in which neurons transfer the signal from the brain to all organs and all organs to the brain.
- Dopamine is called protein hormone.
- Dopamine is called Neutro Transmetre.
- It is also called the satisfaction hormone.
- It is also called the love and feeling hormone.
Some important question of Human Brain
- Explain the difference between Cerebrum and Cerebellum.
Answer: The Cerebrum is a part of the forebrain. It is the site of our faculties such as reasoning, learning, intelligence, personality, and memory.
The cerebellum is a part of the hindbrain. It helps in maintaining the posture and balance of the body. The cerebellum is enabled us to make precise and accurate movements.
- What is a reflex action? Explain with the help of an example.
Answer: The rapid, automatic response to a stimulus that is not under the voluntary action of the brain is called reflex action. Example: Moving our hands away on touching a hot plate.
- What is the function of our nervous system?
Answer: The functions of our nervous system are:
- The function of the nervous system is to coordinate the activities of our body.
- It receives information from its surroundings, processes it, interprets it, and then responds accordingly.
- It helps all other systems of our body to work together.
- How does the human nervous system work? Explain.
Answer: When the sense organ in our body is affected, it sends the message to the brain in the form of electrical impulses through the sensory neurons. The brain analyses this message and decides the action to be taken. When the brain sends out instructions to the muscles of the concerned body parts through motor nerves and the concerned body part acts accordingly.
- What is a neuron? Draw a labeled diagram of a neuron.
Answer: The unit which makes up the nervous system is called a neuron.
- What is the voluntary nervous system? Explain the working of the voluntary nervous system for example.
Answer: The voluntary nervous system is a system that helps us to take voluntary actions that are under the conscious control of the brain. Example: If a student is getting late for school and sees his watch. He starts walking fast. In this process, the eyes see the time and send the information to the brain through the sensory nerves. When the brain analyses the information and sends the instructions to walk faster to the muscle of our legs through the motor nerves. The muscles of the legs act accordingly and make the student walk faster.
- What is the autonomic nervous system? What is its function?
Answer: The autonomic nervous system means a self-governing nervous system. Its function is to control and regulate the functions of the internal organs of our body involuntarily.
- What are the major organs of the nervous system?
Answer: The major organs of the nervous system are the brain, spinal cord, and nerves.