Module 5 - Anatomy: The Nervous System Flashcards
What will I learn in Module 5?
- The main parts of the nervous system
- The different sections of the brain and how it functions
- The structure and function of the spinal cord
- About nerve cells and how they transmit messages around the body
- About the effects of exercise on the nervous system
5.1 Anatomy - The Nervous System: What is controlled by the nervous system? It is like the CPU of the body that is responsible for all the actions and decisions that we make.
All your thoughts, communications, movements, and actions
5.2 What is the Nervous System?
- The nervous system is the system by which all our movements, whether voluntary or involuntary, are controlled.
- It transmits impulses and signals between the various parts of the body. If the nervous system fails we would be like vegetables, alive but unable to move or express ourselves.
5.2 The nervous system comprises of two parts:
- The Central Nervous System also called the CNS. This comprises of our Brain and Spinal Cord which are the main organs of the nervous system
- The Peripheral Nervous System is also known as the PNS. This comprises of nerves, which are groups of long tissues known as axons. The axons connect the various parts of the body to the CNS.
5.2 The nervous system is made up of:
nerves and special cells called the glial cells, along with blood vessels and connective tissue.
5.2 The nerve cells are also called
neurons and are the main receptors and transmitters of signals.
5.2 The glial cells, which are also called neuroglia, are cells that protect and support
the neurons in the nervous system and maintain the balance of the system throughout the body. They help to keep the neurons in place, provide nutrients to the neurons and protect neurons from one another. They also help to remove dead neurons and destroy disease-causing organisms.
5.3 Central Nervous System (CNS) - The CNS consists of two main organs.
The Brain and Spinal Cord
5.4 The Brain
- The brain is perhaps the most important organ of our body. It is like the conductor of an orchestra, it has to co-ordinate all the different parts and guide them to function properly at all times.
5.4 The Brain: The brain is encased at the top of our body inside the skull. What protects the brain?
The cranium protects the brain.
5.4 The Brain: The brain consists of three main parts:
- Cerebrum
- Cerebellum
- Brain Stem
5.4 The Brain: The Three Main Parts: Cerebrum:
front part of the brain and is also known as the front brain.
5.4 The Brain: The Three Main Parts: Cerebellum:
middle part of the brain and is also known as the mid brain.
5.4 The Brain: The Three Main Parts: Brain Stem:
lowest part of the brain that is connected to the spinal cord. It is also known as the hind brain.
5.4 The Brain: Cerebrum: This is divided into four different regions that take care of different functions.
- Frontal lobes 2. Parietal Lobes 3. Occipital Lobes 4. Temporal Lobes
5.4 The Brain: Cerebrum: This is divided into four different regions: Frontal lobes:
They are placed directly behind the forehead. This part of the brain controls your behavior, abstract thoughts, reasoning, problem solving, creativity, judgement, and co-ordination of movements, sense of smell, muscle movement, skilled movement, physical reaction, and sexual urges, among other things.
5.4 The Brain: Cerebrum: This is divided into four different regions: Parietal Lobes:
They lie behind the frontal lobe on the upper part of the brain. This part of the brain is responsible for tactility, stereognosis, response to the senses, they receive and process information about sensations of warmth, touch, movement from the body. In addition to this, they are also responsible for our ability to read and solve arithmetic problems.
5.4 The Brain: Cerebrum: This is divided into four different regions: Occipital Lobes:
As the name suggests, this part of the brain is concerned with sight and reading. It processes all that the eyes see. It is located towards the back of the brain. This lobe helps us to understand what we are seeing by linking it to the memory. Injury to the occipital lobes can lead to impaired vision and confusion.
5.4 The Brain: Cerebrum: This is divided into four different regions: Temporal Lobes:
It is located in the middle part of the bottom of the brain. This is the part of the brain that is responsible for auditory sensation. It helps us to hear by receiving information from our ears and processing it. It also plays an important role in creating and recollecting memories. This lobe helps us to identify sounds and the different pitches and helps us to understand speech. It also controls the sense of identity and some behaviors and emotions.
5.4 The Brain: The Cerebrum is divided into two hemispheres.
Left Hemisphere and Right Hemisphere
5.4 The Brain: The Cerebrum is divided into two hemispheres: Left Hemisphere:
Controls the right side of our body and performs logical and academic functions. Left brain functions include analysis of thoughts, language, and reasoning, understanding of written information, numbers, science, and mathematics.
5.4 The Brain: The Cerebrum is divided into two hemispheres: Right Hemisphere
Controls the left side of our body and performs creative functions. It is concerned with spatial and sequential functions, analyzing and interpreting nonverbal communication. Its functions also include intuition, insight, creativity, etc.
5.4 The Brain: The two hemispheres of the brain are connected with the Corpus Callosum, which is located under the cortex. Corpus Callosum transmits…
all neural communications between the left and the right brain.
5.4 The Brain: Cerebellum
This is the middle brain and is located towards the back of the brain and under the cerebrum. It is the most easily recognizable part of the brain, mainly because of its shape and location. It is responsible for all voluntary movements, balance, and synchronization of muscles and body. It helps us with tasks such as running, walking, typing, etc. as well as maintaining balance.
5.4 The Brain: Brain Stem
This is the lowest part of the brain. It connects the cerebrum to the top of the spinal cord. All the information to and from the body is sent to the cerebrum and the cerebellum through the brain stem.
5.4 The Brain: Brain Stem: It is formed of the following:
Mesencephalon, Metencephalon, Medulla Oblongata
5.4 The Brain: Brain Stem: Mesencephalon:
also called the mid brain.
5.4 The Brain: Brain Stem: Metencephalon:
which forms a part of the pons. It is located above the medulla oblongata and connects the upper part of the brain to the lower part. It functions as a storage area before the messages are relayed to the various parts of the brain. It is the transmitter of the messages. It also has an important role to play in our sleep. The REM sleep originates from the pons.
5.4 The Brain: Medulla Oblongata:
it is a part of the spinal cord that extends into the pons. This is the area of the brain through which all information passes.
5.4 The Brain: The functions of the brain stem include:
controlling arousal, breathing, digestion, heart rate, blood pressure and carrying information between the spinal cord and the brain. It is also responsible for autonomous functions of the body.
5.5 The Spinal Cord:
The second major organ of the CNS is the spinal cord. It is a long cable-like structure that runs from the base of the skull all the way down through the vertebral column. The spinal cord in human beings is roughly about 17 inches long. It is protected by the vertebral column which is composed of 31 bony segments called the vertebrae. Each segment has a pair of spinal nerves emerging from it. The entire length of the vertebral column is about 27 inches.
5.5 The Spinal Cord: It is composed of nerve tissues or neurons including:
Somatic Motor Cells, Autonomic Motor Cells, Transmission Neurons, Interneurons.
5.5 The Spinal Cord: Nerve tissues or Neurons 1/4: Somatic Motor Cells:
transmitters for skeletal muscles