The nervous tissue
The majority of the nervous system is tissue made up of 2 classes of cells: neurons & neuroglia.
Neurons: The nerve cells communicate within the body by transmitting electrochemical signals. The cell body is the roughly round part of a neuron that carries the nucleus mitochondria, and most of the cellular organelles.
The main function of the nervous system- it controls the regulatory and communicating system in the body. It is the center of all mental activity including thought, learning and memory.
Brain- The brain is a soft wrinkly organ that weighs 3lbs and is located inside the cranial cavity, where the skull surrounds and protects it. The brain functions as consciousness, memory, planning, and voluntary actions. It also controls lower body functions such as maintenance of respirations, heart rate, blood pressure and digestion.
Spinal cord- The spinal cord is a long thin mass of bundled neurons that carry info. through the vertebral cavity of the spine beginning at the mycelia oblongata of the brain on its end and continuing inferiorly to the lumbar region of the spine. It functions as the main conduit of nerve signals to the body from the brain.
Nerves- Nerves are bundles of axons in the peripheral nervous system that acts as info. highways to carry signals.
Meninges
The meninges are the protective coverings of the central nervous system (CNS). They consist of three layers: the dura mater, arachnoid mater, and pia mater.
Dura mater-The dura mater, which means “tough mother,” is the thickest, toughest, and most superficial layer of meninges. Made of dense irregular connective tissue, it contains many tough collagen fibers and blood vessels. Dura mater protects the CNS from external damage, contains the cerebrospinal fluid that surrounds the CNS, and provides blood to the nervous tissue of the CNS.
Arachnoid-The arachnoid mater, which means “spider-like mother,” is much thinner and more delicate than the dura mater.
Pia mater-The pia mater , which means “tender mother,” is a thin and delicate layer of tissue that rests on the outside of the brain and spinal cord. Containing many blood vessels that feed the nervous tissue of the CNS, the pia mater penetrates into the valleys of the sulci and fissures of the brain as it covers the entire surface of the CNS.
cerebrospinal fluid
The space surrounding the organs of the CNS is filled with a clear fluid known as cerebrospinal fluid (CSF). CSF is formed from blood plasma by special structures called choroid plexuses. The choroid plexuses contain many capillaries lined with epithelial tissue that filters blood plasma and allows the filtered fluid to fill in the empty space surrounding the brain.
The nervous system has 3 main functions: sensory, integration, and motor.
3 interesting facts about the nervous system:
1. There are more nerve cells in the human body than stars in the milky way.
2. A new born loses about 1/2 of it nerve cells before their even born.
3. There are 100 billion neurons in your brain alone.
The majority of the nervous system is tissue made up of 2 classes of cells: neurons & neuroglia.
Neurons: The nerve cells communicate within the body by transmitting electrochemical signals. The cell body is the roughly round part of a neuron that carries the nucleus mitochondria, and most of the cellular organelles.
The main function of the nervous system- it controls the regulatory and communicating system in the body. It is the center of all mental activity including thought, learning and memory.
Brain- The brain is a soft wrinkly organ that weighs 3lbs and is located inside the cranial cavity, where the skull surrounds and protects it. The brain functions as consciousness, memory, planning, and voluntary actions. It also controls lower body functions such as maintenance of respirations, heart rate, blood pressure and digestion.
Spinal cord- The spinal cord is a long thin mass of bundled neurons that carry info. through the vertebral cavity of the spine beginning at the mycelia oblongata of the brain on its end and continuing inferiorly to the lumbar region of the spine. It functions as the main conduit of nerve signals to the body from the brain.
Nerves- Nerves are bundles of axons in the peripheral nervous system that acts as info. highways to carry signals.
Meninges
The meninges are the protective coverings of the central nervous system (CNS). They consist of three layers: the dura mater, arachnoid mater, and pia mater.
Dura mater-The dura mater, which means “tough mother,” is the thickest, toughest, and most superficial layer of meninges. Made of dense irregular connective tissue, it contains many tough collagen fibers and blood vessels. Dura mater protects the CNS from external damage, contains the cerebrospinal fluid that surrounds the CNS, and provides blood to the nervous tissue of the CNS.
Arachnoid-The arachnoid mater, which means “spider-like mother,” is much thinner and more delicate than the dura mater.
Pia mater-The pia mater , which means “tender mother,” is a thin and delicate layer of tissue that rests on the outside of the brain and spinal cord. Containing many blood vessels that feed the nervous tissue of the CNS, the pia mater penetrates into the valleys of the sulci and fissures of the brain as it covers the entire surface of the CNS.
cerebrospinal fluid
The space surrounding the organs of the CNS is filled with a clear fluid known as cerebrospinal fluid (CSF). CSF is formed from blood plasma by special structures called choroid plexuses. The choroid plexuses contain many capillaries lined with epithelial tissue that filters blood plasma and allows the filtered fluid to fill in the empty space surrounding the brain.
The nervous system has 3 main functions: sensory, integration, and motor.
3 interesting facts about the nervous system:
1. There are more nerve cells in the human body than stars in the milky way.
2. A new born loses about 1/2 of it nerve cells before their even born.
3. There are 100 billion neurons in your brain alone.