Listening

resting mebrane potential

RMP

muscle tissue

nervous tissue 

RMP- inside of the cell -outside the cell 

muscle and neuron ( RMP) 
phospholipid bilayer- 

they cannot freely passthrough 

sodium 

chemical gradient

ATP pump

3 sodium 

2 potassium

charge different across the 

pumpout 3 sodium

inside -slightly negative charge compare inside 

sodium and potassium pump

compare to the outside 

negative five differnt 

more positive charge 

channel is close 

muscle cell ( neuron ) the door is slightly ( sneakly ) even more negatively inside the cell 

electrical gradient 

electricalchemical gradient 

at rest neuron-stimulate the cell 

muscle cell calcum - muscle cell will contract 

Quiz

 intracellular fluid

Answer and Explanation: At resting potential, higher concentrations of K+ is found in the intracellular fluid (ICF), and a higher concentration of Na+ is found in the extracellular fluid (ECF).

Motor neuron

 https://www.kenhub.com/en/library/anatomy/motor-neuron

Neuron

•  Neurons are the cells considered to be the basis of nervous tissue.
•  Nervous tissue is composed of two types of cells, neurons and glial cells.
• Neurons are electrically active and release chemical signals to target cells.
• Glial cells, or glia, are known to play a supporting role for nervous tissue.
• Neuron -  responsible for the electrical signals that communicate information about sensations, and that produce movements in response to those stimuli, along with inducing thought processes within the brain.
• The main part of a neuron is the cell body, which is also known as the soma (soma = “body”).
• processes of the neuron are dendrites, which receive information from other neurons at specialized areas of contact called synapses.

• Types of Neurons- 

1. Unipolar neuron, 
2. Bipolar neurons, 
3. Multipolar neurons 

• Unipolar cells have only one process emerging from the cell.
• Bipolar cells have two processes, which extend from each end of the cell body, opposite to each other.  found in olfactory epithelium
• Multipolar neuron-have one axon and two or more dendrites (usually many more).

• Glial cells, or neuroglia or simply glia, are the other type of cell found in nervous tissue.
• Glial cell is supporting cells, and many functions are directed at helping neurons complete their function for communication.
• Six types of glial cell four are found in CNS and two are found in PNS.
• CNS glia              PNS glia                  Basic function

1. Astrocyte                 Satellite cell                     Support
2. Oligodendrocyte   Schwann cell                  Insulation, myelination
3. Microglia -  -                                       Immune surveillance and phagocytosis
4. Ependymal cell        -                                        creating CSF

Glial cells support neurons in the central nervous system are 

1. by maintaining the concentration of chemicals in the extracellular space.
2. removing excess signaling molecules, 
3. reacting to tissue damage, and contributing to the blood-brain barrier (BBB).

• Nutrient molecules, such as glucose or amino acids, can pass through the BBB, but other molecules cannot.
•   Myelin is a lipid-rich sheath that surrounds the axon and by doing so creates a myelin sheath that facilitates the transmission of electrical signals along the axon. 
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The posterior horn is responsible for sensory processing and contain the axons of sensory neurons and the cell bodies of interneurons. 

Dictionary

What does being integrated mean?

Things or people that are integrated have been brought together, so that they live or work together

Important notes chapter 12

• Nervous tissue, present in both the CNS and PNS.
• Nervous tissue, contains two basic types of cells: neurons and glial cells.
• Neurons are cells and therefore have a soma.
• There is one important process that every neuron has called an axon, which is the fiber that connects a neuron with its target. 
• Another type of process that branches off from the soma is the dendrite.
• These two regions within nervous system structures are often referred to as gray matter (the regions with many cell bodies and dendrites) or 
• white matter (the regions with many axons). 
• But white matter is white because axons are insulated by a lipid-rich substance called myelin. 
• The distinction between gray matter and white matter is most often applied to central nervous tissue, which has large regions that can be seen with the unaided eye.
• A brain removed during an autopsy, with a partial section removed, shows white matter surrounded by gray matter.
•  Gray matter makes up the outer cortex of the brain. (credit: modification of work by “Suseno”/Wikimedia Commons)
• A localized collection of neuron cell bodies in the CNS is referred to as a nucleus.
• In the PNS, a cluster of neuron cell bodies is referred to as a ganglion. 
• Nucleus it is the center of a cell, where the DNA is found; and it is a center of some function in the CNS.
• Terminology applied to bundles of axons also differs depending on location. 
• A bundle of axons, or fibers, found in the CNS is called a tract whereas the same thing in the PNS would be called a nerve.
• Nervous system function 
• The nervous system is involved in receiving information about the environment around us (sensation) and generating responses to that information (motor responses) 
• The nervous system can be divided into regions that are responsible for sensation (sensory functions) and for the response (motor functions).
• Sensory input needs to be integrated with other sensations, as well as with memories, emotional state, or learning (cognition).
• The sensory functions of the nervous system register the presence of a change from homeostasis or a particular event in the environment, known as a stimulus.
• The senses we think of most are the “big five”: taste, smell, touch, sight, and hearing.
• The stimuli for taste and smell are both chemical substances (molecules, compounds, ions, etc.), 
• Touch is physical or mechanical stimuli that interact with the skin,
•  sight is light stimuli, and hearing is the perception of sound, which is a physical stimulus similar to some aspects of touch.
• Those five are all senses that receive stimuli from the outside world, and of which there is conscious perception.
• Additional sensory stimuli might be from the internal environment (inside the body), such as the stretch of an organ wall or the concentration of certain ions in the blood. for example can detect high sodium level in blood or high potassium level in blood .
• Response. The nervous system produces a response on the basis of the stimuli perceived by sensory structures. 
• An obvious response would be the movement of muscles, such as withdrawing a hand from a hot stove, but there are broader uses of the term. (motor response). 
• The nervous system can cause the contraction of all three types of muscle tissue. For example, skeletal muscle contracts to move the skeleton, cardiac muscle is influenced as heart rate increases during exercise, and smooth muscle contracts as the digestive system moves food along the digestive tract.
• Responses also include the neural control of glands in the body as well, such as the production and secretion of sweat by the eccrine and merocrine sweat glands found in the skin to lower body temperature.
•  Voluntary responses are governed by the somatic nervous system and 
• Involuntary responses are governed by the autonomic nervous system.
• Stimuli that are received by sensory structures are communicated to the nervous system where that information is processed. ( eye , ear, touch, taste ,smell) 
• Controlling the Body ( Somatic nervous system and autonomic nervous system) 
• somatic nervous system (SNS) is responsible for conscious perception and voluntary motor responses.
• Voluntary motor response means the contraction of skeletal muscle.
• The autonomic nervous system (ANS) is responsible for involuntary control of the body, usually for the sake of homeostasis. (blood pressure, heart rate , respiration, temperature) 
• The role of (ANS)the autonomic system is to regulate the organ systems of the body, which usually means to control homeostasis. 
• The enteric nervous system (ENS) is responsible for controlling the smooth muscle and glandular tissue in your digestive system. It is a large part of the PNS.and is not dependent on the CNS. It is sometimes valid, however, to consider the enteric system to be a part of the autonomic system because the neural structures that make up the enteric system are a component of the autonomic output that regulates digestion. 
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