Nervous Tissue🧠 Flashcards
What is the function of nervous tissue?
to provide rapid and precise communication between different parts of the body via the action of neurones
The nervous system includes various organs throughout the body, what are these?
brain, spinal chord, receptors of complex sensory organs and the nerves that link the nervous system with all of our other organs and systems in the body
Where do organs of our nervous system receive information from? What do they do with this information?
-Receive info from both their internal and external environment
-process that info and then send out necessary signals to initiate a response
The Nervous system is divided into what two main divisions
Peripheral Nervous System
Central Nervous System
How do the peripheral nervous system and central nervous system bring about a response?
-Peripheral NS delivers sensory info to the CNS
-where it is processed and the signals are sent back out to PNS
-This sends out required signals to initiate an appropriate response.
What two divisions can your Peripheral Nervous System be functionally divided into?
-Somatic Nervous System
-Autonomic Nervous System
What is the function of the Somatic NS?
regulates voluntary control over our skeletal muscle (conscious movement)
What is the function of the Autonomic Nervous System?
Controls involuntary subconscious functions like heartbeat and breathing
Our Autonomic nervous system can be further sub-divided into what two divisions?
Sympathetic NS
Parasympathetic NS
What is the parasympathetic nervous system?
Referred to as the rest and digest system, regulates less urgent process i.e.
-digestion, waste disposal, production of bodily fluids
What is the sympathetic nervous system?
Branch that responds when body needs immediate action, Regulates fight or flight
What function does the parasympathetic and sympathetic nervous system have in common?
Both regulate smooth and cardiac muscle contractions
What is a way of thinking about the parasympathetic and sympathetic nervous system?
Parasympathetic regulates basal rate of all these processes, keeping things ticking along and then the sympathetic system can come in and up the ante, increasing the rate of these functions in times of need
What are neurones?
The main functional cells of the nervous system
What are neurones specifically designed to do?
send signals and communicate with our organs and tissues using electrical impulses
What are neuroglia/ glial cells?
What are their function?
They are support cells
They have have various different roles that include;
-providing support
-protection,
-providing nutrient
-providing immune protection to our neurones
What are neurones specialised for?
Intercellular Communication- communication between cells
-Do neurones live for long?
-What is the metabolic rate of neurones like and why?
-They are long lived cells
-high metabolic rate because the generation and propagation of action potentials, so these electrical impulses place significant energy demands on our neurones
What is the structure of neurones like?
Neurones display substantial variation in size and shape but all have the same basic structure
What are dendrites?
What is their role?
What happens at this site?
-Highly branched processes that extend away from the cell body.
-These play a key role in intracellular communication.
-This is the site at which neurones will receive info from other cells or sensory receptors
What are the size of neurone cell bodies like?
Large cell bodies significantly larger than other cells like neuroglia
All neurones have a single axon, what is the function of these axons?
The axon is designed to rapidly propagate electrical Impulses/ action potentials from one part of the body to another
Describe the size of the single axons of neurones?
some of these can be extremely long, i.e. in the peripheral nervous system some axons can be up to a meter in length
Describe the axon terminals?
At the axon terminal, the axon branches into smaller branches, and at the foot of these branches you have what is known as Terminal Boutons
What do TERMINAL BOUTONS do?
form communication junctions with other cells in the pathway and these communication junctions are often referred to as synapses