6 - Muscle and nervous tissue Flashcards
What are the three main muscle tissues?
Striated, non striated and cardiac
Striated skeletal muscle (or voluntary)
Striated tissue is under conscious control, enabling us to move our bones
Striated skeletal muscle tissue is striated
The striating are caused by the density of overlapping protein filaments and it gives it a striped appearance
Skeletal muscles are usually under voluntary control
Non striated (smooth or involuntary)
Non-striated tissue is concerned with many internal body processes and functions, such as peristalsis in the digestive system
Not striated because the protein filaments are not as dense as in cardiac and skeletal muscle
Smooth muscle is found in organs such ad in the gastrointestinal system and the arteries
Smooth muscle is usually under involuntary control
Cardiac tissue
Only found in the heart wall. It is not under conscious control and never tires
Cardiac tissue is striated but has a unique structure called an intercalated disk
The disks are special intercellular junctions that allow electrochemical impulses to be conveyed across the tissue
What are the characteristics of muscle tissue which contribute to muscle functioning?
Contractibility
Irritability
Extensibility
Elasticity
What is contractibility?
The ability to shorten and thicken
What is irritability?
The ability to respond to stimuli created by nerve impulses
What is extensibility?
The ability to stretch
What is elasticity?
The ability to return to its original shape following contraction
What are the two types of nervous tissue?
Neurones and neuroglia
What does nervous tissue consist of?
Nervous tissue consists of neutrons to form the nervous system
What is the function?
The function is to rapidly regulate and integrate the activities of the different part of the body and can be found in the brain, spinal cord and the nerves.
What are the two kinds of cells?
Nerve cells/neurons and neuroglia
Nerve cells/neurons (with properties known as
A neurone is a specialised nerve cell that receives stimuli, converts it to a nerve impulse and transmits this to other neurones, muscles and glands.
The conducting units of the system
Neurones occur as single cells and in groups in certain areas of the body, such as the spinal cord
A neurone consists of a cell body, an axon and many dendrites
Neurones receive stimuli at the dendrites. A nerve impulse travels along the axon to the terminals. These form connections with other neurones, muscles or glands.
Neuroglia
These support and protect the neurones
They are smaller and more numerous than neurones, forming over 50% of brain tissue
Special connecting and supporting cells
