Lecture 3 - Neuromuscular Components Flashcards
What are the two systems necessary for movement?
Nervous system (control) and muscular system (muscle)
What is the function of the nervous system during movement?
To dictate muscle activity, nerves are the “controllers”
What is the function of the muscular system during movement?
To create movement via contraction/relaxation of the muscle fibers, muscles are the “motors”
What are the divisions of the nervous system?
Central Nervous System (CNS) and Peripheral Nervous System (PNS)
What are the two types of cells in the nervous system?
Neurons and glia
What are the neurons?
Nerve cells. Receive, process and output information. The basic functional unit of the nervous system
What are glia?
Support cells. Nurture and repair neurons. Insulate, support and nourish neurons. Greek for glue.
What are the components of the central nervous system?
The brain and spinal chord
How large is the brain?
1.3 kg (3 lbs)
How many neurons are in the brain?
> 100 billion
How many glia cells are in the brain?
> 1 trillion
How long is the spinal chord?
~44 cm (20 in)
How much does the spinal chord weigh?
35-40 g (0.08 lbs)
What are the components of the peripheral nervous system?
Neurons and glia that are not entirely contained within the brain/spinal chord
What are the divisions of the peripheral nervous system?
The autonomic nervous system and the somatic nervous system
What is the function of the autonomic nervous system
To control smooth muscle of internal organs and glands
What is the function of the somatic nervous system?
To send sensory information to the CNS and motor info to the muscles
Which division of the peripheral nervous system is essential to movement?
The somatic nervous system
What are the basic components of a neuron?
The nucleus, dendrite, cell body, axon, and presynaptic terminal
What is the function of a nucleus in a neuron?
It is the genetic center of the cell.
What is the function of the dendrite in a neuron?
To receive information from all other neurons
What is the function of a cell body in a neuron?
To sum information from dendrites and other terminals
What is the function of an axon in a neuron?
To transmit information from the cell body
What is the function of the presynaptic terminal in a neuron?
To attach to other neurons to relay information
What are the types of neurons?
Sensory neurons, motor neurons, and interneurons.
What are sensory neurons?
Neurons that deliver information to the CNS from endings on the surface of the body and within muscles and tendons. They give us information about the body relative to the environment
Are sensory neurons afferent or efferent?
Sensory neurons are afferent. They carry info towards the CNS
What are motor neurons?
Neurons that are connected to muscles cells which cause muscle contractions (movement.) They are necessary to perform any type of voluntary movement
Are motor neurons afferent or efferent?
Motor neurons are efferent. They carry info away from the CNS
What are interneurons?
Neurons with no direct role in ‘sensing” the internal or external environment or causing the contraction of the muscles. They are necessary for performing processing functions (ex. memory) and account for the majority of neurons.
Where are sensory neurons located?
The PNS
Where are interneurons located?
The CNS
Where are motor neurons located?
The CNS (axon and PS terminal) and PNS (cell body and dendrites)
What is the ratio of glial cells to neurons?
10:1
What are myelin?
Key glia cells that cover the axon of many neurons to speed up transmission of nerve impulses.
How many skeletal muscles do humans have?
> 600
How do skeletal muscles work?
By pulling on bones to act as levers.
What dictates what the muscle can do?
Its size and shape
What is the basic structure of a muscle?
Muscle -> muscle bundle (fascicle) -> muscle fiber
What are the basic components involved in muscle contraction?
The myosin complex with ATPase, actin helix, tropomyosin, troponin, ATP, calcium, and magnesium
What are the types of connective tissue?
Loose connective tissue, fibrous connective tissue, blood, cartillage, adipose, and bone.
Which type of connective tissue is important for movement?
Bone
What is the function of the skeleton?
To act as levers for movement. Bones are a major contributor to the structure of the human body.
How many bones are there in the human body?
~206
What are levers?
A simple machine for moving an object.
What are the basic components of a lever?
A rigid bar, a resistance to be moved (load), a force to move the resistance (effort), and a pivot point (fulcrum)
What in the human body serves as a rigid bar in the lever?
Bones
What in the human body serves as the pivot point in a lever?
Joints
What in the human body serves as a movement force in a lever?
Muscle force
What in the human body serves as a resistance force in a lever?
Many things such as weight
What type of levers are humans?
Third class - good for speed, evolutionary trait to run from predators.
What are the divisions of the autonomic nervous system?
Sympathetic and parasympathetic
What is the sympathetic system?
Fight or flight
What is the parasympathetic system?
Rest and digest
What is an afferent neuron?
Carries information to the brain
What is an efferent neuron?
Carries information away from the brain
Where does muscle contraction occur?
At the sarcomeres
What is is actin?
The thinner filaments involved in muscle contraction
What is myosin?
The thicker filaments involved in muscle contraction
What are the components involved in the sliding filament theory?
ATP, tropomyosin, and calcium
