Muscular System Flashcards
What are the three main types of muscles in the body?
Cardiac, smooth, and skeletal muscles.
Where is cardiac muscle found?
The Heart
What is the function of cardiac muscle?
It aids blood flow through the heart by contracting involuntarily.
Where can smooth muscle be found?
In the digestive tract, blood vessels, stomach, uterus, and bladder.
What is a unique characteristic of smooth muscle?
It contracts in all directions and works involuntarily.
What are the functions of smooth muscle?
It aids digestion and helps distribute blood.
What is the role of skeletal muscles?
They work voluntarily to aid movement.
What is the role of the deltoid muscle?
It causes abduction of the shoulder, moving the arm away from the body.
What is the function of the trapezius muscle?
It allows movement of the head and shoulder blades.
What are antagonistic pairs of muscles?
Muscles that work in pairs, where one muscle (agonist) contracts while the other (antagonist) relaxes to produce movement.
Give an example of an antagonistic muscle pair.
Biceps (agonist) and triceps (antagonist).
What are the origin and insertion points of muscles?
The origin is the fixed point of a muscle, and the insertion is where the muscle attaches to the moving bone.
What is an isotonic contraction?
A muscle contraction where the muscle changes length, such as lifting or lowering a weight.
What are the two types of isotonic contractions?
Concentric (muscle shortens) and eccentric (muscle lengthens).
What is an isometric contraction?
A static contraction where the muscle does not change length, such as holding a plank.
What are the characteristics of Type 1 muscle fibres?
Dark red, slow contraction speed, slow to fatigue, and suited for endurance activities like long-distance running.
What are the characteristics of Type 2 muscle fibres?
White, very fast contraction speed, quick to fatigue, and suited for explosive activities like sprinting and weightlifting.
How can training affect muscle fibre performance?
Low-intensity, high-repetition training improves Type 1 fibres, while high-intensity, low-repetition training improves Type 2 fibres.
Why are antagonistic pairs important for movement?
They allow smooth and controlled movement by enabling one muscle to pull while the opposing muscle relaxes to balance the action.
What is the role of the agonist in an antagonistic pair?
The agonist is the prime mover that contracts to create movement.
What is the role of the antagonist in an antagonistic pair?
The antagonist relaxes or lengthens to allow the movement initiated by the agonist.
Give an example of an antagonistic pair in the arm.
The biceps (agonist) and triceps (antagonist) during elbow flexion.
What happens to the biceps and triceps when straightening the arm?
The triceps become the agonist, contracting to straighten the arm, while the biceps act as the antagonist, relaxing.
Which antagonistic pair is involved in knee extension?
The quadriceps (agonist) and hamstrings (antagonist).
What action do the hamstrings perform in an antagonistic pair?
The hamstrings cause flexion of the knee joint when they act as the agonist.
