Muscular System Flashcards
Types, Functions, etc. (22 cards)
What are muscles?
Tough elastic tissues made of cells called muscle fibres
What parts of the body do muscles work?
Limbs, lungs and other parts of the body; give the body bulk and shape
3 Main types of muscle:
Skeletal, smooth, cardiac
Skeletal muscle:
A.K.A voluntary/striated (striped) - large cross-banded fibres. Ends mostly joined to bones by tendons of tough connective tissue. Many nuclei e.g., forms legs, arms, chest. They hold bones together and pull on them to make them move
Smooth muscle:
A.K.A involuntary muscles (they work automatically) Small fibres, not striped (single nucleus) e.g., found in intestines, stomach, blood vessels, bladder. Rhythmically contract to move food, blood etc.
Cardiac muscle:
Forms the walls of the heart. Striped, but works automatically. Has 1 nucleus per fibre (like smooth muscle)
Fuel for muscles: source
Energy from glucose in the blood. Glucose combines with oxygen, releasing energy.
Fuel for muscles: what does muscle activity produce?
Heat, lactic acid, water and carbon dioxide wastes removed by blood
Fuel for muscles: exercise effect
Vigorous exercise increases muscle’s need for oxygen + blood, producing panting and a rapid heart rate
Masseter muscle
Chews
Trapezius muscle
Holds head back
Deltoid muscle
Lifts arm
Triceps muscle
Straightens arm
Biceps muscle
Bends arm
Latissimus dorsi muscle
Strengthens back
Intercostals muscle
Move ribs
Gluteus maximus muscle
Used in standing up
Rectus femoris muscle
Straightens leg
Gastrocnemius muscle
Used in walking
How do muscles work?
Muscles work in pairs (can pull but not push). E.g., bending and straightening the arm involves biceps and triceps (antagonistic pair)
Antagonistic pair: biceps
When the biceps contracts the triceps relaxes and the arm bends
Antagonistic pair: triceps
When the triceps contracts the biceps relaxes and the arm straightens
