Muscular System

Question 1

Muscles & Tendons

Answer 1

• muscles are attached to bones via tough bands called tendons
• when a muscle contracts, it applies force to the bone it’s attached to which makes the bone move
• muscles are found in pairs around a joint

Question 2

Antagonistic muscles

Answer 2

• pairs of muscles that work against each other
• one muscle contracts (shortens) while the other relaxes (lengthens) and vice versa
• one muscle pills the bone in one direction and the other pulls in the opposite direction, causing movement at the joint

E.g. bicep and tricep

Question 3

Measuring force applied by a muscle

Answer 3

Moment= force x perpendicular distance

Moment in Nm
Force in N
Perpendicular distance in m

• When a force acts on something that has a pivot, it creates a “turning effect” know as moment
• The arm works as a lever with the elbow as a pivot
• This means when a force acts on the arm, there’s a moment

Question 4

Pivot

Answer 4

The point around which a rotation happens

Question 5

Lever

Answer 5

A bar attached to a pivot

Question 6

Perpendicular distance

Answer 6

The distance at a right angle from the pivot to the line of force