Assignment 2

Question 1

In human anatomy, what is an articulation?

Answer 1

In human anatomy, what is an articulation? It is where two bones meet

Question 2

What are the three types of articulations based on function or movability?

Answer 2

The three types of articulations are :

Synarthroses which do not allow movement (such as those in the skull)

Amphiarthroses are joints allow more movement than synarthroses but movement is still minimal (an example is the pubic symphysis)

Diarthroses – allow the most amount of movement

Question 3

Define the three types of muscle tension.

Answer 3

Concentric muscle tension is when your agonist muscles are actually using more force (or torque) than the externally produced forced (torque) pushing against it. Your antagonist muscles are passively stretching in this case.

Eccentric muscle tension is when you have an externally produced force (or torque) that is greater than the force produced by your agonist muscles. Take for example a cup you are slowly placing down onto the table. The gravity and weight of the cup are exerting a force onto your arm, and your arm is exerting a force as well. Yet, the muscle fibers in your arm are not putting as much force on this cup. This means that while your muscles are actually still engaged and producing tension, they are still lengthening (it is actively controlled lengthening of muscle fibers).

Isometric muscle tension is when the externally produced force (or torque) is equal to the force (or torque) produced by the muscle.

In this case imagine you are hold a cup in the air in a stable position. Your muscles are actually producing a force that is equal to the force that gravity is putting onto the mass of that cup

Question 4

Describe the following in reference to muscles:

Origin, Insertion, Agonist, Antagonist

Answer 4

Describe the following in reference to muscles:
If a muscle connects to two bones, this means it has two tendons that connect to these bones.

Origin – the origin of a muscle is actually referring to the tendon of origin that is normally on the more proximal, larger, less moveable bone.

Insertion – the insertion of a muscle refers to the tendon of insertion – this tendon is usually on the more distal, less stable, and smaller bone that moves more when the muscle is contracted

Agonist – this term refers to muscles. It is the muscle (via shortening – concentric contractions, or lengthening – eccentric contractions) that causes a motion.

Antagonist – This is the muscle that is either passively contracted or passively lengthened when an agonist muscles moves. The term antagonist can only be talked about relative to an agonist.