Chapter 4: Musculoskeletal System Flashcards
(167 cards)
ATP-PC System:
Energy system used for ATP production during high- intensity, short duration exercise such as sprinting 100 m.
ATP-PC Process:
Phosphocreatine decomposes and releases a large amount of energy that is used to construct ATP. There is 2-3 times more phosphocreatine in cells of muscles than ATP. This process occurs almost instantaneously, allowing for ready and available energy needed by the muscles. The system provides energy for muscle contraction for up to 15 sec.
The phospohagen system represents the most rapidly available source of ATP for use by the muscle. The energy system is able to function in the described manner since:
- It does not depend on a long series of chemical reactions.
- It does not depend on transporting the O2 we breathe to the working muscles
- Both ATP and PC are stored directly within the contractile mechanisms of the muscle.
ATP-PC is anaerobic or aerobic?
Anaerobic
Anaerobic Glycolysis System:
Energy system that is a major supplier of ATP during high intensity short duration activities such as 400 or 800 m runs.
Anaerobic Glycolysis Process:
Stored glycogen is split into glucose and through glycolysis, split again into pyruvic acid. The energy released during this process forms ATP. The process does not require O2. Anaerobic glycolysis results in the formation of lactic acid, which causes muscular fatigue.
Anaerobic Glycolysis is nearly 50% slower than the phosphocreatine system and can provide a person with 30-40 seconds of muscle contraction. The energy system is able to function in the described manner since:
- It does not require the presence of O2
- It only uses carbohydrates (glycogen and glucose)
- It releases enough energy for the resynthesis of only small amounts of ATP.
Aerobic Metabolism System:
Energy system used predominantly during low intensity long duration exercise such as running a marathon.
Aerobic Metabolism Process:
The O2 system yields by far the most ATP, but it requires several series of complex chemical reactions. This system provides energy through the oxidation of food. The combination of fatty acids, amino acids and glucose with O2 releases energy that forms ATP. This system will provide energy as long as there are nutrients to utilize.
Anatomical Position:
Erect posture of the body with the face forward, feet pointing forward and slightly apart, arms at the side, and palms forward with fingers and thumbs in extension.
Frontal Plane:
(Coronal plane) divides the body into anterior and posterior sections.
What motions occur in the frontal plane?
Abduction, Adduction, & Lateral Flexion
What axis is associated with the frontal plane?
AP axis
Sagittal plane:
Divides the body into right and left sections
What motions occur in the sagittal plane?
Flexion & Extension
What axis is associated with the sagittal plane?
ML axis
Transverse Plane:
Divides body into upper and lower sections
What motions occur in the transverse plane?
Medial & Lateral Rotation
What axis is associated with the transverse plane?
Vertical axis
Define Class 1 Lever:
The axis of rotation (fulcrum) between the effort (force) and resistance (load).
There are very few class 1 levers in the body.
Ex. Triceps brachii force on the olecranon with an external counterforce pushing on the forearm.
Ex. Seesaw
Define Class 2 Lever:
The resistance (load) is between the axis of rotation (fulcrum) and the effort (force).
The length of the effort arm is always longer than the resistance arm. In most instances gravity is the effort and muscle activity is the resistance. However, there are class 2 levers where the muscle is the effort when the distal attachment is on the weight bearing segment.
Ex. Wheelbarrow
Define Class 3 Lever:
The effort (force) is between the axis of rotation (fulcrum) and the resistance (load).
The length of the effort arm is always shorter than the length length of the resistance arm.
Permit large movements at rapid speeds and are the most common lever in the body
Ex. Shoulder Abduction with weight at the wrist is a class 3 lever.
Ex. Elbow Flexion
Define Fibrous Joints (Synarthroses):
Composed of bones that are united by fibrous tissue and are nonsynovial. Movement is minimal to none with the amount of movement permitted at the joint dependent on the length of the fibers uniting the bones.
Suture:
Fibrous Joint (Synarthroses)
Union of two bones by a ligament or membrane
Immovable joint
Eventual fusion is termed (synostosis)
Ex. sagittal suture of the skull