Chapter 4: Musculoskeletal System

NPTE Practice

What is the ATP-PC system?

A system used for ATP production during high-intensity, short-duration exercises, such as sprinting 100 meters.

What decomposes and releases a large amount of energy that is used to construct ATP?

phasphocreatine

Where is phosphocreatine mostly located?

in the cells of muscles

There are 2 to 3 more _________ in cells of muscles than _____.

phophocreatine; ATP

How long does the ATP-PC system provide energy for a muscle contraction?

15 seconds

What does the phosphagen system represent?

the most rapidly available source of ATP for use by muscles

The phosphagen system is available to function in the described manner since:

it does not depend on a long series of chemical reactions or transporting the oxygen we breathe to the working muscles, and both ATP and PC are stored directly within the contractile mechanisms of the muscle

What is anaerobic glycolysis?

an energy system that is a major supplier of ATP during high intensity, short duration activities such as sprinting 400 to 800 meters

Describe the process of ATP formation in anaerobic glycolysis.

Stored glycogen is split into glucose, and through glycolysis, split again into pyruvic acid. The energy released during this process forms ATP. The energy released during the process forms ATP and does not require oxygen

The anaerobic glycolysis system is nearly ________ % slower than the phosphocreatine system.

50

How long does the anerobic glycolysis system keep a muscle contraction?

30 to 40 seconds

The anaerobic glycolysis system is able to function due to:

it not requring the prescence of oxygen, only using carbohydrates (glycogen and glucose), and it releases enough energy for the resynthesis of only small amounts of ATP

What is the aerobic system predominantly used for?

During low-intensity, long-duration exercise such as running a marathon

How is aerobic metabolism provide energy?

through the oxidation of food. The combination of fatty acids, amino acids, and glucose with glucose with oxygen that forms ATP.

The aerobic metabolism system will provide energy as long:

as their are nutrients to utilize

What is the frontal plane?

A plane that divides the body into anterior and posterior sections.

What motions usually occur in the frontal plane?

abduction/adduction

The motions that occur in the frontal plane occur around what type of axis?

anterior-posterior axis

What is the sagittal plane?

plane that divides the body into right and left sections

What motions occur in the sagittal plane? Around what axis?

flexion and extension; medial lateral axis

What is the transverse plane?

plane that divides the body into upper and lower sections.

What motion occurs in the transverse plane? Around what axis?

medial and lateral rotation; vertical axis

What is a class I lever?

lever that has the axis of rotation between the effort (force) and resistance (load)

What is an example of a class I lever?

The triceps brachii force on the olecranon with an external counterforce pushing on the forearm or a seesaw

What is a class 2 lever?

lever with the resistance (load) between the axis of rotation and the effort (force)

In a class 2 lever, the length of the _____ arm is always longer than the _________ arm

effort; resistance

Describe a class 2 lever arm (pg.52).

gravity is the effort, and muscle activity is the resistance

What is an example of a class 2 lever?

wheelbarrow

What is a class 3 lever?

a lever with effort (force) between the axis of rotation (fulcrum) and the resistance (load).

In a class 3 lever, the length of the __________ arm is always shorter than the length of the __________ arm

effort; resistance

What are examples of class 3 levers?

shoulder abduction with weight at wrist; elbow flexion

What is the most common type of lever in the body?

class 3

What is another name for a fibrous joint?

synarthroses

What are fibrous joints composed of?

bones that are united by fibrous tissue and are nonsynovial

Describe movment of fibrous joints.

it is minimal to none with the amount of movement permitted at the joint, dependent on the length of the fibers uniting the bones

What are the three types of fibrous joints?

God Said So (gomphosis, suture, syndesmosis)

What is gomphosis?

two bony surfaces that connect at a peg hole

What are the only gomphosis joints in the body?

teeth and corresponding sockets in the mandible/maxilla

Gomphosis joints are two bony surfaces that connect at a ______________

peg in a hole

What is the fibrous component of the gomphosis joint?

periodontal membrane

What is a suture?

joint that unites two bones by a ligament or membrane

What type of joint is a suture?

immovable joint

What is the eventual fusion of sutures called?

synostosis

What is an example of a suture?

the sagittal suture of the skull

What is a syndesmosis joint?

bone connected by a dense fibrous membrane or cord

Describe the movement of a syndesmosis joint.

very little motion

What is an example of syndesmosis joints?

the tibia and fibula with interosseous membrane

What is another name for a cartilaginous joint?

amphiarthroses

What are cartilagenous joints?

joints that have hyaline cartilage or fibrocartilage that connect the bone to another

What type of joints are cartilagenous joints?

slight moveable joints

What are two types of cartilagenous joints?

syncondrosis and symphysis

What is a synchondrosis?

hyaline cartilage; cartilage that adjoins two ossifying centers of bone

What is the primary purpose of synchondrosis?

provides stability during growth

Synchondrosis may ________ to syntosis once growth is completed

ossify

What type of movement occurs in cartilaginous joints?

slight motion

What is an example of a symphysis joint?

pubic symphysis

What is a symphysis joint?

joint located at the midline of the body

A symphysis joint contains two bones connected by ____________ and covered with _________________

fibrocartilage; hyaline cartilage

What type of motion occurs at a symphysis joint?

slight motion

What is a synnovial joint?

joint that provides free movement between the bones they join

What are the five distinguishing characteristics of a synovial joint?

joint cavity, articular cartilage, synovial fluid, synovial membrane, and fibrous capsule

What joints are the most vulnerable to energy?

synovial joints

What are the three types of synovial joints?

uniaxial joints, biaxial joints, and multiaxial joints

What is a unixial joint?

a joint that has one motion around a single axis in one plane of the body

What are examples of a uniaxial joint?

hinge (ginglymoid) and pivot (trochoid)

What is an example of a hinge joint?

elbow joint

What is an example of a pivot joint?

antantoaxial joint

What is a biaxial joint?

movement that occurs in two planes and around two axes through the convex/concave surfaces

What are two types of biaxial joints?

condyloid and saddle

What is an example of a condyloid joint?

metacarphalangeal joint of a finger

What is an example of saddle joint?

carpometacarpal joint of the thumb

What is a multiaxial joint?

joint where movement occurs in three planes and around three axes

What are the two types of multi-axial joints?

plane (gliding) and ball and socket

What is an example of a ball of socket joint?

hip joint

What is an example of a plane (gliding) joint?

carpal joints

What are free nerve endings located?

in the joint capsule, ligaments, synovium, and fat pads

One type of free nerve endings is sensitive to _______________ and the other type is sensitive to ___________ or _________ stimuli

non-noxious mechanical stress; noxious mechanical or biomechanical stimuli

What is the primary distribution of free nerve endings?

all joints

Where are golgi ligament endings located?

ligaments, adjacent to ligament’s bony attachement

What are golgi ligament endings sensitive to?

tension or stretch on ligaments

What is the primary distribution of golgi ligament endings?

majority of joints

Where are golgi mazzoni corpuscles located?

joint capsule

What are golgi mazzoni corpuscles sensitive too?

compression of joint capsule

Where are the Golgi-Mazzoni corpuscles primarily distributed?

knee joint, joint capsule

Where are Pacinian corpuscles located?

fibrous layer of joint capsule

What are Pacinian corpuscles sensitive too?

high frequency vibration, acceleration, and high velocity changes in jk

Where are pacinian corpuscles primarily located?

all joints

Where are ruffini endings located?

fibrous layer of joint capsule

What are ruffini endings sensitive too?

stretching of joint capsule; amplitude and velocity of joint position

Where are ruffinin endings primarily distributed?

greater density in proximal joints, particularly in capsular regions

Type I Slow twitch muscle fibers are: aerobic or anerobic

aerobic

Type II Fast twitch muscle fibers are: aerobic or anerobic

anerobic

Type I slow twitch fibers are: red or white

red

Type II slow twitch fibers are: red or white

white

Type I slow twitch fibers are: phasic or tonic

tonic

Type II slow twitch fibers are: phasic or tonic

phasic

Type I slow twitch fibers are: slow, oxidative or fast-glycolytic

slow, oxidative

Type II slow twitch fibers: slow, oxidative or fast glycolytic

fast glycolytic

Where are muscle spindles distributed?

throughout the belly of the muscle

What is the function of the muscle spindles?

send information to the nervous system about muscle length and/or rate of change of its length