Chapter 5 - The Nervous, Skeletal, and Muscular Systems Flashcards

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1
Q

What is the definition of the human movement system?

A

The combination and interrelation of the nervous, muscular, and skeletal systems. It includes functional anatomy, functional biomechanics, and motor behavior.

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2
Q

What are the three primary functions of the nervous system?

A
  1. Sensory Function
  2. Integrative Function
  3. Motor Function
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3
Q

What is the nervous system?

A

A conglomeration of billions of cells specifically designed to provide a communication network within the human body.

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4
Q

What is sensory function?

A

The ability of the nervous system to sense changes in either the internal or external environment.

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5
Q

Define integrative function.

A

The ability of the nervous system to analyze and interpret sensory information to allow for proper decision making, which produces the appropriate response.

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6
Q

What is motor function?

A

The neuromuscular response to the sensory information.

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7
Q

Define proprioception.

A

The cumulative sensory input to the central nervous system from all mechanoreceptors that sense body position and limb movement.

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8
Q

What is the cell body of a neuron / What does it contain?

A

The neuron cell body contains the nucleus and other organelles, including lysosomes, mitchondia, and a Golgi complex.

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9
Q

What is the primary function of dendrites in a neuron?

A

Dendrites gather information from other structures and transmit it back into the neuron.

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10
Q

What is the axon of a neuron?

A
  • A cylindrical projection from the cell body that transmits nervous impulses to other neurons or effector sites (muscles, organs).
    (Passes messages away from the cell body to the other neurons, muscles or glands.)
  • It is the part of the neuron that provides communication from the brain and spinal cord to other parts of the body.
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11
Q

What is a neuron?

A

A specialized cell that processes and transmits information through both electrical and chemical signals.

It is the functional unit of the nervous system and is divided into 3 main parts: the cell body, axon, and dendrites.

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12
Q

What are sensory (afferent) neurons?

A

Sensory neurons transmit nerve impulses from effector sites (such as muscles and organs) via receptors to the brain and spinal cord.

They respond to touch, sound, light, and other stimuli and transmit nerve impulses from effector sites.

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13
Q

What are interneurons?

A

Interneurons are neurons that transmit nerve impulses from one neutron to another.

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14
Q

What do motor (efferent) neurons do?

A

Motor neurons transmit nerve impulses from the brain and spinal cord to effector sites such as muscles or glands.

Example: brain tells hand muscles to let go of a hot coffee cup (after interpreted it was hot from sensory neurons and communicated through Interneurons).

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15
Q

What are the two main functions of peripheral nervous system and what is its main purpose?

A
  1. Providing a connection for the nervous system to activate different effector sites, such as muscles (motor function).
  2. Relaying information from effector sites back to the brain via sensory receptors (sensory function).

Overall peripheral nerves/nervous system provide a constant update on the relation between the body and the environment.

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16
Q

What is the peripheral nervous system (PNS)?

A

The PNS consists of 12 cranial nerves, 31 pairs of spinal nerves (which branch out from the brain and spinal cord), and sensory receptors that spread throughout the body.

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17
Q

What are the subdivisions of the PNS and what are their main functions?

A
  1. Somatic nervous system: nerves that serve the outer areas of the body and skeletal muscle, and are largely responsible for the voluntary control of movement.
  2. Autonomic nervous system: supplies neural input to the involuntary systems of the body (heart, digestive systems, and endocrine glands).
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18
Q

What are the subdivisions of the autonomic system and what are their functions?

A
  1. Sympathetic - increase levels of activation in preparation for activity
  2. Parasympathetic - decrease levels of activation during rest and recovery.
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19
Q

What are sensory receptors and what are the 4 subcategories they are divided into?

A

Sensory receptors are specialized structures located throughout the body that convert environmental stimuli (heat, light, sound, taste, and motion) into sensory information that the brain and spinal cord use to produce a response.

  1. mechanoreceptors (touch and pressure)
  2. nociceptors (pain receptors)
  3. chemoreceptors (chemical interaction / smell and taste)
  4. photo receptors (light / vision)
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20
Q

What are mechanoreceptors and where are they located?

A

Mechanoreceptors are sensory receptors responsible for sensing distortion in body tissues / respond to mechanical pressure and outside forces (touch, pressure, stretching, sound waves, and motion) within tissues and then transmit signals through sensory nerves.

They are located in muscles, tendons, ligaments, joint capsules, and include muscle spindles, Golgi tendon organs, and joint receptors.

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21
Q

What are muscle spindles and what do they help regulate?

A

Muscle spindles are receptors that run parallel to muscle fibers that are sensitive to change in length of the muscle and the rate of that change.

Muscle spindles help regulate the contraction of muscles via the stretch reflex mechanism (when stretching.

The spindle sends an impulse to the brain, the brain then sends info to contract muscle within 1 to 2 milliseconds to prevent overstretching and potential muscle damage.

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22
Q

What are Golgi tendon organs (GTOs), where are they located, and what is the reaction when they are activated?

A

GTOs are receptors sensitive to change in tension of the muscle and the rate of that change.

They are located where skeletal muscle fibers insert the tendons of skeletal muscle.

Activation of the Golgi tendon organ will cause the muscle to relax, which prevents the muscle from excessive stress or possibility of injury.

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23
Q

What are joint receptors, where are they located, what do they activate in order to prevent too much stress on a joint?

A
  • Receptors surrounding a joint that respond to pressure, acceleration, and deceleration of the joint, and act to signal extreme joint positions in order to prevent injury.
  • Located in and around the joint capsule.
  • Can initiate a reflexive inhibitory response in the surrounding muscles if there is too much stress placed on that joint.
  • Examples: Ruffini endings and Pacinian corpuscles
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24
Q

What is a kinetic chain and what is its primary purpose?

A

The kinetic chain is the linked system of nerves, muscles, and joints that work together to produce movements.

The kinetic chain integrates these systems to produce efficient movement.

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25
Q

Define kinetic.

A

To produce motion/force

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26
Q

What is the skeletal system and how many bones does it contain?

A
  • The body’s framework, composed of bones and joints. It provides the shape and form for our bodies in addition to supporting, protecting, allowing body movement, producing blood for the body, and storing minerals.
  • Composed of 206 bones (approx. 177 are used in voluntary movement)

Note: the growth, maturation, and functionality of the skeletal system are greatly affected by posture, physical activity, and nutrition status.

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27
Q

What is the central nervous system (CNS)?

A

The portion of the nervous system that consists of the brain and spinal cord.

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28
Q

What is the axial skeleton, and how many bones does it contain?

A

The portion of the skeletal system that consists of the skull, rib age, and vertebral column.

Contains approximately 80 bones.

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29
Q

Define joints.

A

Joints are the junctions of bones, muscles, and connective tissue at which movement occurs.

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30
Q

What is the appendicular skeleton, and how many bones does it contain?

A

The portion of the skeletal system that includes the upper and lower extremities as well as shoulders and pelvic girdles.

Contains approximately 126 bones.

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31
Q

What is special about the pelvic girdle in regard to axial or appendicular skeletons?

A

The pelvic girdle is often considered a component of either the axial or appendicular system and is actually a link between the two systems.

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32
Q

What are the two vital functions of bones?

A
  1. Act and perform as levers when acted on by muscles.
  2. Provide Support, which translates into posture and is necessary for the efficient distribution of forces acting on the body.
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33
Q

Define bones.

A

Bones are hard structures that provide a resting ground for muscles and protection of vital organs.

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34
Q

Define remodeling.

A

The process of resorption and formation of bone.

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35
Q

What are the 5 major types of bones?

A
  1. Long Bones
  2. Short Bones
  3. Flat Bones
  4. Irregular Bones
  5. Sesamoid Bones
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36
Q

Define osteoblasts.

A

A type of cell that is responsible for bone formation

Osteoblasts lay down new bone tissue to replace the old during remodeling.

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37
Q

Define osteoclasts.

A

A type of bone cell that removes bone tissue during resorption.

Osteoclasts break down during resorption, removed by osteoclasts.

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38
Q

Define long bones.

A
  • Bones with a long, cylindrical body (shaft), with irregular or widened bony ends with slight curvature that is necessary for efficient force distribution.
  • Composed predominately of compact bone tissue to ensure strength and stiffness.
  • Contains considerable amounts of spongy bone tissue for shock absorption.
  • Upper Body Long Bones: clavicle, humerus, radius, ulna, metacarpals, and phalanges.
  • Lower Body Long Bones: femur, tibia, fibula, metatarsals, and phalanges.
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39
Q

What is epiphysis?

A
  • The end of long bones, which is mainly composed of cancellous bone, and houses much of the red marrow involved in red blood cell production.
  • They are also one of the primary sites for bone growth.

Note: during growth periods, the area can be vulnerable to injury.

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40
Q

What is diaphysis?

A

The shaft portion of the long bone, predominately consisting of compact bone with a hollow inside shaft.

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41
Q

What is epiphyseal plate?

A
  • The region of long bone connecting the diaphysis to the epiphysis.
  • It is a layer of subdividing cartilaginous cells in which growth in length of the diaphysis occurs.

Note: damage to the epiphyseal plate before the end of growth in puberty could result in shorter bone

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42
Q

What is a periosteum?

A
  • A dense, tough membrane composed of fibrous connective tissue that closely wraps (invests) all bone, except that of the articulating surfaces in joints, which are covered by a synovial membrane.
  • It contains nerves, blood vessels, and bone-producing cells
  • Inner surface provides the materials for nutrition repair and facilitates growth in the diameter of the bone.
  • Fundamental Role in movement by providing the point of attachment for tendons.
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43
Q

Define medullar cavity.

A

The space that runs down through the center of the diaphysis and contains fatty yellow marrow that is predominately composed of adipose tissue and serves as a useful energy reserve.

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44
Q

What is articulate (hyaline) cartilage?

A
  • Cartilage that covers the articular surfaces of bones.
  • Hard, white, shiny tissue that, along with synovial fluid, helps reduce friction in freely moveable (synovial joints).
  • Fundamental for smooth joint action.
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45
Q

What are short bones? Give examples.

A
  • Similar in length and width and appear somewhat cubical in shape.
  • Consist predominately of spongy bone tissue to maximize shock absorption.
  • Examples: carpals of hands and tarsals of feet
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46
Q

What are flat bones? Give examples.

A
  • Thin bones comprising two layers of compact bone tissues surrounding a layer of spongy bone tissue.
  • Involved in protection of internal structures.
  • Provide broad attachments for muscles.
  • Examples: sternum, scapulae, ribs, ilium, and cranial bones.
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47
Q

What are irregular bones? Give examples.

A
  • Unique shape and function
  • Do not fit characteristics of other bone categories.
  • Examples: vertebrae, pelvic bones, and certain facial bones.
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48
Q

What are sesamoid bones? Give an example.

A
  • Small bones embedded in a joint capsule or found in locations where a tendon passes over a joint.
  • Develop within particular tendons at a site of considerable friction or tension.
  • Serve to improve leverage and protect the joints from damage.
  • Example: the patella in the knee
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49
Q

What are “processes” (in reference to bones)? What are the 5 common processes of bones?

A
  • Projections protruding from the bone where muscles, tendons, and ligaments can attach.
  • More common processes:
    • Process
    • Condyle
    • Epicondyle
    • Tubercle
    • Trochanter
50
Q

What are “processes” (in reference to bones)? What are the 6 common processes of bones?

A
  • Projections protruding from the bone where muscles, tendons, and ligaments can attach.
  • More common processes:
    1. Spinous
    2. Coracoid
    3. Condyle
    4. Epicondyle
    5. Tubercle
    6. Trochanter
51
Q

What are the 5 categories in which the vertebral column is divided, where are the located, and what are their corresponding functions/purposes?

A
  1. Cervical vertebrae (C1-C7): first 7 vertebrae starting at the top of the spinal column that form a flexible framework and provide support and motion for the head.
  2. Thoracic vertebrae (T1-T12): next 12 vertebrae located in the upper and middle back behind the ribs. Move with the ribs to form rear anchor to the rib cage. Larger than cervical vertebrae and increase in size from top to bottom.
  3. Lumbar vertebrae (L1-L5): 5 vertebrae of the low back below the thoracic spine. Support most of the body’s weight and are attached to many of the back muscles. Often a location of pain since these vertebrae carry the most amount of weight and are subject to the largest forces and stresses along the spine.
  4. Sacrum: triangular bone located below the lumbar spine. Consists of 4 or 5 sacral vertebrae in a child, which become fused into a single bone during adulthood.
  5. Coccyx: located below the sacrum, more commonly known as the tailbone. Consists of 3 to 5 bones that are fused together in an adult. Many muscles connect to the coccyx.
52
Q

What does neutral spine mean and what are the three types of curvatures?

A
  • Optimal arrangement of curves in which the vertebrae and associated structures are under the least amount of load.
    1. Posterior cervical curvature: a posterior concavity of the cervical spine.
    2. Anterior thoracic curvature: a posterior convexity of the thoracic spine.
    3. Posterior lumbar curvature: a posterior concavity of the lumbar spine.
53
Q

How are joints formed?

A

By two bones that articulate with one another.

54
Q

What is arthrokinematics and what are the three major motion types?

A

Joint motion

  1. Roll
  2. Slide
  3. Spin
55
Q

What is a joint rolling movement? Give an example.

A

One joint rolls across the surface of another like a bike tire rolls on the street.

Body example: femoral condyles moving (rolling) over the tibial condyles in a squat.

56
Q

What is a joint sliding movement? Give an example.

A

One joint’s surface slides across another like bike tires skidding on the street.

Body example: the tibial condyles moving (sliding) across the femoral condyles during a knee extension.

57
Q

What is a joint spinning movement? Give an example.

A

One joint’s surface rotates on another like twisting a lid of a jar.

Example: the head of the radius (a bone of the forearm) rotating on the end of the humerus during pronation and supination of the forearm.

58
Q

Synovial joints

A

Joints that are held together by a joint capsule and ligaments and are most associated with movement in the body.
These are the most common joint types - 80% of all joints in the body are synovial.

59
Q

What is the purpose of the synovial joint design? What are the 3 parts of the synovial joint?

A

To increase mobility.

  1. Synovial capsule: collagenous structure surrounding the entire joint
  2. Synovial membrane: inner layer of the capsule
  3. Hyaline cartilage: pads the ends of the articulating bones
60
Q

What is synovial fluid? What is its purpose? Where is it produced?

A

A fluid that resembles egg whites and works like engine oil.
It is secreted within joint capsule from synovial membrane to lubricate joint surfaces to reduce excessive wear and to nourish the cartilage cells that line the joint.

61
Q

How many types of synovial joints are there? List them.

A

6 types.

  1. Gliding (plane)
  2. Condyloid (condylar or ellipsoidal)
  3. Hinge
  4. Saddle
  5. Pivot
  6. Ball-and-socket
62
Q

Explain a gliding (plane) joint’s purpose and movement. Give examples.

A
  • A nonaxial joint that has the simplest movement of all joints.
  • Movement: Either back and forth or side to side.
  • Examples:
    1. Foot joint between the navicular bone and the second and third cuneiform bones
    2. The carpals of the hand
    3. The facet (spine) joints
63
Q

Explain a condyloid (condylar or ellipsoidal) joint’s purpose and movement. Give examples.

A
  • Named because the condyle of one bone fits into the elliptical cavity of another bone to form a joint.
  • Movement: predominately occurs in one plane (flexion and extension in the sagittal plane) with minimal movement in others (rotation in the transverse plane, adduction, and abduction in the frontal plane).

Examples:

  1. Wrist between the radius and the carpals
  2. The joints of the fingers (metacarpophalangeal).
64
Q

Explain a hinge joint’s purpose and movement. Give examples.

A
  • A uniaxial joint allowing movement predominately in only one plane of motion, the sagittal plane.
  • Examples:
    1. Elbow
    2. Interphalangeal (toes)
    3. Ankle
65
Q

Explain a sliding joint’s movement, where it’s located and how it got it’s name. Give examples of movement planes.

A
  • One bone looks like a saddle, the other articulating bone straddles it like a rider.
  • Only found in the carpometacarpal joint in the thumb.
  • Movement: predominantly in two planes of motion (flexion and extension in the sagittal plane, adduction and abduction in the frontal plane) with some rotation to produce circumduction (circular motion).
66
Q

Explain a pivot joint’s movement and location. Give examples of movement plane.

A
  • Allow movement in one plane of motion (rotation, pronation, and supination in the transverse plane.
  • Location:
    1. in the atlantoaxial joint at the base of the skull (top of the spine)
    2. In the proximal radioulnar joint at the elbow.
67
Q

Explain why ball-and-socket joints are the most mobile of the joints. Give an example.

A
  • They allow movement on all three planes.

- Examples: shoulder and hip

68
Q

What are nonsynovial joints? Explain their movement and give examples.

A

Joints that do not have a joint cavity, connective tissue, or cartilage.
They exhibit little to no movement.
*Examples: sutures of the skull, the distal joint of the tibia and fibula, and the symphysis pubis (pubic bones).

69
Q

Why do ligaments not repair or heal very well and may be slower to adapt to the stress placed on the body?

A

Ligaments have poor vascularity (or blood supply) and thus are slower to heal.

70
Q

What are depressions?

A

-Flattened or indented portions of bone, which can be muscle attachment sites.

A common depression is known as a “fossa”

Example: the supraspinous or infraspinous fossa located on the scapulae (shoulder blades).

Another form of depression: “sulcus”

Example: intertubercular sulcus located between the greater and lesser tubercles of the humerus (upper arm bone).

71
Q

What is the muscular system?

A

Series of muscles that moves the skeleton.

72
Q

Define what “muscle” literally means. What are the 3 main types of muscles in the body?

A
  • Multiple bundles of muscle fibers held together by connective tissue.

Three types:

  1. Skeletal
  2. Cardiac
  3. Smooth
73
Q

Explain the function of the ligament, what it is made of, and give an example.

A

Function:
- Primary connective tissue that connects bones together to provide static and dynamic stability, as well as input to the nervous system (proprioception), guidance, and the limitation of improper joint movement.

Made of:

  • Primarily collagen (a protein that runs parallel to the forces that are typically placed on a ligament)
  • Contain varying amounts of elastin (a second protein that provides flexibility or elastic recoil to withstand bending and twisting)
  • Not all ligaments will have the same amount of elastin.

Example:
- Anterior cruciate ligament (ACL) of the knee contains very little elastin and is mostly collagen and is much better suited for resisting strong forces and making a good stabilizing structure of the knee.

74
Q

What is epimysium? Where does it connect?

A
  • The first bundle (actual muscle itself) wrapped by an outer layer of connective tissue (fascia), and an inner layer that is underneath the fascia and surrounds the muscle (epimysium).
  • Fascia and epimysium are also connected to the bone and help to form the muscle’s tendon.
75
Q

Define fascia.

A
  • The outermost layer of connective tissue that surrounds the muscle.
76
Q

Define fascicle.

A
  • A grouping of muscle fibers that house the myofibrils.
77
Q

What is perimysium?

A
  • The connective tissue that surrounds the fascicles.
78
Q

What are myofibrils and where are they located?

A

A portion of the muscle that contains myofilaments located in the cell components of the sarcolemma.

79
Q

What are myofilaments?

A

The contractile components of muscle tissue known as actin (thin stringlike filaments) and myosin (thick filaments) that form a number of repeating sections within the myofibril. Each section is known as a sarcomere.

80
Q

What is the sarcolemma?

A
  • A plasma membrane that encase muscle fibers that contain cell components such as cellular plasma (sarcoplasm)
81
Q

What is sarcoplasm?

A
  • Cell components, or cellular plasma, that contains glycogen, fats, minerals, and oxygen-binding myoglobin that are contained within the sarcolemma.
82
Q

What is tropomyosin and where is it located?

A
  • Location: on the actin filament
  • Function: block myosin binding sites located on the actin filament, keeping myosin from attaching to actin when the muscle is in a relaxed state.
83
Q

What is troponin and where is it located?

A
  • Location: on actin filament
  • Function: plays a role in muscle contraction by providing binding sites for both calcium and tropomyosin when a muscle needs to contract.
84
Q

Define tendons.

A
  • Connective tissues that attach muscle to bone and provide an anchor for muscles to produce/exert force and control the bone and joint.
  • Similar to ligaments: poor vascularity (blood supply)
85
Q

What is the neuromuscular junction?

A

-A specialized synapse (junction/point) at which the (motor) neuron meets and communicates the muscle (fibers) to allow the action potential to continue its impulse.

86
Q

What is neural activation?

A
  • The contraction of a muscle generated by neural stimulation.
87
Q

What is endomysium?

A
  • The deepest layer of connective tissue that surrounds individual muscle fibers.
88
Q

What is a sarcomere?

A
  • The functional unit of the muscle (much like the neuron is for the nervous system) that produces muscular contraction and consists of repeating sections of actin and myosin.
89
Q

Define a motor unit.

A
  • A motor neuron and all of the muscle fibers it innervates(connects).
90
Q

Explain the process of neurotransmitters and what the specific neurotransmitter used by the neuromuscular system is called.

A
  1. Once released, they link with receptor sites on the muscle fiber specifically designed for their attachment.
  2. Once attached, ACh (acetylcholine -neurotransmitter used by neuromuscular system) stimulates the muscle fibers to go through a series of steps that initiates muscle contractions.
91
Q

What are neurotransmitters?

A
  • Chemical messengers that cross the neuromuscular joint junction (synapse) to transmit electrical impulses from the nerve to the muscle.
92
Q

What is the sliding filament theory? List/describe the steps.

A
  • The proposed process by which the contraction of the filaments within the sarcomere take place.
  • Describes how thick and thin filaments within the sarcomere slide past one another, shortening the entire length of the Sacromere and thus shortening the muscle and producing force.
    1. A sarcomere shortens as a result of the Z lines moving closer together.
    2. The Z lines converge as a result of myosin heads attaching to the actin filament and asynchronously pulling (power strokes) the actin filament across the myosin, resulting in shortening of the muscle fiber.
93
Q

What are “Z” lines?

A

Z lines denote the dividing line between each sarcomere.

During muscle contraction, the Z lines move towards one another due to the overall shrinking of each sarcomere.

94
Q

Describe excitation-contraction Coupling

A
  • The process of neural stimulation creating a muscle contraction.
  • It involves a series of steps that start with the initiation of a neural message (neural activation) and end up with a muscle contraction (sliding filament theory).
95
Q

Explain the “all or nothing” law of motor units.

A
  • Bottom line: Motor units cannot vary the amount of force they generate; they either contract maximally or not at all.
  • Examples:
    1. If the stimulus is strong enough to trigger an action potential, then it will spread through the whole length of the muscle fiber. It will spread through all muscle fibers supplied by a single nerve.
    2. If the stimulus is not strong enough, then there will be no action potential and no muscle contraction.
96
Q

What is another way to say “electrical impulses?”

A
  • Action potentials.
97
Q

Describe Type I Muscle Fibers

A
  • Slow twitch
  • Large number of capillaries, mitochondria (which transforms energy from food into ATP, or cellular energy), and myoglobin, which allows for improved delivery of oxygen.
  • Smaller in size
  • Slow to fatigue
  • Long-term contractions (stabilization)
    Example:
  • Sitting upright while maintaining ideal posture against gravity, for an extended period of time.
    -Referred to as “red fibers” as it is similar to hemoglobin (red pigment found in red blood cells)
98
Q

Describe Type II muscle fibers

A
  • Fast-twitch
  • Separated into 2 subdivisions based off vehemently and mechanical properties (Type IIa and Type IIx)
  • Fewer capillaries, mitochondria, and myoglobin
  • Known as “white fibers”
    1. Type IIa - higher oxidative capacity and fatigued more slowly than Type IIx - known as intermediate fast-twitch fibers because can use both aerobic and anaerobic metabolism almost equally to create energy making them a combo of Type I and Type II.
    2. Type IIx- low oxidative capacity (ability to use oxygen) and fatigue quickly.

Example: movements requiring force and power such as a sprint.

99
Q

Describe the 4 types of muscle functions and give an example.

A
  1. Agonist: ‘prime mover’ - muscles most responsible for a particular movement. Ex. gluteus maximus is an agonist for hip extension.
  2. Synergist: assist prime mover - Ex. the hamstring complex and the erector spinae are synergist with the gluteus maximus during hip extension.
  3. Stabilizer: Stabilize body while prime mover and Synergist Work - Ex. tansversus abdominis, internal oblique, and multifidus (deep muscles in lower back) stabilize low back, pelvis, and hips (lumbo-pelvic-hip complex) during hip extension.
  4. Antagonist: oppose prime mover - Ex. the psoas (a deep hip flexor) is antagonistic to the gluteus maximus during hip extension.
100
Q

Describe the endocrine system and what it consists of.

A
  • Literal meaning: “hormone secreting”
  • The system of glands that secrete hormones into the bloodstream to regulate the control of mood, growth and development, tissue function, and metabolism.

Consists of:

  • Host organs (glands)
  • Chemical messengers (hormones)
  • Target (receptor) cells.

Special proteins will bind to some hormones, acting as carriers that control the amount of hormone that is available to interact with and affect the target cells.

101
Q

Describe the hormones secreted from the anterior lobe of the pituitary gland.

A

Anterior lobe secretes:

  1. Growth hormone, prolactin to stimulate milk production after giving birth
  2. Adrenocorticorophic hormone (ACTH) to stimulate adrenal glands
  3. Thyroid-stimulating hormone (TSH) to stimulate thyroid gland
  4. Follicle-stimulating hormone (FSH) to stimulate ovaries and testes
  5. Luteinizing hormone (LH) to stimulate the ovaries or testes.
102
Q

What are the 4 primary endocrine glands?

A
  1. Hypothalamus
  2. Pituitary (“master” gland because it controls the functions of the other endocrine glands)
  3. Thyroid
  4. Adrenal glands.
103
Q

Describe the hormone secreted from the intermediate lobe of the pituitary gland.

A

Secretes melanocyte-stimulating hormone to control skin pigmentation

104
Q

Describe the hormone secreted from the posterior lobe of the pituitary gland.

A

Posterior lobe secretes:

  1. Antidiuretic hormone (ADH) to increase absorption of water into the blood by the kidneys
  2. Oxytocin to contract the uterus during childbirth and stimulate milk production
105
Q

What hormones does the thyroid gland affect and regulate.

A

Thyroid gland produces hormones that regulate the rate of metabolism and affect the growth and rate of function of many other systems in the body.

106
Q

What hormones do the adrenal glands secrete and in response to what?

A

Adrenal glands secrete hormones such as corticosteroids and catecholamines, including cortisol and adrenaline (epinephrine) in response to stress.

107
Q

What is the primary energy source used during vigorous exercise? What is it regulated by?

A

Carbohydrate, specifically glucose (also principal fuel for the brain) regulated by the pancreas which produces two specific hormones: insulin and glucagon.

108
Q

Decribe types of human function that the endocrine system’s hormones affect.

A
  • Triggering muscle contraction
  • Stimulating protein and fat synthesis
  • Activating enzyme systems
  • Regulating growth and metabolism
  • Determine how the body will physically and emotionally respond to stress.
109
Q

What are the two catecholamines (hormones produced in the adrenal glands) used during “fight or flight” response (aka. stress)?
What are the physiological effects that occur during this response that help sustain exercise activitiy?

A
  1. Epinephrine (adrenaline)
  2. Norepinephrine
    - Increases heart rate and stroke volume
    - Elevates blood glucose levels
    - Redistributes blood to working tissues
    - Opens up the airways
110
Q

What is glycogen?

A

The complex carbohydrate molecule used to store carbohydrates in the liver and muscle cells. When carbohydrate energy is needed, glycogen is converted into glucose for use by the muscle cells.

111
Q

What is the primary use of testosterone in both men and women in regards to exercise.

A
  • Fundamental role in growth and tissue repair.

- Raised levels of testosterone are indicative of an anabolic (tissue building) training status.

112
Q

What is the purpose of cortisol?

A

Under times of stress, such as exercise, cortisol is secreted by the adrenal glands and serves to maintain energy supply through the breakdown of carbohydrates, fats, and proteins.

113
Q

What is insulin?

A

A protein hormone released by the pancreas that helps glucose move out of the blood and into the cells in the body, where the glucose can be used as energy and nourishment.

114
Q

Where is the trochanter process located? The greater trochanter is commonly called _______.

A
  • Located at the top of the femur and are the attachment sites for the hip musculature.
  • The greater trochanter is commonly called the hipbone.
115
Q

Describe thyroid gland’s primary role and what it is regulated by.

A
  • Responsible for human metabolism (carbohydrate, protein, and fat metabolism), basal metabolic rate, protein synthesis, sensitivity to epinephrine, heart rate, breathing rate, and body temperature.
  • Regulated by pituitary gland
  • Low thyroid leads to: low metabolism, fatigue, depression, sensitivity to cold, and weight gain.
116
Q

Where is the Tubercle process located? There are greater and lesser tubercles, which are attachment sites for ______ musculature.

A
  • Located at the top of the humerus at the glenohumeral (shoulder) joint.
  • Shoulder musculature.
117
Q

Where is the epicondyle process located?

A
  • Located on the inner and outer portions of the humerus to help form the elbow joint.
118
Q

Where is the condyle process located?

A
  • Located on the inner and out portions at the bottom of the femur (thigh bone) and top of the tibia (shin bone) to form the knee joint.
119
Q

Where are the spinous process located? Where is the coracoid process located?

A
  • Spinous process found on the vertebrae and the acromion

- Coracoid processes found on the scapulae.

120
Q

What is growth hormone/What it is responsible for? What type of hormone is it primarily? What can it be stimulated by?

A
  • Responsible for most of the growth and development during childhood up to puberty, when primary sex hormones take over that control.
  • Increase development of bone, muscle tissue, and protein synthesis; increases fat burning; and strengthens the immune system.
  • Primarily an anabolic hormone
  • Stimulate by several factors (estrogen, testosterone, deep sleep, and vigorous exercise).