Chapter 5 - The Nervous, Muscular, and Skeletal Systems

Question 1

Human Movement System (HMS)

The collective components and structures that work together to move the body: are muscular, skeletal, and nervous systems.

Question 2

Kinetic Chain

A concept that describes the human body as a chain of interdependent links that work together to perform movement.

Question 3

Nervous System

A network of specialized cells called neurons that transmit and coordinate signals, providing a communication network within the human body.

Question 4

Neuron

A specialized cell that is the functional unit of the nervous system.

Question 5

Nucleus

Cellular structure or organelle that contains the majority of the cell’s genetic material in the form of chromosomes.

Question 6

Organelles

Tiny cellular structures that perform specific functions within the cell. Examples include nuclei, mitochondria, lysosomes, ribosomes, and the endoplasmic reticulum.

Question 7

Mitochondria

The parts of the cell that use nutrients to create energy for the cell; commonly known as the powerhouse of the cell.

Question 8

Effector Sites

A part of the body, such as a muscle or organ, that receives a signal from a neuron to produce a physiological response.

Question 9

Electrolytes

Minerals that have an electrical charge to help transmit nerve impulses throughout the body, such as sodium, potassium, and magnesium.

Question 10

Interneurons

Neurons located within the spinal cord and brain that transmit impulses between afferent and efferent neurons.

Question 11

Central Nervous System (CNS)

A division of the nervous system that includes the brain and spinal cord.

Question 12

Peripheral Nervous System (PNS)

Nerves that connect the rest of the body to the central nervous system.

Question 13

Afferent Pathway

Sensory pathway that relays information to the central nervous system.

Question 14

Efferent Pathway

A motor pathway that relays information from the central nervous system to the rest of the body.

Question 15

Mechanoreceptors

Specialized structures that respond to mechanical forces (touch and pressure) within tissues and then transmit signals through sensory nerves.

Question 16

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.

Question 17

Autonomic Nervous System

A division of the peripheral nervous system that supplies neural input to the organs that run the involuntary processes of the body (e.g. circulating blood, digesting food, producing hormones).

Question 18

Sympathetic Nervous System

Subdivision of the autonomic nervous system that works to increase neural activity and put the body in a heightened state.

Question 19

Parasympathetic Nervous System

Subdivision of the autonomic nervous system that works to decrease neural activity and put the body in a more relaxed state.

Question 20

Sensory Function

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

Question 21

Proprioception

The body’s ability to naturally sense its general orientation and relative position of its parts.

Question 22

Integrative Function

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

Question 23

Motor Function

The neuromuscular (or nervous and muscular systems) response to the integrated sensory information.

Question 24

Muscle Spindles

Sensory receptors sensitive to change in the length of the muscle and the rate of change.

Question 25

Stretch Reflex

Neurological signal from the muscle spindle that causes a muscle to contract to prevent excessive lengthening.

Question 26

Golgi Tendon Organ (GTO)

A specialized sensory receptor located at the point where skeletal muscle fibers insert into the tendons of skeletal muscle, sensitive to changes in muscular tension and rate of tension change.

Question 27

Joint Receptors

Receptors located in and around the joint capsule that responds to pressure, acceleration, and deceleration of the joint.

Question 28

Neuroplasticity

The concept that the brain will continually change or grow, reforming new neural pathways throughout an individual’s entire life span.

Question 29

Neurocircuitry

The interconnection of neurons in the brain and spinal cord.

Question 30

Motor Skills

Specific movements through the coordinated effort of the sensory and motor subsystems.

Question 31

Skeletal System

A description of the bones of the body.

Question 32

Osteoporosis

A condition of reduced bone mineral density, which increases risk of bone fracture.

Question 33

Joints

The sites where two bones meet and movement occurs as a result of muscle contraction.

Question 34

Axial Skeleton

A division of the skeletal system consisting of the skull, the rib cage, and the vertebral column.

Question 35

Appendicular Skeleton

A division of the skeletal system consisting of the arms, legs, and pelvic girdle.

Question 36

Levers

Rigid rods where muscles attach.

Question 37

Remodeling

The process by which bone is consistently renewed by the resorption and formation of the bone structure.

Question 38

Osteoclasts

Special cells that break done and remove old bone tissue.

Question 39

Osteoblasts

Special cells that form and lay down new bone tissue.

Question 40

Wolff’s Law

Scientific explanation of remodeling (new bone growth) occurs along the lines of stress placed on the bone.

Question 41

Depressions

Flattened or indented portions of bone.

Question 42

Processes

Projections protruding from the bone where tendons and ligaments can attach.

Question 43

Verterbral Column

Bones that house the spinal cord; consists of the cervical, thoracic, and lumbosacral regions.

Question 44

Spinal Cord

Bundle of nerves housed within the vertebrae.

Question 45

Intervertebral Discs

Fibrous cartilage structures between vertebrae that act as shock absorbers and assist with movemment.

Question 46

Neural Spine

Represents a position in which the vertebrae and associated structures are under the least amount of load and can most optimally support functional movement.

Question 47

Osteokinematics

Movement of a limb that is visible.

Question 48

Arthrokinematics

The description of joint surface movement; consists of three major types; roll, slide, and spin.

Question 49

Synovial Joints

A joint with a fluid-filled joint capsule.

Question 50

Nonaxial

A gliding joint that moves in only one plane, either back and forth or side to side.

Question 51

Nonsynovial Joints

Joints that have no joint capsule, fibrous connective tissue, or cartilage in the uniting structure.

Question 52

Ligament

A fibrous connective tissue that connects bone to bone.

Question 53

Collagen

A protein found in connective tissue, muscles, and skin that provides strength and structure. It is the most abundant protein in the human body.

Question 54

Elastin

A protein that provides elasticity to skin, tendons, ligaments, and other structures.

Question 55

Growth Plate

A specialized cartilage disc located in the epiphysis that is responsible for longitudinal bone growth.

Question 56

Skeletal Muscle

The type of muscle tissue that connects to bones and generates the forces that creat movement.

Question 57

Fascia

Connective tissue that surrounds muscles and bones.

Question 58

Epimysium

Inner layer of fascia that directly surrounds an entire muscle, commonly referred to as the “deep fascia”.

Question 59

Fascicles

Largest bundles of fibers within a muscle. Fascicles are surrounded by perimysium.

Question 60

Perimysium

Connective tissue surrounding a muscle fascicle.

Question 61

Endomysium

Connective tissue that wraps around individual muscle fibers within a fascicle.

Question 62

Glycogen

Glucose that is deposited and stored in bodily tissues, such as the liver and muscle cells; the storage form of carbohydrates.

Question 63

Myoglobin

Protein-based molecule that carries oxygen molecules into the muscles.

Question 64

Myofibrils

The contractile components of a muscle cell; the myofilaments (actin and myosin) are contained within a myofibril.

Question 65

Myofilaments

The filaments of a myofibril; include actin and myosin.

Question 66

Actin

The thin, stringlike, myofilament that acts along with myosin to produce muscular contraction.

Question 67

Myosin

The thick myofilament that acts along with actin to produce muscular contraction.

Question 68

Sarcomere

The structural unit of a myofibril composed of actin and myosin filaments between two Z-lines.

Question 69

Neural Activation

The nervous system’s signal that tells a muscle to contract.

Question 70

Z - Line

The meeting point of each sarcomere.

Question 71

Neuromuscular Junction

The specialized site where the nervous system communicates directly with muscle fibers.

Question 72

Synapse

A junction or small gap between the motor neuron and muscle cells.

Question 73

Motor Unit

A motor neuron and all of the muscle fibers that it innervates (stimulates).

Question 74

Action Potential

Nerve impulse that is relayed from the central nervous system, through the peripheral nervous system,
and into the muscle across the neuromuscular junction.

Question 75

Neurotransmitters

Chemical messengers that cross the synapse between neuron and muscle and assist with nerve
transmission.

Question 76

Acetylcholine (ACh)

A neurotransmitter that helps the action potential cross the synapse into the muscle, which initiates the steps in a muscle contraction.

Question 77

Sliding Filament Theory

The series of steps in muscle contraction involving how myosin (thick) and actin (thin) filaments
slide past one another to produce a muscle contraction, shortening the entire length of the sarcomere.

Question 78

Excitation-contraction coupling

The physiological process of converting an electrical stimulus to a muscle contraction.

Question 79

Power Stroke

The myosin heads bind to actin and pull them toward the sarcomere center, which slides the filaments past each other, shortening the muscle.

Question 80

Adenosine Triphosphate

A high-energy molecule that serves as the main form of energy in the human body;
known as the energy currency of the body.

Question 81

Resting Length

The length of a muscle when it is not actively contracting or being stretched.

Question 82

Type 1 (slow-twitch) muscle fibers

Muscle fibers that are small in size, generate lower amounts of force and are more resistant to fatigue.

Question 83

Type II Muscle Fibers

Muscle fibers that are larger in size, generate higher amounts of force and are faster to fatigue.

Question 84

All-or-nothing principle

Motor units cannot vary the amount of force they generate; they either contract maximally or not at all.

Question 85

Capillaries

The smallest blood vessels and the site of exchange of elements between the blood and the tissues.