Chapter 5 - The Nervous, Skeletal, and Muscular Systems Flashcards
The combination and interrelation of the nervous, muscular, and skeletal systems. It includes functional anatomy, functional biomechanics, and motor behavior.
human movement system
What are the three primary functions of the nervous system?
- Sensory Function
- Integrative Function
- Motor Function
A conglomeration of billions of cells specifically designed to provide a communication network within the human body.
nervous system
The ability of the nervous system to sense changes in either the internal or external environment.
sensory function
The ability of the nervous system to analyze and interpret sensory information to allow for proper decision making, which produces the appropriate response.
integrative function
The neuromuscular response to the sensory information.
motor function
The cumulative sensory input to the central nervous system from all mechanoreceptors that sense body position and limb movement.
proprioception
Consists of a cell body containing the nucleus and other organelles, including lysosomes, mitchondia, and a Golgi complex.
neuron
Gather information from other structures and transmit it back into the neuron.
Dendrites
- 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.
axon
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.
neuron
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
Sensory neurons
Neurons that transmit nerve impulses from one neuron to another.
Interneurons
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).
Motor neurons
- Provides a connection for the nervous system to activate different effector sites, such as muscles (motor function).
- Relays information from effector sites back to the brain via sensory receptors (sensory function).
Provides a constant update on the relation between the body and the environment.
Peripheral nervous system
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.
peripheral nervous system
What are the subdivisions of the PNS and what are their main functions?
- Somatic nervous system: nerves that serve the outer areas of the body and skeletal muscle responsible for the voluntary control of movement.
- Autonomic nervous system: supplies neural input to the involuntary systems of the body (heart, digestive systems, and endocrine glands).
What are the subdivisions of the autonomic system and what are their functions?
- Sympathetic - increase levels of activation in preparation for activity
- Parasympathetic - decrease levels of activation during rest and recovery.
What are sensory receptors and what are the 4 subcategories they are divided into?
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.
- mechanoreceptors (touch and pressure)
- nociceptors (pain receptors)
- chemoreceptors (smell and taste)
- photo receptors (vision)
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.
mechanoreceptors
Receptors that run parallel to muscle fibers that are sensitive to change in length of the muscle
Help regulate the contraction of muscles via the stretch reflex mechanism when stretching.
Prevent overstretching and potential muscle damage.
Muscle spindles
Receptors sensitive to change in tension of the muscle
They are located where skeletal muscle fibers insert the tendons of skeletal muscle.
Activation will cause the muscle to relax, which prevents the muscle from excessive stress or possibility of injury.
Golgi tendon organs
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.
joint receptors
The linked system of nerves, muscles, and joints that work together to produce movements.
kinetic chain
Relating to motion and the forces and energy associated
kinetic
- Supports body
- Protects organs
- Allows body movement
- Produces blood for the body
- Stores minerals
Composed of 206 bones (approx. 177 are used in voluntary movement)
Note: the growth, maturation, and functionality of this system are greatly affected by posture, physical activity, and nutrition status.
skeletal system
The portion of the nervous system that consists of the brain and spinal cord.
central nervous system
The portion of the skeletal system that consists of the skull, rib cage, and vertebral column.
Contains approximately 80 bones.
axial skeleton
The junctions of bones, muscles, and connective tissue at which movement occurs.
Joints
The portion of the skeletal system that includes the upper and lower extremities as well as shoulders and pelvic girdles.
Contains approximately 126 bones.
appendicular skeleton
Often considered a component of either the axial or appendicular system and is actually a link between the two systems.
Pelvic girdle
- Act and perform as levers when acted on by muscles
- Provide Support, which translates into posture and is necessary for the efficient distribution of forces acting on the body
- Hard structures that provide a resting ground for muscles and protection of vital organs
Bones
The process of resorption and formation of bone
remodeling
What are the 5 major types of bones?
- Long Bones
- Short Bones
- Flat Bones
- Irregular Bones
- Sesamoid Bones
A type of cell that is responsible for bone formation
Osteoblasts
A type of bone cell that removes bone tissue during resorption
Osteoclasts
- 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.
long bones
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.
epiphysis
The shaft portion of the long bone, predominately consisting of compact bone with a hollow inside shaft.
diaphysis
- 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.
epiphyseal plate
- 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.
periosteum
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.
medullar cavity
- 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.
articulate (hyaline) cartilage
- 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
short bones
- 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.
flat bones
- Unique shape and function
- Do not fit characteristics of other bone categories.
- Examples: vertebrae, pelvic bones, and certain facial bones.
irregular bones
- 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
sesamoid bones
Projections protruding from the bone where muscles, tendons, and ligaments can attach.
Process
What are the 6 common processes of bones?
Spinous Coracoid Condyle Epicondyle Tubercle Trochanter
What are the 5 categories in which the vertebral column is divided, where are they located, and what are their corresponding functions/purposes?
- 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.
- 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.
- 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.
- 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.
- 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.
What does neutral spine mean and what are the three types of curvatures?
- 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.
How are joints formed?
By two bones that articulate with one another.
Elbow joint are: Humerus. Radius
Arthrokinematics
Joint motion
- Roll
- Slide
- Spin
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.
joint rolling movement
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.
joint sliding movement
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.
joint spinning movement
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
Synovial joints
What is the purpose of the synovial joint design? What are the 3 parts of the synovial joint?
To increase mobility.
- Synovial capsule: collagenous structure surrounding the entire joint
- Synovial membrane: inner layer of the capsule
- Hyaline cartilage: pads the ends of the articulating bones
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.
synovial fluid
How many types of synovial joints are there? List them.
6 types.
- Gliding (plane)
- Condyloid (condylar or ellipsoidal)
- Hinge
- Saddle
- Pivot
- Ball-and-socket
- 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
gliding (plane) joint
- 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:
- Wrist between the radius and the carpals
- The joints of the fingers (metacarpophalangeal).
condyloid (condylar or ellipsoidal) joint
- A uniaxial joint allowing movement predominately in only one plane of motion, the sagittal plane.
- Examples:
1. Elbow
2. Interphalangeal (toes)
3. Ankle
hinge joint
- 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).
saddle joint
- 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.
pivot joint
- The most mobile of the joints
- They allow movement on all three planes.
- Examples: shoulder and hip
ball-and-socket joints
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).
nonsynovial joints
Why do ligaments not repair or heal very well and may be slower to adapt to the stress placed on the body?
Ligaments have poor vascularity (or blood supply) and thus are slower to heal.
Flattened or indented portions of bone, which can be muscle attachment sites.
Example: the supraspinous or infraspinous “fossa” located on the scapulae (shoulder blades).
Depressions
Series of muscles that moves the skeleton.
muscular system
Multiple bundles of muscle fibers held together by connective tissue.
Three types
Muscle
- Skeletal
- Cardiac
- Smooth
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 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.
ligament
- The first bundle (actual muscle itself) wrapped by an outer layer of connective tissue (fascia), and an inner layer that is underneath the fascia
- Fascia and this bundle are also connected to the bone and help to form the muscle’s tendon.
epimysium
The outermost layer of connective tissue that surrounds the muscle.
fascia
A grouping of muscle fibers that house the myofibrils.
fascicle
The connective tissue that surrounds the fascicles.
perimysium
A portion of the muscle that contains myofilaments located in the cell components of the sarcolemma.
myofibrils
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.
myofilaments
A plasma membrane that encase muscle fibers that contain cell components such as cellular plasma (sarcoplasm)
sarcolemma
Cell components, or cellular plasma, that contains glycogen, fats, minerals, and oxygen-binding myoglobin that are contained within the sarcolemma.
sarcoplasm
Blocks myosin binding sites located on the actin filament, keeping myosin from attaching to actin when the muscle is in a relaxed state.
tropomyosin
Plays a role in muscle contraction by providing binding sites for both calcium and tropomyosin when a muscle needs to contract.
troponin
Connective tissues that attach muscle to bone and provide an anchor for muscles to produce/exert force and control the bone and joint.
tendons
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.
neuromuscular junction
The contraction of a muscle generated by neural stimulation.
neural activation
The deepest layer of connective tissue that surrounds individual muscle fibers.
endomysium
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.
sarcomere
A motor neuron and all of the muscle fibers it innervates(connects).
motor unit
Explain the process of neurotransmitters and what the specific neurotransmitter used by the neuromuscular system is called.
- Once released, they link with receptor sites on the muscle fiber specifically designed for their attachment.
- Once attached, ACh (acetylcholine -neurotransmitter used by neuromuscular system) stimulates the muscle fibers to go through a series of steps that initiates muscle contractions.
Chemical messengers that cross the neuromuscular joint junction (synapse) to transmit electrical impulses from the nerve to the muscle.
neurotransmitters
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 Sarcomere 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.
sliding filament theory
Denote the dividing line between each sarcomere.
During muscle contraction, these move towards one another due to the overall shrinking of each sarcomere.
Z lines
- 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).
excitation-contraction Coupling
Motor units cannot vary the amount of force they generate; they either contract maximally or not at all.
“all or nothing” law
Electrical impulses
Action potentials.
- 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)
Type I Muscle Fibers
- 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.
Type II muscle fibers
Describe the 4 types of muscle functions and give an example.
- Agonist: ‘prime mover’ - muscles most responsible for a particular movement. Ex. gluteus maximus is an agonist for hip extension.
- Synergist: assist prime mover - Ex. the hamstring complex and the erector spinae are synergist with the gluteus maximus during hip extension.
- Stabilizer: Stabilize body while Agonist and Synergist Work - Ex. transverses abdominis, internal oblique, and multifidus (deep muscles in lower back) stabilize low back, pelvis, and hips (lumbo-pelvic-hip complex) during hip extension.
- Antagonist: oppose prime mover - Ex. the psoas (a deep hip flexor) is antagonistic to the gluteus maximus during hip extension.
- 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.
endocrine system
Describe the hormones secreted from the anterior lobe of the pituitary gland.
Anterior lobe secretes:
- Growth hormone, prolactin to stimulate milk production after giving birth
- Adrenocorticorophic hormone (ACTH) to stimulate adrenal glands
- Thyroid-stimulating hormone (TSH) to stimulate thyroid gland
- Follicle-stimulating hormone (FSH) to stimulate ovaries and testes
- Luteinizing hormone (LH) to stimulate the ovaries or testes.
What are the 4 primary endocrine glands?
- Hypothalamus
- Pituitary (“master” gland because it controls the functions of the other endocrine glands)
- Thyroid
- Adrenal glands.
Describe the hormone secreted from the intermediate lobe of the pituitary gland.
Secretes melanocyte-stimulating hormone to control skin pigmentation
Describe the hormone secreted from the posterior lobe of the pituitary gland.
Posterior lobe secretes:
- Antidiuretic hormone (ADH) to increase absorption of water into the blood by the kidneys
- Oxytocin to contract the uterus during childbirth and stimulate milk production
Produces hormones that regulate the rate of metabolism and affect the growth and rate of function of many other systems in the body.
thyroid gland
Secrete hormones such as corticosteroids and catecholamines, including cortisol and adrenaline (epinephrine) in response to stress.
Adrenal glands
What is the primary energy source used during vigorous exercise? What is it regulated by?
Carbohydrate, specifically glucose (also principal fuel for the brain) regulated by the pancreas which produces two specific hormones: insulin and glucagon.
Describe types of human function that the endocrine system’s hormones affect.
- 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.
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 activity?
- Epinephrine (adrenaline)
- Norepinephrine
- Increases heart rate and stroke volume
- Elevates blood glucose levels
- Redistributes blood to working tissues
- Opens up the airways
The complex carbohydrate molecule used to store carbohydrates in the liver and muscle cells. When carbohydrate energy is needed, this is converted into glucose for use by the muscle cells.
glycogen
What is the primary use of testosterone in both men and women in regards to exercise.
- Growth and tissue repair.
- Raised levels of testosterone are indicative of an anabolic (tissue building) training status.
Under times of stress, such as exercise, this is secreted by the adrenal glands and serves to maintain energy supply through the breakdown of carbohydrates, fats, and proteins.
cortisol
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.
insulin
- Located at the top of the femur and are the attachment sites for the hip musculature.
- Commonly called the hipbone.
(greater) trochanter process
- 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.
thyroid gland
- Located at the top of the humerus at the glenohumeral (shoulder) joint.
- There are greater and lesser ones, which are attachment sites for shoulder musculature.
tubercle
Provides sites for the attachment of muscles
Located on the inner and outer portions of the humerus to help form the elbow joint.
epicondyle (rough)
Forms an articulation with another bone
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.
condyle (smooth)
Process found on the vertebrae and the acromion
Spinous process
- 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).
growth hormone
The cumulative sensory input to the central nervous system from all mechanoreceptors that sense body position and limb movement.
proprioception
Achieved by having an appropriate combination of:
- Proper alignment (posture) of the human movement system (kinetic chain)
- The stabilization strength necessary to maintain that alignment
Neuromuscular efficiency
