Chapter 3: Movement Systems Flashcards
Organ Systems
A group of organs working together to perform biological functions.
Nervous Tissue
Tissue found in the brain, spinal cord, and nerves that coordinates body activities.
Neurons
The most fundamental component of the brain and nervous system capable of transmitting information to and from other neurons, muscles, or glands.
Neuroglia
Cells in the brain and spinal cord that form a supporting structure for the neurons and provide them with insulation.
Neurosecretory Tissues
Neurons that translate neural signals into chemical stimuli.
Cell Body
The core and central structure of a neuron containing a nucleus and other specialized organelles that aid in nervous system function.
Axon
The thin tail-like structure of a neuron that generates and conducts nerve impulses.
Dendrites
Rootlike structures branching out from the cell body that receive and process signals from the axons of other neurons.
Sensory Neurons
Nerve cells involved in communicating tactile, auditory, or visual information.
Motor Neurons
Nerve cells that initiate muscle contraction or activate glands.
Interneurons
Nerve cells that connect neurons to other neurons.
Central Nervous System
The part of the nervous system consisting of the brain and spinal cord.
Peripheral Nervous System
The nerves and ganglia (relay areas for nerve signals) outside of the brain and spinal cord.
Cerebrum
The uppermost and largest part of the brain consisting of a left and right hemisphere; responsible for receiving and processing sensory information and controlling the body.
Cerebellum
The region of the brain responsible for conscious motor coordination.
Brain Stem
The trunk of the brain, consisting of the medulla oblongata, pons and midbrain that continues downward to form the spinal cord.
Cerebral Cortex
The part of the brain where most neural integration occurs.
Midbrain
The brain region responsible for motor movement and processing auditory and visual information.
Pons
The brain region responsible for posture, facial movement, and sleep.
Medulla Oblongata
The base of the brain stem, responsible for involuntary functions like swallowing, sneezing, and heart function.
Thalamus
The brain region responsible for relaying sensory and motor signals and regulating consciousness.
Decussation
The point of crossover of the nervous system in vertebrates located between the medulla oblongata and the spinal cord.
Frontal Lobe
The brain lobe involved in motor control, emotion, and language.
Motor Cortex
The region of the frontal lobe that plans and coordinates movement.
Prefrontal Cortex
The part of the frontal lobe responsible for high-level thinking and language.
Parietal Lobe
The brain lobe involved in processing sensory information.
Somatosensory Cortex
The region of the parietal lobe responsible for processing sensations like pain, temperature, and touch.
Temporal Lobe
The lateral lobe of the brain responsible for hearing, memory, and emotion.
Auditory Cortex
The region of the temporal lobe responsible for hearing.
Occipital Lobe
The posterior lobe of the brain responsible for vision.
Visual Cortex
The specific region of the occipital lobe responsible for sight and visual perception.
Hypothalamus
The region at the base of the brain responsible for maintaining homeostasis.
Homeostasis
A self-regulating process by which the body maintains the stability of its physiological processes for the purpose of optimal function.
Spinal Cord
The neural tissue extending from the medulla oblongata to the lumbar region (lower back) of the vertebral column.
Cranial Nerves
The 12 sensory and motor nerves extending directly from the brain.
Spinal Nerves
Bundles of nerves connected to the spinal cord carrying information toward the periphery.
Efferent Neurons
Motor neurons sending information from the CNS to the muscles to generate movement.
Afferent Neurons
Sensory neurons sending information from a stimulus to the CNS.
Somatic Nervous System
The part of the nervous system in charge of controlling voluntary movement.
Autonomic Nervous System
The part of the nervous system responsible for involuntary functions and movement.
Sympathetic Nervous System
The autonomic system responsible for “fight-or-flight.”
Parasympathetic Nervous System
The autonomic system responsible for “rest and digest.”
Internal Stimuli
Sensory input from within the body.
External Stimuli
Sensory input from external sources.
Mechanoreceptors
Nervous system receptors responding to mechanical stimuli such as sound or touch.
Proprioception
Perception or awareness of body movement or position.
Myelin Sheath
The insulation of neuron axons, made of proteins and fats, which propagates neural impulses.
Nerve Impulses
The electrical signals used for nerve communication.
Sensory Integration
The way the brain works to affect responses to neural input.
Motor Unit
A single motor neuron and the muscle fibers it controls.
Motor Unit Pool
A group of motor units that work together.
Mechanical Work
The amount of energy transferred by a force, the product of force and distance.
Extrafusal Muscle Fibers
The standard skeletal muscle fibers involved in creating mechanical work.
Alpha Motor Neurons
Motor neurons originating in the brain stem and spinal cord that initiate muscle contraction.
Excitation-Contraction Coupling
The physiological process of converting a neural impulse into a mechanical response.
Action Potential
An explosion of electrical activity caused by a neural impulse.
All-or-None Principle
The principle stating the strength of a neural electrical signal is independent of the magnitude of the stimulus so long as the neural threshold is achieved.
Cardiac Muscle
Striated involuntary muscle tissue found in the heart.
Smooth Muscle
Muscle tissue in the gut and internal organs that is involuntarily controlled.
Skeletal Muscle
The voluntary muscles attached to bones via tendons (thick fibrous connective tissue) that produces human movement.
Activities of Daily Living
The tasks usually performed in the course of a normal day in a person’s life, such as eating, toileting, dressing, bathing, or brushing the teeth.
Connective Tissue
Tissue that supports, connects, or binds other tissues or organs.
Sarcoplasm
The cytoplasm of a muscle fiber.
Glycogen
The stored form of glucose found in the liver and muscles.
Myofibrils
Parallel filaments that form muscle.
Myofilaments
The filaments of myofibrils composed of actin and myosin.
Actin
The thin filaments of muscle myofilaments where myosin bind to contract muscles.
Myosin
The thick filaments of myofilaments with a fibrous head, neck, and tail that bind to actin.
Sarcomere
The contractile unit of muscle tissue.
Z Line
The lateral boundary of the sarcomere where the myofilament actin attaches.
Endomysium
The connective tissue covering each muscle fiber.
Epimysium
Fibrous elastic tissue that surrounds a muscle.
Fasciculi
Bundles of muscle fibers; the singular is “fascicle.”
Perimysium
The connective tissue that covers a bundle of muscle fibers.
Tendon
A strong, fibrous cord made of collagen that attaches muscle to bone.
Periosteum
A dense layer of vascular connective tissue enveloping the bones except at the surfaces of the joints.
Neuromuscular Junction
The space between a motor neuron and muscle fiber.
Neurotransmitter
A chemical messenger that transmits messages between neurons or from neurons to muscles.
Acetylcholine
The neurotransmitter released by an action potential at the neuromuscular junction.
Sliding-Filament Theory
The interaction of actin and myosin that describes the process of muscle contraction.
Type I Fibers
Slow-twitch, fatigue-resistant muscle fibers with high mitochondrial density.
Mitochondria
An organelle with a double membrane and many folds inside responsible for generating the chemical energy needed for biochemical reactions.
Type IIA Fibers
Fast-twitch, moderately fatigable muscle fibers with moderate mitochondrial density.
Type IIX Fibers
Fast-twitch, fast-fatigable muscle fibers with low mitochondrial density.
Size Principle of Fiber Recruitment
Principle stating that motor units are recruited in order according to their recruitment thresholds and firing rates.
Fusiform Muscle
Spindle-shaped muscle.
Convergent Muscle
Muscle fibers converging from a broad origin (fixed point where the muscle attaches closest to the torso) to a single tendon of insertion (fixed point where the muscle attaches furthest from the torso).
Circular Muscle
Muscle fibers surrounding an opening in the body.
Parallel Muscle
Muscle fibers running parallel to the axis of the muscle.
Pennate Muscles
Muscles with fascicles that attach obliquely (diagonally).
Penniform
Muscle fibers that run diagonally in respect to the tendon similar to a feather.
Unipennate Muscle
Unipennate muscle: muscle fibers extending from one side of a central tendon.
Bipennate Muscle
Muscle fibers extending from both sides of a central tendon.
Multipennate Muscle
Muscle fibers extending from both sides of multiple central tendons.
Muscle Actions
Force production by a muscle that can result in a change of length (i.e., shortening or lengthening) or no length change at all.
Concentric Muscle Action
When the length of a muscle shortens as tension is produced.
Eccentric Muscle Action
When the length of a muscle increases as tension is produced.
Isometric Muscle Action
When the length of a muscle remains constant as tension is produced.
Stretch-Shortening Cycle
The cycling between the eccentric (stretch) action of a muscle and the concentric (shortening) action of the same muscle.
Joint
An articulation between two bones in the body.
Axial Skeleton
The bones of the head, trunk, and vertebrae.
Appendicular Skeleton
The bones of the shoulder girdle, pelvic girdle, and limbs.
Flat bones
These protect the internal organs and provide a large surface area for muscles to attach.
Short bones
Cube-shaped and provide stability and a limited amount of movement.
Long bones
Support body weight and facilitate movement.
Sesamoid bones
Small and round. Found in the joints and within tendons, they reinforce and protect tendons from stress and wear and tear.
Irregular bones
Serve a variety of purposes, including protecting vital organs.
Bone Marrow
The soft, spongelike tissue in the center of most bones containing stem cells of red or white blood cells or platelets.
Cancellous Bone
The meshwork of spongy tissue (trabeculae) of mature adult bone, typically found at the core of vertebral bones and the ends of the long bones.
Compact Bone
A denser material, also known as cortical bone, making up the hard structure of the skeleton.
Osteogenesis
The process of bone formation or remodeling.
Myositis Ossificans
A condition when bone tissue forms within a muscle or other soft tissue as a result of trauma or injury.
Wolff’s Law
The explanation for bone adaptations as a result of the loads placed on them.
Fibrous Joints
Joints with fibrous connective tissue joining two bones that allow for very little movement.
Sutures or synarthrodial joints
This type of joint is found in the skull. During birth, sutures are flexible to allow the baby to pass through the birth canal, and they become more rigid with age.
Syndesmoses
Found between some long bones like the tibia and fibula.
Gomphosis joints
Attach teeth to the sockets of the maxilla and mandible.
Cartilage
Firm, flexible connective tissue that pads and protects joints and structural components of the body.
Cartilaginous Joints
Moderately movable joints made of fibrocartilage or hyaline cartilage.
Synovial Joints
Fluid-filled joints found between bones that move against one another.
Non-Synovial Joints
Joints that lack a fluid junction.
Articular Capsule
The envelope surrounding a synovial joint.
Synovial Fluid
A viscous fluid found in the cavities of synovial joints.
Arthrokinematics
The broad term meaning joint motion that can be used in reference to all joint motions.
Ball-and-socket joint
Also known as an enarthrodial joint, this joint allows a wide range of movement in many directions.
Saddle joint
The sellar or saddle joints are like ball-and-socket joints but cannot rotate.
Hinge joint
The hinge joints include the elbows, ankles, and knee joints.
Gliding joint
The arthrodial or gliding joints of the body include the tarsals and metatarsal of the foot.
Pivot joint
Trochoidal or pivot joints rotate around a long axis (line that runs parallel to the joint).
Condyloid joint
Also known as an ellipsoid joint, these joints move in two directions—one direction primarily with a small range in another direction.
Close-Packed Joint Position
The most stable joint position, when the connective tissue is taut and neighboring bones have the most contact.
Loose-Packed Joint Position
The less stable joint position represented by any other joint position other than close-packed.
Golgi Tendon Organ
The proprioceptive sensory organ that senses muscle tension in a tendon and inhibits muscle action.
Feedback Loop
The return of a system’s output as input for a future action.
Muscle Spindle
The proprioceptive sensory organ that senses muscle stretch in a muscle and promotes muscle action.
Ligaments
Tough bands of connective tissue made of collagen and elastin connecting bone to bone.
Elastin
A highly elastic connective tissue allowing many tissues to retain their shape.
Varus
An abnormal joint movement away from the midline of the body (i.e., bowlegged).
Joint Capsule
A thin, strong layer of connective tissue containing synovial fluid in freely moving joints.
Valgus
An abnormal joint movement toward the midline of the body (i.e., knock-kneed).
Extrinsic ligament
This type of ligament is located on the outside of the joint.
Intrinsic ligament
the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) are situated inside the knee joint to resist anterior and posterior (forward and backward) movement of the tibia, respectively.
Capsular ligament
The medial collateral ligament (MCL) is a capsular ligament, so called because it is continuous with the joint capsule. It resists valgus stress at the knee by keeping the joint approximated.
Perichondrium
The connective tissue enveloping cartilage everywhere except at a joint.
Articular Cartilage
A form of hyaline cartilage located on the joint surface of bones.
Nociceptors
Pain-sensitive nerve endings
Hyaline Cartilage
A transparent cartilage found on most joint surfaces and in the respiratory tract, which contains no nerves or blood vessels.
Fibrocartilage
An elastic and tough tissue containing type I and type II collagen.
Meniscus
A form of fibrocartilage present in the knee, wrist, acromioclavicular, sternoclavicular, and temporomandibular joints.
Elastic Cartilage
Flexible cartilage present in the outer ear, inner ear, and epiglottis.
Epiglottis
A piece of elastic cartilage in the throat that opens during breathing and closes during swallowing.
