Chapter 2 – Functional Anatomy and Training Instruction Flashcards
Homeostasis
The body’s tendency to seek a constant, desirable range of conditions that maintain equilibrium within all physiological systems.
Bone mineral density
The mineral content in a given volume of bone, used as a measure of bone health as well as to diagnose diseases, such as osteoporosis.
Osteopenia
A pre-disease condition, which indicates bone mineral density is lower than normal for a given individual’s age and sex, but is not yet low enough to be classified as osteoporosis.
Osteoporosis
A bone disease in which a decrease in mineral density causes skeletal structures to become brittle and fragile, often leading to fractures and disability.
Osteoblast function
synthesizing bone
Osteocyte function
bone cells synthesized from osteoblasts
Osteoclast function
breaks down bone tissues for remodeling
Epiphyseal plates
The transverse cartilage plates, located near the end of long bones and responsible for increases in vertical growth during childhood and
adolescence.
Bone mass
This represents the surface area of bone and total tissue volume.
Weight-bearing physical activity
Activities where the skeleton must bear the weight of the body while performing the movement; these activity types are favored for improvements in bone mass, strength, and resilience.
Joint
A point of articulation between two or more bones that allows for a functional connection and various amounts of motion, depending on local anatomical features.
Synovial joint
A type of joint that uses synovial fluid to reduce frictional stresses and allow for considerable movement between the associated articulating bones.
Hyaline cartilage
Tough yet elastic connective tissue found in various parts/joints of the body which allows for minimal movement, depending on the surrounding anatomy.
Fibrocartilage
Tough connective tissue composed of a dense matrix of fibers serving as a shock absorber for structures exposed to high forces.
Joint capsule
A connective tissue enclosure that surrounds specific joints and consists of an outer fibrous membrane and an inner synovial membrane, assisting in joint protection and stability.
Periosteum
A dense fibrous membrane covering the surface of bones that serves as an attachment site for tendons to connect muscle to bone.
Synovial membrane
A special membrane that lines synovial joints and secretes synovial fluid to lubricate the articulating surfaces.
Bursa
A small fluid-filled sac that reduces friction between connective and bony tissues during movement.
Ligaments
Tough fibrous bands of connective tissue that support internal organs and attach adjacent bones at articulation sites; due to limited blood supply, self repair is difficult following an injury.
Tendons
Tough fibrous bands of connective tissue that connect muscles to bones; tendons positively adapt to flexibility and resistance-based exercise.
Plane Joint
A plane joint allows bones to slide past each other. Midcarpal and midtarsal joints are plane joints.
Pivot Joint
A pivot joint allows rotation around an axis. Pivot joints are found in the neck and forearm.
Hinge Joint
A hinge joint allows extension and retraction of an appendage. Hinge joints are found in the knees, elbows, fingers, and toes.
Condyloid Joint
A condyloid joint is similar to ball and socket but with less movement. The wrist is a condyloid joint.
Saddle Joint
A saddle joint allows movement back and forth and up and down. The only saddle joint in the human body is the thumb.
Ball-and-socket Joint
A ball and socket joint allows for radical movement in almost any direction. Ball-and-socket joints are found in the shoulders and hips.
Proprioceptors
Special sensory receptors found in joints and connective tissues that send signals concerning body position and movement to motor neurons in the spinal cord, thereby effectively managing muscle and tendon tension.
Hypermobility
Also known as “joint laxity”, this term indicates joint movement capabilities which surpass a normal, healthy range; addressing hypermobility usually requires an emphasis on strength and stability, while avoiding flexibility activities to reduce the risk for injury.
Golgi tendon organs
Special kinesthetic receptors located near muscle-tendon junctions which send reflexive signals to the spinal cord
to regulate muscle tension; they function to protect tissue from overstraining and injury using autogenic inhibition.
Skeletal muscle
A type of striated muscle which attaches to the skeleton to facilitate movements by applying force to bones and joints via contractions.
Cardiac muscle
A type of involuntary, mononucleated, striated muscle found exclusively within the heart.
Smooth muscle
A type of involuntary, non-striated muscle found within the walls of organs and vascular structures.
Fascia
The most superficial layer of muscle composed of a fibrous connective tissue that encapsulates the underlying layers to form individual muscles.
Epimysium
A dense collection of collagen fibers that covers the entire surface of muscle.
Perimysium
A layer of tissue below the epimysium That encompasses bundles of fibers.
Fascicle
A bundle of wrapped muscle fibers.
Endomysium
A thin sheath of connective tissue that covers each separate muscle fiber within a fascicle.
Sarcolemma
The external lamina of each single muscle fiber.
Sarcoplasm
The cytoplasm within each single muscle fiber.
Mitochondria
An organelle responsible for significant energy production and metabolic processes within each cell.
Myofibrils
The sectional units found within each muscle fiber which contain bundles of myofilaments.
Myofilaments
The long, cylinder-like protein elements in muscle tissue which operationally set the action of contraction into motion.
Sarcoplasm
The cytoplasm within each single muscle fiber.
Actin
The thin myofilament within sarcomeres used to create tension inside muscle cells.
Myosin
The thick myofilament within sarcomeres used to create tension inside muscle cells.
Central nervous system
The central processing unit for the nervous system, consisting of the brain and spinal cord.
Action potential
A wave-like change in the electrical properties of a cell membrane that functions as a signal to promote a cascade of events including muscular contraction.
Peripheral nervous system
The portion of the nervous system outside of the brain and spinal cord.
Capillaries
The tiny vascular structures that connect arteries and veins.
Sliding filament theory
This explains the molecular mechanisms surrounding the multi-step interaction between actin (thin myofilament) and myosin (thick myofilaments) during a muscular contraction.
Motor neuron
A nerve cell within the peripheral nervous system that propagates electrical impulses to working musculature to regulate contractions and bodily movement.
Motor unit
A motor neuron and all of the muscle fibers it innervates.
Neuromuscular junction
This is also known as the motor end plate: a junction where a motor neuron and muscle cells interact via chemo-electrical impulses to facilitate the stimulation of muscle cell contraction.
Excitation-contraction coupling
This describes the process in which an action potential propagates across the sarcolemma triggering release of calcium by the sarcoplasmic reticulum to initiate a muscular contraction.
Sarcoplasmic reticulum
The tubular network that surrounds each individual muscle fiber and acts as a storage site for calcium to play its part in facilitating contractions.
Sarcomere
The repeating functional units of a muscle fiber, consisting of contractile myofilaments; sarcomeres are the muscle components which shorten and re-lengthen during contractions.
