Lesson 1 - Anatomical terms & basic structures Flashcards
Body Planes, Anatomical Directions, Bone Tissue, Muscle Terms, Joint Movements
Sagittal Plane
longitudinal plane parallel to the median plane. Divides head, torso, limbs into equal OR unequal left & right parts (not halves)
(Think pinstripes going down the body)
Median Plane
midline longitudinal plane. Divides head & toros into left / right halves.
Mid Sagittal plane will equally divide a structure
Frontal / Coronal Plane
Longitudinal plane that divides body into front / back halves. Not always equal.
Transverse Plane
Horizontal plane perpendicular to longitudinal plane. Divides body into upper (superior) and lower (inferior) halves.
Not always equal
Superior / Cranial
head / neck / torso. the structure is closer to the top of the head (not used in describing limbs) than another structure in the body
Inferior / Caudal
head / neck / torso. the structure is closer to the feet than another structure in the body.
Anterior
the structure is more in front than another structure. Related to Frontal plane.
Posterior / Dorsal
the structure is more in back than another structure. Related to Frontal plane.
Medial
the structure is closer to the median plane than another structure. Related to Median plane.
Lateral
the structure is further from the median plane than another structure. Related to Median plane.
Proximal
only used with limbs, structure is closer to the median plane or root of limb than another structure.
Closer to trunk of body.
Distal
only used with limbs, structure is further from the median plane or root of limb than another structure.
Further from the trunk of the body.
Superficial
External, closer to surface of body
Deep
Internal, further away from the surface of body
Diaphysis
hollow shaft of a long bone. Marrow-filled with a medullary cavity, lined by compact bone, with an external layer of periosteum.
well vascularizes, heals faster.
Compact Bone
hard bone beneath periosteum, mainly found in shaft.
Forms the walls of the diaphysis and is a thin surface on other bones without articular cartilage.
Periosteum
Outermost fibrous layer, supplies blood and nerves to the bone. This is what most skeletal muscles attach to.
highly sensitive life support sheath for bone. fibrous, cellular, vascular. Source of bone cells.
Epiphysis
End of a long bone, mostly made of spongy (cancellous) bone. The articulating surface is lined with 3-5 mm of articular (hyaline) cartilage
Cancellous or Spongy Bone
little cavities allow for shock absorption
very porous - contains red bone marrow (where blood cells are made)
weaker and easier to fracture than compact bone.
A latticed truss made up of trabeculae (interwoven beams of bone), filled with red or yellow marrow and blood vessels. Ideal for dynamic response to weight, posture change, and muscle tension.
Articular Cartilage
highly specialized connective tissue
found at the end of bones (epiphysis)
principal function is to provide smooth movement.
It’s the articulating surface in freely movable joints. Smooth, slippery, porous, malleable, no sensitivity, bloodless.
Visceral Smooth Muscle
Found in the walls of hollow organs (stomach, kidneys, intestines, bladder, uterus, arteries). Mostly involuntary.
Peristalsis - wave like undulating squeezing motion of visceral smooth muscle tissue.
long, non striated, and tapered muscle cells with centrally placed nuclei, surrounded by Plasmalemma. Line the walls of visceral organs. Slow, sustained, rhythmic powerful contractions. Also act as gates (sphincters), regulating flow (think, urine.) Can spontaneously contract, through automatic nerves and hormones.
Cardiac Striated Muscle
pumps blood through the body. makes up the bulk of the heart’s mass, involuntary muscle.
building block of heart muscles, branched (look like tied together bamboo), striated, 1-2 central placed nuclei , surrounded by sarcolemma (cytoplasm). Connects to each other via intercalated discs (junctional complex). Strong rhythmic contractions regulated by special set of impulse conducting muscles (not nerves).
Skeletal Striated Muscle
Form of striated muscle tissue found on bones, part of “voluntary” control of somatic nervous system.
Attached to bones by tendons (bundles of collagen)
long, striated, multi-nucleated, enveloped in Sarcolemma (cell membrane). Only pull, never push. Rapid, brief, and powerful shortenings conducted by nerves (innervation). Lack of nerves (denervation) or resupply will lead to cell death.
Muscle Belly
bulk of muscle mass, collections of skeletal muscle cells. This is where the contraction / pulling happens.
Origin
Generally the larger fixed point of muscle attachment to bone.
Insertion
Generally the smaller fixed point of muscle attachment to bone. Muscle contractions generally move from insertion to origin.
Skeletal Muscle
discrete entity with a belly (muscle mass), and tendons at each end. Surrounded by deep fascia and neurovascular bundles.
Connective Tissue
Includes Dermis (deep layer of skin), Fascia, Tendons, Ligaments.
Fascia means “band”. Primarily collagen.
Superficial fascia
Connective tissue that contains nerves, small vessels, and some large veins. Closer to surface underneath skin.
Deep fascia
Closer to the center or core.
Ensheathes skeletal muscle + supporting nerves and vessels. More sensitive, dense, vascular, and irregular.
Skeletal Muscle Fiber
long narrow cells that often span the length of entire muscle.
Endomysium
Inner layer surrounding individual muscle fibers.
Wraps each individual muscle cell, secures the critical neurovascular structures.
Perimysium
Connective tissue (fascia) that wraps bundles of muscle fibers.
Middle covering of skeletal muscle, wraps nerves, small arteries and veins (neuromuscular bundle)
Epimysium
Outer layer surrounding entire muscle belly. Includes nerves, arteries, and veins.
Fibrous outermost covering of skeletal muscle. Works with perimysium and endomysium to ensure uniform distribution of muscle tension (for contraction, maintains elasticity of muscle.
Tendon
Connects muscle to bone. “muscles get tender”. Tendon attached to Periosteum.
The spots where endomysium, perimysium, and epimysium merge. Secures muscles to attachment sites.
Ligament
Connects bone to bone, or cartilage, or holds together a joint.
Dense regular connective tissue. Binds bone to bone via deep insertions into periosteum and underlying bone
Extension
Increase angle between 2 body parts. Straightening a joint. Related to Sagittal Plane. Extreme, abnormal movement is called hyperextension.
Flexion
Bending a joint, increasing angle between 2 body parts. Related to Sagittal plane
Abduction
Moves a joint / bone away from the midline of the body, hand, or foot. Related to Coronal plane.
Adduction
Moves a joint / bone towards the midline of the body, hand, or foot. Related to Coronal plane.
Rotation
Turning or moving bone about its axis.
Lateral/External Rotation
Rotation away from the body
Medial/Internal Rotation
Rotation towards the body
Circumduction
Making a circle around a fixed point.
Circular movement, made up of flexion —> abduction —> extension —> adduction in sequence.
Supination of Forearm
“Soup-ination”. External rotation of radiohumeral joint. Leaves hand and wrist turned palm up.
Pronation of Forearm
Internal rotation of radiohumeral joint. Leaves hand and wrist turned palm down.
Inversion of Foot
Rotating on median plane. Big toe up. Pinky down. “Lift up on the inside.”
Eversion of Foot
Rotating on median plane. Big toe down. Pinky up.
Plantarflexion of Ankle
Pointing foot down, ballet feet.
Dorsiflexion of Ankle
Pointing foot up, balancing on heels.
Bone Tissue
206 bones in the body, made mostly of calcium phosphate and calcium carbonate.
- Support and protects internal organs
- Muscles pull bone to move the body
- stores calcium, plays a large role in balancing calcium blood-levels
Joint Movement
Muscles contract at origin
Terms used assume anatomical position
a joint is where 2 or more bones meet
