Anatomy Flashcards
Human Anatomy
The study of the structure and location of different
components of the human body
- Gross Anatomy
- Microscopic Anatomy
Gross Anatomy
subdivided into surface anatomy (the external body), regional anatomy (specific regions of the body), and systemic anatomy (specific organ systems).
Microscopic Anatomy
Is subdivided into cytology (the study
of cells) and histology (the study of tissues).
Anatomical Position
- Standardize view the
body - Body standing upright
- Feet at shoulder width
and parallel, toes forward. - Upper limbs are held out
to each side - Palms of the hands face
forward - It reduces confusion: It
does not matter how the
body being described is
oriented, the terms are
used as if it is in
anatomical position
Body Planes (Of Human Body)
- Frontal/Coronal Plane: front and back
- Midsagittal/Median Plane: right and left
- Transverse Plane: upper and bottom
Anterior (or ventral)
Describes the front or direction toward the front of the body. The toes are anterior to the foot.
- Anterior skeleton (FRONT)
Posterior (or dorsal)
Describes the back or direction toward the back of the body. The popliteus is posterior to the patella.
- Posterior skeleton (BACK)
Superior (or cranial)
Describes a position above or higher than another part of the body proper. The orbits are superior to the oris.
- Pelvis superior to legs
Inferior (or caudal)
Describes a position below or lower than another part of the body proper; near or toward the tail (in humans, the coccyx, or lowest part of the spinal column). The pelvis is inferior to the abdomen
- Legs inferior to pelvis
Lateral
Describes the side or direction toward the side of the body. The thumb (pollex) is lateral to the digits.
- Ears lateral to cheeks
Medial
Describes the middle or direction toward the middle of the body. The hallux is the medial toe.
- Cheeks medial to ears
Proximal
Describes a position in a limb that is nearer to the point of attachment or the trunk of the body. The
brachium is proximal to the antebrachium.
- Elbow proximal to hand
Distal
Describes a position in a limb that is farther from the point of attachment or the trunk of the body. The
crus is distal to the femur.
- Hand distal to elbow
Superficial
Describes a position closer to the surface of the body. The skin is superficial to the bones.
Deep
Describes a position farther from the surface of the body. The brain is deep to the skull.
Flexion and Extension (Movement)
- Action: Reduces / increases angle between joint
- Reference: Sagittal plane movement
- Example:Biceps curl
Abduction and Adduction (Movement)
- Action: Away / towards mid line
- Reference: Frontal plane movement
- Example: Jumping jacks
Pronation and Supination (Movement)
- Action: Palm faces posterior / anterior
- Reference: hand and forearm movement
- Example: Holing bowl of soup
Dorsi flexion and Plantar flexion (Movement)
- Action: Foot up / foot plants
- Reference: Sole foot movement
- Example: toe raise
Inversion and Eversion (Movement )
- Action: Sole moves in / out
- Reference: Sole foot movement
- Example: Rolling over ankle
Medial/internal rotation and Lateral/external rotation (Movement)
- Action: Flexed forearm moves in / out
- Reference: Longitudinal axis movement
- Example: opening / closing doors
Short (Bones)
- Function: Shock Absorbers
- Example: Carpals and Tarsals
Long (Bones)
- Function: Levers
- Example: Femur and Humerus
Flat (Bones)
- Function: Protect Organs
- Example: Skull, Scapula, and Ribs
Irregular (Bones)
- Function: Special Function
- Example: Facial bones and Vertebrae
Sesamoid (Bones)
- Function: Change pressure / friction
- Example: Patella
Strong Bone
- Density: UP
- Mineralization: UP
- Porosity: DOWN
Weak Bone
- Density: DOWN
- Mineralization: DOWN
- Porosity: Up
Pivot (Joint Movement)
- Description: One bone rotates around one axis
- Movement: Uniaxial, Flexion-extension
- Examples: Neck
Gliding (Joint Movement)
- Description: Bone surfaces involved are nearly flat
- Movement: Uniaxial, Gliding
- Examples: Acromio-clavicular
Hinge (Joint Movement)
- Description: Convex and concave articulating surfaces
- Movement: Uniaxial, Flexion-extension
- Examples: Elbow
Saddle (Joint Movement)
- Description: Bones set together as in sitting on a horse
- Movement: Biaxial, Flexion-extension, abduction-adduction
- Examples: Thumb
Condyloid (Joint Movement)
- Description: Ovular convex shape and reciprocal concave surfaces
- Movement: Biaxial, Flexion-extension, abduction-adduction
- Examples: Knuckles
Ball and Socket (Joint Movement)
- Description: A rounded bone is fitted into a cup-like receptacle
- Movement: Multiaxial, 3-axis rotation
- Examples: Hip
Sensorimotor System
- Skeletal System
- Muscular System
- Nervous System
Skeletal System
- Supports the body
- Enables movement (with muscular system)
- Cartilage
- Bones
- Joint
Muscular System
- Enables movement (with Skeletal System)
- Helps maintain body temperature
- Skeletal Muscles
- Tendons
Nervous System
- Detects and processes sensory information
- Activates bodily responses
- Brain
- Spinal Cord
- Peripheral Nerves
Joints
- Point of connection between two or more
bones - Ligaments
- Connective tissues
- Provide stability and hold bones together
- Classified by the degree of movement
Cartilaginous Joints (Joint Classification)
- Limited movement
- Absorb shock
- Example: Intervertebral discs
Fibrous Joints (Joint Classification)
- No movement
- Absorb shock
Example: Skull sutures
Synovial Joints (Joint Classification)
- Greatest degree of movement
- Allow movement, most common
- Example: Hip Joint
Synovial Joints
- Joint Capsule
- Joint Cavity
- Hyaline Cartilage
- Extrinsic Ligaments
Joint Capsule
- Surrounds the joint and provides support
- Lined with synovial membrane that secretes synovial fluid
Joint Cavity
- Filled with synovial fluid for lubrication
- Also cushions
Hyaline Cartilage
- Dense white connective tissue that covers and protects the ends of the articulating bones
Extrinsic Ligaments
- Support the joint
- Connect the articulating bones of the joint
Muscle Types
- Skeletal
- Cardiac
- Smooth
Skeletal
- Attached to bone
- Contraction = body movement
- Motor nerve control / voluntary
Cardiac
- Heart contraction / beating
- Very fatigue resistant
- Has own intrinsic beat
- Autonomic nerve control / involuntary
Smooth
- Blood vessels & organs
- Slow and uniform contractions
- Fatigue resistant
- Autonomic nerve control / involuntary
Skeletal Muscle Characteristics
- ORIGIN
- INSERTION
ORIGIN (Proximal Attachment)
- Closer to the centre of the body
- Attached to more stationary parts
INSERTION (distal attachment)
- Away from the centre of the body
- More mobile structures
Muscle Structure
- whole muscle
- fascicle
- fiber
- myofibril
- myofilament
Nervous System
- Brain, spinal cord, and nerves
- Receives sensory information about the body and environment
- Provides motor commands to the muscles
- Plays major role in learning and controlling movements
- Network of cells, tissues, & organs that regulates the
actions and responses of the body - Two major components
- central - CNS
- peripheral - PNS
Central Nervous System
- The “control center” that receives information
from the body, integrates that information, and
sends signals to all part of the body- brain
- spinal cord
- control of movement
Cerebral cortex
- Involved in planning and execution of voluntary
movement - Key regions for motor control:
- Premotor cortex
- Motor cortex
- Somatosensory cortex
Motor & Somatosensory regions
- Cerebral cortex organized in terms of motor and sensory functions of
specific anatomical structures - determines effects of injuries to specific parts of the brain
Cerebellum
- Plays important role in
integration and fine-tuning of movement - Especially involved in the
coordination and timing of
movement
Spinal Cord
Relays messages between brain and periphery
- 31 spinal nerves categorized by region:
- cervical
- thoracic
- lumbar
- sacral
Spinal Cord (Matter)
- Gray matter - cell bodies, interneurons, axons and dendrites
- White matter - axons
- White matter organized into ascending and descending tracts
- Sensory signals enter cord dorsal side
- Motor signals exit cord ventral side
Peripheral Nervous System
- Transmits information to and from the CNS
- Network of nerves that run between the spinal cord and all parts of the body
- Two components
- sensory neurons - afferent
- motor neurons - efferent
Neurons
- Represent the cellular unit in the nervous system
- Cell body (soma)
- Dendrites
- Receive signals from
other neurons
- Receive signals from
- Axon
- Many are surrounded
by a myelin sheath
- Many are surrounded
- Axonal endings
- transmit signals to
other neurons
- transmit signals to
Motor System
- Motor unit: a single motor neuron and
all of the muscle fibers it innervates- Represents smallest functional unit of
neuromuscular system - Each MU has between 10’s - 1000’s of muscle fibers
- MU’s classified by properties
- Fast twitch
- Slow twitch
- Represents smallest functional unit of
Motor System (Muscle Force Gradation)
- Two mechanisms used by the CNS
- Recruitment: varying the number of active motor units
- size principle
- rate coding: varying the stimulation frequency of active motor units
Spinal cord
Control of movement ?
- SC can control some aspects of movement with little or no input from
the brain
- Spinal reflexes
- Mono-synaptic stretch reflex
- Withdrawal reflex
- Crossed extensor reflex
