ANAT EXAM 4

Muscular system

F: movement, posture, joint stability, heat (waster product during contraction)

Connective tissues

comprised of collagen and elastic fibers

F: protection, hold together, sites for blood vessels and nerves, attachment of muscle to skeleton

fascia

connective tissue that connects muscles to skin or other muscles

Fascicle

group of structurally and functionally related cells and their ECM

excitability

responds to stimulus, change in membrane potential

contractability

proteins in muscle cells draw together (sarcomere)

conductivity

electrical changes across membrane conduct membrane

action

body movement because of a muscle contraction

innervate

to supply a muscle with nerves

insertion

muscle attachment point that will move the structure to which it is attached when the muscle contracts

origin

relatively stationary attachment points of a muscle

agonist

muscle that contracts to produce a particular movement

antagonist

muscle that opposes the action of its agonist partner

synergist

muscles that aid the action of the agonist by guiding the movement to ensure a smooth action

fixators

muscles that stabilize the bone during an action

Sternocleidomastoid

Manubrium of sternum, medial portion of clavicle

Mastoid process of temporal bone

Together: flex head; individual: flex and rotate head toward the opposite side. Accessory muscles of inspiration

Trapezius

External occipital protuberance, cervical vertebra, spinous processes of thoracic vertebra

Lateral clavicle & spine and acromion of scapula

elevates scapula, rotates scapula superiorly

Rectus abdominus

superior aspect of pubis bones

costal cartilages of inferior ribs

flexes the trunk, compresses abdominal cavity

Pectoralis major

Medial clavicle, sternum, costal cartilages 1-7

Greater tubercle & lateral lip of intertubercle sulcus of humerus

Flexes and adducts the arm, rotates the arm medially

deltoid

Acromion & spine of scapula; lateral clavicle

Deltoid tuberosity of humerus

Abducts the arm; secondarily flexes and extends arm

triceps brachii

olecranon process of ulna

extends the forearm

biceps brachii

Supraglenoid tubercle & coracoid process of scapula

radial tuberosity of radius

flexes the forearm, supinates the forearm

gluteus maximus

Posterior & lateral portions of ilium, sacrum & coccyx

Gluteal tuberosity of femur

Rotates the thigh laterally, abducts the thigh, extends the thigh

Adductor longus

Body of pubis

Linea aspera of femur

adducts the thigh, flexes the thigh, rotates the thigh medially

Gastrocnemius

Medial and lateral condyles of femur

Posterior calcaneus

Plantarflexes the food, flexes the leg

Tibialis anterior

Lateral condyle of tibia primarily

Tarsal and 1st metatarsal

dorsiflex the food, invert food

Rectus femoris

Anterior inferior iliac spine, superior margin of acetabulum

Patella and tibial tuberosity

Extends the leg, flexes the thigh at hip

Biceps femoris

Ischial tuberosity & distal half of posterior femur

Head of fibula; lateral condyle of tibia

Extend the thigh, flexes the leg

skeletal muscle

sarcomere

stimulated by nervous system for contraction

cardiac muscle

gap junctions in intercalated discs - coordinate contraction

autorhythmic - generate muscle impulse without nervous stimulation

sarcomere

smooth muscle

thin filaments attached to dense bodies

cells physically coupled at dense bodies

contraction: myosin heads opposite facing, long and thin cells to fat globs

Gap junctions

First class lever

Fulcrum in middle

Second class lever

Load in middle

Fulcrum close to load

Mechanical advantage because large load is moved with small force

Third class load

Force in middle

Most motion

Sensory receptors

perceive stimuli

effectors

carry out effects of nervous system

Sensory (afferent)

carry signals from sensory receptors to CNS

Motor (efferent)

carry signals from CNS to muscles or glands

Interneuron

Between sensory and motor neurons

Neuroglia

Nerve glue

specialized support cells for neurons

Astrocytes

anchors neurons and blood vessels, clean up excess chemicals, facilitate formation of blood brain barrier CNS

oligodendrocytes

form myelin sheath CNS

microglia

phagocytes, eat stuff CNS

ependymal cells

produce and circulate cerebrospinal fluid CNS

Schwann cells

form myelin sheath PNS

Satellite cells

surround and support cell body PNS

Nerves

Bundle of neuron axons packed with blood vessels and myelin sheath

F: carry signals to and from CNS

sensory nerves

contain sensory neurons

F: carries signal from sensory receptor to CNS

Motor nerves

Contain mostly motor neurons

F: carry signal from CNS to muscles or glands (effectors)

PNS Somatic Sensory division (voluntary afferent)

sensory neurons carry general sensory signals from muscles, bones, joints, and the skin as well as special sensory signals to CNA

PNS Visceral Sensory division (involuntary afferent)

Sensory neurons carry signals from organs (viscera) to CNS

PNS Somatic Motor division (voluntary efferent)

Motor neurons carry signals from CNS to skeletal muscles

PNS Visceral Motor Division / Autonomic Nervous System (involuntary efferent)

parasympathetic and sympathetic motor neurons carry signals from CNS to smooth muscle, cardiac muscle, and glands (viscera)

Sympathetic

Fight or flight, maintains homeostasis during exercise, emotions, emergency

Parasympathetic

digest and rest, homeostasis of maintenance functions such as digestion and formation of urine during rest

Acetylcholine

regulates muscle contraction, parasympathetic NS, some brain functions

norepinephrine / epinephrine (adrenaline)

influences heart rate, blood pressure, digestion, regulates sleep / wake cycle, attention, feeding

dopamine

coordinate movement, involved in emotions and motivation

serotonin

mood regulation, affects emotion, attention, cognition, motor behavior feeding behavior, daily rhythms

histamine

regulation of arousal and attention, mediates allergic responses

neuromodulation

alter synaptic transmission (strengthen or weaken effect of neurotransmitter)

Cerebrum

Performs higher mental functions

Interprets sensory stimuli

Plans and initiates movement

Diencephalon

Processes, integrates, and relays info

Maintains homeostasis

Regulates biological rhythms

Cerebellum

Monitors and coordinates movement

Brainstem

Maintains homeostasis

Controls certain reflexes

Monitors movement

Integrates and relays information

Dura Mater

Superficial (outer) meningeal layer

Connects to bone

Meninges

connective tissue surrounding brains and spinal cord

F: protection

Arachnoid Mater

Middle loose meningral layer

Pia Mater

Deepest thin meningeal layer vascular, clings to grooves of cortex

Grey Matter

Cell bodies, dendrites, interneurons

Generally forms the cortex

F: process information

Develops by 20s

No myelin

White matter

Myelinated axons

deep to brain structures

F: communication to and from grey areas and between gray areas and rest of body

developments peaks middle age

Ventricles

F: hollow spaces in brains filled with cerebrospinal fluid

Lateral Ventricle (first and second)

horns

Third ventricle

head

founrth ventricle

neck

Cerebrospinal Fluid

F: Provides buoyancy, protects brain, regulates environment of CNS (nutrient and waste transport)

Blood brain barrier

barrier between blood and neurons in brain

property of capillaries in brain

only lets certain things in

Frontal Lobe

voluntary motor function

Parietal Lobe

General sensory function

Temporal Lobe

Hearing and smell

Occipital lobe

process incoming visual info and stores visual memories

Insula Lobe

Memory and interpret taste (inside of frontal and temporal)

Somatosensory cortex

interprets incoming somatic sensory stimuli (temperature and touch)

Primary motor cortex / premotor cortex

plans and executes movement (complex = premotor)

Upper motor neurons

plan movement

Wernicke’s area

language comprehension

Broca’s Area

Language production

Limbic System

Hippocampus: Memory and learning

Amygdala: Behavioral expression and emotion

Basal nuclei

regulates voluntary movement

Cerebral cortex

Primary motor cortex: plans and executes voluntary moments \

Primary sensory cortices: receive and process different types of sensory input

Multiple task association areas: integrate sensory and motor info from a variety of different primary cortex

Subthalamus

Regulates voluntary movement

Hypothalamus

Regulates autonomic NS

Regulates sleep/wake cycle

Regulates thirst and hunger

Regulates body temp

Controls secretion from pituitary gland

Epithalamus

Produces melatonin

Thalamus

Controls sensory information entry into the cerebral cortex

Edits, sorts and routs stimuli

Cerebellum

Coordinates ongoing voluntary movement to reduce motor error

Midbrain

Processes and routs visual and auditory stimuli to the thalamus

Carries motor fibers from the cerebral cortex

Monitors movement with the basal nuclei

Mediates reflexes

Pons

Regulates breathing and sleep/wake cycle

Medulla oblongata

regulates autonomic functions (HR, breathing BP)

Nuclei of cranial nerves

Reticular formation

Inside of medulla oblongata, involved in sleep and arousal, pain transmission

Plays a role in mood regulation

Maintains homeostasis of many variables

All regions of Brainstem

Contain tracts of white matter involved in movement and sensation, route for ascending and descending tracts between cerebellum and spinal cord