A&P – Flashcards

the sheath that surrounds muscle fiber

the sheath that surrounds the whole muscle

the sheath that surrounds a fascice

continuous fused contraction of muscles

motor neuron action potential arrives at the nueromuscular junction. 1. ACH arrives at muscle fiber's plasma membrane causing depolarization 2. the action potential moves through the muscle fiber along transverse (T) tubules. 3.the sacroplamismic reticulum becomes more permeable in response cause a release of CA ions 4.when the tropomyosin shifts positions as calcium ions bind to troponin, actin binding sires are exposed 5.myosin cross bridges attach to actin fibers 6.sarcomeres within the muscle fibers contract

Calcium binds to the troponin-tropomyosin complex, exposing actin's myosin-binding sites.

1. an action potential is produced in the sarcolemma 2. the action potential enter the T tubules 3. calcium channels in the sacroplasmic reticulum open 4. calcium ions flow into the sarcoplasm. 5. calcium ions bind to troponin 6.troponin changes shape 7. tropomyosin moves 8. active sites are exposed on the thin filament 9. the thin and thick filaments bind

Myosin binding to actin through cross bridges causes thin filaments to slide past thick filaments.

More motor neurons and larger motor units are activated to stimulate a greater number of muscle fibers for a stronger muscle contraction.

section of actinin that connects adjacent sacromeres

region of a sarcomere that contains only thin filaments

region of a sarcomere that contains only thick filaments

section of proteins that connect central points of thick filaments

section of a sarcomere that is as long as a thick filament

1. action potential arrives at axon terminal 2. opening of voltage gated calcium channels 3. influx of calcium ions 4. release of ACH from vesicles into synaptic cleft 5. binding of ACH to cholinergic receptors in muscle cells 6. opening of sodium channels causing influx of sodium ions 7. end plate potential in muscle cell

ability to regain shape after stretching or contracting

ability to lengthen and stretch

ability to shorten and increase in width

ability to respond to a stimulus

ability to transmit electrical signal

-changes in the cells membrane potential - Hyperpolarization - depolarization

Conduction occurs exclusively at nodes of Ranvier.

EPSP (excitatory postsynaptic potential spatial summation synaptic potentiation

IPSP (inhibitory postsynaptic potential) presynaptic inhibition

-all or none potential - initiated by voltage- gated channels -irreversible - nondecremental - long distance

-potentials summate - initiated by lion-gated channels - reversible -decremental - size varies -short distance

combination of postsynaptic potentials due to the simultaneous stimulation of multiple synapses

1. action potential is generated in the presynaptic neuron 2. action potential arrives at the axon terminal 3. voltage-gated ca2+ channels in the axon terminal open and ca2+ flows inward down the concentration gradient 4. cytosolic ca2+ stimulates synaptic vesicles to release neurotransmitter via exocytosis 5. neurotransmitters diffuses across the synaptic cleft 6. binding of nuerotransmitter opens ion channels and causes a change in membrane potential 7. neurotransmitter effects are terminated

1. resting state 2. graded potential brings the membrane to threshold potential 3. fast Na+ and slow K+ channels are activated 4 Na+ ruses into cell causing membrane depolarization 5. K+ channels fully open and Na+ channel inactivation gates close 6. K+ ruses out of the cell, causing repolarization 7. return to n

At synapses, axons release neurotransmitters that are recognized by proteins on dendrites.

The nervous system senses stimuli, integrates information, and generates a response.