week 6 muscular system

Question 1

Muscle cells are filed with _________

Answer 1

myofibrils

Question 2

Myofibrils are filled with

Answer 2

sarcomeres

Question 3

The ryanodine receptor releases __

Answer 3

calcium

Question 4

The ryanodine receptor opens when the _______ receptor opens (depolarizes)

Answer 4

dihydropyridine receptor

Question 5

Troponin & Tropomyosin bound together as one _______ that is found around actin molecules.

Answer 5

protein

Question 6

long fibrous protein like rope:

Answer 6

tropomyosin

Question 7

Globular protein made up of 3 subunits

Answer 7

troponin

Question 8

What are the three subunit of troponin

Answer 8

Tc, Ti, Tt

Question 9

Tt stands for

Answer 9

Troponin-tropomyosin

Question 10

Ti stands for

Answer 10

Troponin – interaction

Question 11

Tc stands for

Answer 11

Troponin – calcium

Question 12

Tc component allows ____ to bind

Answer 12

calcium

Question 13

What is the TTC function

Answer 13

to cover the myosin binding sites on actin

Question 14

The ATP that is attached to the Myosin head can be found in two different format:

Answer 14

ATP form, and ADP Pi form

Question 15

The ATP format of the myosin head is considered

Answer 15

low energy configuration

Question 16

The ADP and Pi format of the myosin head is considered

Answer 16

high energy configuration

Question 17

Skeletal Muscle Activation requires ______ of a nerve

Answer 17

innervation

Question 18

___ permits contraction & its absence ______ contraction

Answer 18

Ca, prevents

Question 19

Neuromuscular Junction Process is the ______ of neurotransmitter and _____ of the muscle

Answer 19

release, innervation

Question 20

Excitation Contraction Coupling is the Release of _____ and ________.

Answer 20

calcium , cross bridge formation

Question 21

Sliding Filament Theory is the ________ aka _____ ______

Answer 21

contraction, power stroke

Question 22

Steps to Neuromuscular junction :

Answer 22

Arrival of action potential -> Opening of voltage gated calcium channel->
Entry of calcium->
Exocytosis of neurotransmitter->
Diffusion of the neurotransmitter across the neuromuscular junction ->
Binding of the neurotransmitter to the receptors on the postsynaptic membrane

Question 23

In the neuromuscular junction the neurotransmitter will ALWAYS be ___________.

Answer 23

Acetylcholine (ACh)

Question 24

The receptor that acetylcholine binds to in the neuromuscular junction is always

Answer 24

Nicotinic Cholinergic Receptor

Question 25

The receptor that acetylcholine binds to in the neuromuscular junction is always

Answer 25

Nicotinic Cholinergic Receptor

Question 26

Steps in E-C coupling :

Answer 26

1. Net entry of Na causes postsynaptic membrane (muscle) to reach threshold. 2. Reaching threshold generates action potential on the postsynaptic membrane. 3. Action potential travels down T-tubules causing the Dihydropyridine receptor to depolarize. 4. The depolarization of the dihydropyridine receptor causes the Ryanodine receptor to open. 5. Calcium is released from the SR and binds to troponin. 6. Binding of calcium to “Tc” portion of Troponin causes the tropomyosin to shift over. 7. Shifting of Troponin-Tropomyocin complex causes myosin binding sites on actin to be exposed. 8. Myosin bind actin (cross bridges form between thick and thin filaments)

Question 27

Sliding filament theory steps:

Answer 27

1. Release of ATP (ADP & Pi)-> causes the myosin head to bend -> power (working) stroke occurs 2. A new ATP molecule comes in and bind myosin head -> causes the thick & thin filaments to detach-> Myosin is in low energy state. 3. Rearrangement / Hydrolysis of ATP into ADP & Pi occurs -> myosin head straightens up (cocked position). Myosin is in high energy state now. 4. If calcium present Thick and Thin filaments form cross bridges again and sliding filament theory occurs again, if Ca not present muscle will relax

Question 28

Smooth muscle contains 3 inactive proteins called ________, ________, & ________

Answer 28

myosin light chain Kinase, calmodulin, & myosin

Question 29

Steps to smooth muscle contraction :

Answer 29

1. Calcium ions enter via voltage dependent/ voltage independent Ca2+ channels and SR (calcium induced calcium release)2. Calcium then binds to calmodulin and activates it. 3. The activated calmodulin activated the myosin light chain kinase enzymes 4. The kinase enzymes then takes ATP and converts it to ADP and Pi 5. The ADP and Pi then attach to the myosin activating it, then cross bridges form and shortening begins

Question 30

Steps to smooth muscle contraction :

Answer 30

1. Calcium ions enter via voltage dependent/ voltage independent Ca2+ channels and SR (calcium induced calcium release)2. Calcium then binds to calmodulin and activates it. 3. The activated calmodulin activated the myosin light chain kinase enzymes 4. The kinase enzymes then takes ATP and converts it to ADP and Pi 5. The ADP and Pi then attach to the myosin activating it, then cross bridges form with actin and shortening begins