Muscle- Part 2 Flashcards
What does the sliding of myosin along actin result in?
Shortening of the Sacromere = contraction
Excitation-contraction coupling:
Step 1: ATP binding releases the myosin head from _____?
Actin
Excitation-contraction coupling:
Step 2- What does the hydrolysis of ATP to ADP straighten?
Myosin head
Excitation-contraction coupling:
Step 3- Where does the myosin head bind?
Actin
Excitation-contraction coupling:
Step 4- What happens to the myosin head when ADP is released?
It bends
Excitation-contraction coupling:
What results from low ATP levels and calcium leakage?
Rigor mortis
What is the protein that Ca++ binds to that causes allosteric changes?
Troponin
When Ca++ binds to troponin, what happens that will cause tropomyosin to move away, uncovering the myosin binding sites on the actin filament?
Allosteric change
What are the 4 energy sources for muscle work?
1- ATP, creatine kinase
2- Anaerobic Glycolysis
3- Aerobic Glycolysis
4- Beta-oxidation of fatty acids
What is the name of the Ca++ voltage gated channel located on the SR?
Ryanodine receptor
What is the name of the Ca++ channel located on the T-tubule?
Dihydropyridine receptor (DHP)
What is muscle contraction done by?
Excitation-contraction coupling
What is needed for the myosin head to get out of actin filament?
Release of ADP
If you only need to move for 10-20 seconds, which energy source will you use?
ATP, creatine kinase
If you need energy for a few minutes, what will be the energy source?
Anaerobic glycolysis
