Week 2 Day 3 Muscle Basics, CrossBridge cycle, controlling skeletal muscles, ATP, Fatigue Flashcards
What does the latin root myo mean?
Pertaining to muscle
What does the latin root sarco mean?
Latin for flesh, referring to part of the muscle cells
Are skeletal muscles involuntary or voluntary contraction?
Voluntary contraction
Muscle Fiber is composed of many _____?
Myofibrils
Are skeletal muscles mononucleated or multinucleated?
Multinucleated.
Can skeletal muscles undergo mitosis?
No, they can’t undergo mitosis but then can go through hypertrophy (grow)
What is a sarcoplasm?
The cytoplasm of a muscle fiber
Waht is a sarcoplasmic reticulum?
the endoplasmic reticulum of a muscle fiber (stores CA)
What is the sarcolemma?
The plasma membrane of a muscle fiber
What is a sarcomere?
A contractile unit
On a muscle fiber, what is a Z line to Z line?
A sarcomere
What protein is thick filaments made of?
Myosin
On a thick filament, what are the two binding sites it has
ATP and Actin binding sites
On thin filaments, what binds to Troponin (protein) and what does does it do?
Ca2+ binds to troponin and uncoils the Tropomyosin, which blocks the Actin from binding to myosin (protein)
What binds to myosin for thin filaments?
Actin
When myosin binds to actin, what happens to the Zline? What is this process called?
The Z lines get closer to each other and spaces are eliminated.
-Crossbridges
What is the cross bridge cycle?
The process of energized Myosin heads (jazz hands) that exist as ADP . Basically the cross bridge cycle is the process of myosin binding and unbinding to actin
What happens to our skeletal muscles when we die?
No ATP is produced and the skeletal muscles contract.
What two things does the cross-bridge cycle require?
ATP and Ca2+
What is the NMJ in between?
A motor neuron and a muscle fiber
How does the larger surface area of a skeletal muscle fiber affect depolarization, glucose, and atp
This makes depolarization take longer and it could hold more glucose and ATP
What is isometric twitches as it pertains to muscle fibers. Give an example with dumbbells
Contraction without changing the length of the muscle.
-When you pick up dumbbells and do a farmers walk with them in your hands and arms to the side of your body
What is isotonic twitches? Give an example with dumbbells
When contraction shortens your muscles.
-When you do you a bicep curl with dumbbells
What are the 3 ways muscles get ATP?
- Creatine phosphate (CP + ADP—> ATP+C)
- Oxidative phosphorylation (adding phosphate) of ADP in mitochondria
- Glycolysis (anaerobic- does not require oxygen)
