Factors of Muscle Contractions 3
What is the ratio of thick to thin filaments in Skeletal muscles?
1:2
How fast is ATP reserve depleted when you start physical activity?
4-6 seconds.
Muscles contract faster/slower than they relax.
Faster
What percentage of ATP is made from Aerobic respiration.
95%
What is the ratio of thick to thin filaments in smooth muscles?
1:13
What is Fatigue?
The physiological inability to contract despite continued stimulation
What is a Muscle Twitch?
Simplest contraction resulting from a muscle fiber’s response to a single action potential from motor neuron
Why must ATP be replenished quickly specifically in muscle cells?
Because unlike other cells, muscle cells can only be powered by ATP.
Aerobic exercise can lead to increase in the number of Mitochondria in muscle cells Why would you want more Mitochondria?
Mitochondria are the powerhouses of the cell and provide power for all basic cell functions.
What type of muscles can contract further and with more fore: Skeletal or Smooth? Explain your answer.
Skeletal muscles because they have a higher ratio of thick to thin filaments allowing for more cross-bridging.
What is the stress-relaxation response in smooth muscles?
Unique ability of smooth muscles to respond to stretching only briefly, then adapt to new length
What are the three ways that ATP can be replenished in muscles cells?
1. Direct phosphorylation of ADP by CP
2. Anaerobic pathway using glycolysis
3. Aerobic pathway using mitochondria
Aerobic exercise can lead to increase in Myoglobin. Why would you want more Myoglobin?
Myoglobin are a muscle cell specific protein that bind, stores, and transports oxygen. The more Myoglobin you have, the more oxygen you can get to your cells
What are three differences between Smooth and Skeletal muscles?
They are thinner and shorter compared to skeletal muscle fibers.
They have only one nucleus, and do not have striations.
They do not have connective tissue sheaths.
They contain varicosities (bulbous swellings) of nerve fibers instead of neuromuscular junctions.
SR is less developed than in skeletal muscle.
Sarcolemma contains pouchlike infoldings called caveolae.
Smooth muscle fibers are usually electrically connected via gap junctions whereas skeletal muscle fibers are electrically isolated.
There are no striations and no sarcomeres, but they do contain overlapping thick and thin filaments.
What happens during Aerobic Respiration in mitochondria?
ATP is made through a series of chemical reactions in the mitochondria of cells.
What happens during Direct Phosphorylation of ADP by CP?
Creatine Phosphate brings one phosphate molecule to ADP to recharge it into ATP.
Aerobic exercise can lead to increase in Muscle Capillaries. Why would you want more Muscle Capillaries?
Capillaries is where oxygen and deoxygenated blood is exchanged. The more you have, the faster blood can flow through the muscles.
Since smooth muscles cannot be controlled manually, what Regulates smooth muscle contractions?
Nerves, hormones, and or local chemistry changes.
What is EPOC and why is it necessary?
Excess post-exercise oxygen consumption
Necessary because once physical activity ends, all pathways that replenish ATP require oxygen.
What happens in the Anaerobic pathway with Glycolysis
Glucose is quickly turned into ATP creating lactic acid as a byproduct.