Exam one Flashcards
Layers of Skeletal Muscle
- Muscle belly
- Fascicules
- Muscle fibers
- Sarcomeres
Layers of CT
Epimysium
Perimysium
Endomysium
Structures and Organelles within Skeletal fibers (6)
Plasmalemma/Sarcolemma Satellite cells Nucleus Sarcoplasm T-Tubules Sarcoplasmic Reticulum
Steps of Sliding Filament Theory (starting with neuron)
relaxed state- myosin and Actin are not interacting
Calcium binds to troponin, tropomyosin moves
Power stroke- the myosin head attaches to actin and pull towards center of the sarcomere
-cross bridge
What step in Sliding Filament Theory require ATP?
ATP is require after the power stroke to detach the myosin head from the actin
Factors that determine skeletal muscles recruitment and generation of force
all or none principle
motor unit and muscle size
frequency
Difference between Type 1 and Type 2 muscle fibers
type 1- slow twitch
type 2- fast twitch, type 1A 25%, type 1X 25% fastest twitch
What capacity do the fibers have to change?
very limited only around 10%
What happens to Type 2x fibers with training?
with training some 2A are able to be turned into 2X
How are the fiber types distributed in most humans?
determined at birth 50%/50%
Primary purpose of Kinase and Dehydrogenase enzymes?
catalyzes
Rate-limiting enzymes of the bioenergetics pathways (factors that speed/slow them down)
- isocitrate dehydrogenase
- monophosphate dehydrogenase
Difference between aerobic and anaerobic energy systems
aerobic-oxygen
anaerobic- does not require oxygen
Enzymes and molecules involved in the ATP-PCr system
ADP+ADP=ATP+AMP
catalyzed by Adenylate Kinase
Creatine Phosphate
What part of the cell does glycolysis, krebs cycle, and ETC occur
Mitocondria
Which energy system dominate during different intensities (and the time amount)
ATP-PCr system- 3-15 sec
Glycolysis- 30-120 sec
Aerobic energy systems last longer than anaerobic
What determines if lactate/pyruvate is formed at the end of glycolysis
if it is done the absence of oxygen or not
List different things that can happen to pyruvate and lactate, where they can be used?
- can be moved to other muscles (Lactate shuffle)
- Cori Cycle: converted to pyruvate or glucose in the liver
- Heart and Brain: is able to use lactate as fuel
What happens in the last 2 steps of ETC?
production of H2O and ATP
How can protein fit into different bioenergetic pathways?
each amino acid can perform a different part in the bioenergetic pathway
How much energy is stored within 1 g of dietary carbohydrate, protein, and fat?
Carbs- 4
Protein- 4
Fat- 9
Describe the two shuttles that transport NADH from the cytoplasm into the mitochondria. (where and how it affects ATP net gain)
Skeletal and Brain- H from NADH is moved to FADH in the mitochondria leads to 1 less ATP
Malate-Aspartate Shuttle (heart and liver)- no ATP to be lost
