Contraction and Relaxation of Skeletal Muscle - 1
Contraction and Relaxation of Skeletal Muscle - 2
Metabolism - 1
Metabolism - 2
Chapter 10- Random
100
What does the Contraction Cycle begin with?
SR releasing calcium ions into the muscle cell.
100
The force of a muscle contraction depends on what?
What is length of sarcomeres.
100
How long will ATP inside the muscle fiber already power a contraction?
Only a few seconds- once reserves are used up more ATP must be produced.
100
How long can aerobic respiration produce muscle contractions?
90% of source of ATP for activities over 10min
100
What are the four phases of twitch contractions?
1. Latent period 2. Contraction period 3. Relaxation period 4. Refractory period
200
What are troponin and tropomyosin apart of?
What is thin filaments
200
What are the four MAIN steps in a nerve impulse eliciting an action potential?
1) Release of ACh 2) Activation of ACh receptors 3) Production of muscle action potential 4) Termination of ACh activity
200
What are two things that require large amounts of ATP?
1) Power contraction cycle 2) Pump Ca2+ into SR
200
How much ATP does one glucose molecule yield in aerobic respiration?
36 ATP
200
Define muscle tone.
Small amount of tension in the muscle due to weak muscle contractions of motor units.
300
What are the four steps of the Contraction Cycle?
1) ATP hydrolysis 2) Formation of cross-bridges 3) Power Stroke 4) Detachment of myosin from actin
300
Define Neurotransmitter.
Chemical released by initial cell communicating with second cell.
300
What are the three ways muscle fibers produce ATP?
1) Creatine Phosphate 2) Anaerobic Respiration 3) Anaerobic Respiration
300
What are muscle tissues two sources of oxygen?
1) Hemoglobin in blood 2) Myoglobin in muscle cells
300
Define Isometric contraction.
Tension generated is not enough for the object to be moved, and the muscle does not change its length. (Holding book steady with outstretched arm)
400
What is a synapse?
Where communication occurs between somatic motor neuron and muscle fiber
400
Define Motor End Plate.
Region opposite of the synaptic end bulb; contains ACh receptors
400
What is creatine phosphate and how does it produce ATP? How long of a contraction can it support?
Creatine Phosphate is a high energy molecule. Transfers its high energy phosphate group to ADP to produce ATP - enough for about 15seconds of contraction.
400
What does pyruvic acid in Aerobic respiration produce?
ATP, CO2, H2O and heat
400
Differences between red and white muscle fibers.
Red: High myoglobin content, have more mitochondria, blood supply by more blood capillaries White: Low content of myoglobin
500
What do synaptic vesicles contain?
Neurotransmitter ACh (acetylcholine)
500
What does Botulinum toxin do?
Blocks release of ACh from synaptic vesicles- can cause paralysis of respiratory muscles Used in medicine Botox
500
Simply explain anaerobic respiration.
1) Creatine phosphate is used up, takes glucose from blood and glycogen storage 2) Glucose is broken down through glycolysis into Pyruvic acid 3) Pyruvic acid produces 2 ATP 4) Pyruvic acid can enter aerobic respiration to produce more ATP if needed 5) Anaerobic provides about 30-40 seconds of muscle contraction
500
Name some factors that contribute to muscle fatigue.
1. Lactic acid and ADP build up 2. Failure of motor neuron to release enough ACh 3. Depletion of glycogen and other nutrients 4. Insufficient Oxygen 5. Depletion of Creatine Phosphate 6. Inadequate release of calcium ions from SR
500
What are the three regions cells of a somite differentiate into?
1) Myotome - muscles of head, neck, and limbs 2) Dermatone - forms connective tissues, including dermis of skin 3) Sclerotone - gives rise to the vertebrae
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