Exam 1 Flashcards
what is a motor unit
a single alpha motor neuron and all the muscle fibers it innervates
what is the difference between BM & plasmalemma
- plasmalemma is the true cell membrane, transmits action potentials along the length of the cell
- BM is used as structural support to help repair/regenerate structures if neuromuscular junction gets damaged & releases enzymes acetylcholinesterase which breaks down acetylcholine
what is the difference between Type 1 & Type 2 motor units
what is the difference between eccentric & concentric contractions
describe sliding filament theory
process of muscle contraction involving the sliding of actin & myosin myofilaments past each other to shorten the length of each sarcomere
sliding filament theory order of events
- AP reaches axon terminal which causes Ach to be released from vesicles into synaptic cleft
- Ach binds receptors to plasmalemma –> propogate AP along lengthn o fmuscle
- Ca2+ rleasew from SR (T-tujb8ules_P)P
what is syncytia
multiple nuclei exist in each cell
what is the length-tension relationship
what is the rate limiting enzyme in glycolysis
PFK (phosphofructokinase)
what is the rate limiting enzyme in Krebs
isocitrate dehyrogenase
what is the rate limiting enzyme in ETC
cytochrome c oxidase
how many ATP are produced from complete metabolism of glucose
32
how many ATP are produces from the complete metabolism of glycogen
33
what reactions cost an ATP in the 1st phase of glycolysis
- hexokinase (glucose)
- PFK
how many NADH and FADH are produced from the complete metabolism of glucose
10 NADH, 2 FADH
how many NADH and FADH are produced from the complete metabolism of glycogen
how many ATP are derived from NADH and FADH via the ETC
can AMP be used for energy
no
what is AMP’s role in metabolism
AMP controls speed of metabolism by stimulating enzymes PFK and phosphorylase
where does glycolysis occur
cytosol
where does krebs occur
mitochondria
where does ETC occur
mitochondria
which step represents the convergence of glycolysis and glucogenolysis
glucose 6-phosphate
what is the atmospheric air composition?
79% N2, 21% O2, 0.03% CO2
what is ventilatory threshold (VT)
- point at which ventilation increases exponentially because of hydrogen buildup during high intensity exercise
