Skeletal muscle
adaptations & organelles
adaptations & organelles
A pigment in muscle fibers that stores oxygen and keeps it handy for 'on demand' use
Myoglobin
Striping found on skeletal muscle fibers
Striations
This is wave of depolarization that spreads over the sarcolemma - caused by the opening of voltage gated Na+ channels
Action potential
Muscle tissue that lacks striations
Smooth muscle
These neuron processes receive input signals from receptors and other neurons
Dendrites
These cells make myelin sheaths in the PNS
Schwann cells
The junction of two neurons
Synapse
Sequesters and releases Ca++ in a muscle fiber
Sarcoplasmic reticulum
This protein has the heads that form cross-bridges during contraction
Myosin
The neurotransmitter released by the axon terminal at the neuromuscular junction
Acetylcholine
Over time, light to moderate intensity (aerobic) exercise will increase the number of these in a muscle, making it more efficient
Mitochondria & blood vessels (capillaries)
Every neuron has exactly one of these output processes
Axons
The immune cell of the CNS
Microglia
This determines whether a neurotransmitter is excitatory or inhibitory
The type of receptor that it binds to
A protein rod made of repeating sequences of myofilaments
Myofibril
Where the sarcomere ends & begins.
(it's not a Shel Silverstein book)
Z disc
The teensy-tiny sliver of space that separates the axon from the muscle fiber
Synaptic cleft
One motor neuron and all of the muscle fibers that it controls
Motor unit
White, fatty material that insulates some axons & speeds up nerve transmission
Myelin
Each one of these cells can wrap myelin around up to 60 axons in the CNS
Oligodendrocytes (these are also your instructor's favorite neuroglia.)
(Yeah, that's right. I have a favorite neuroglial cell type. You mean you don't?)
Short distance depolarization on a dendrite. Will die out if the stimulus isn't sufficiently strong
Graded potential
Storage granules that hold long, branching polymers of glucose. Provide energy to generate ATP when needed.
Glycosome
The light stripe on the sarcomere - where only the thin filaments are found.
I band
Chemically-gated channels on the motor end plate allow entry of this ion, causing an end plate potential
Na+
During high-intensity, short-duration exercise, like sprinting, this metabolic pathway provides the ATP
Anaerobic (glycolytic) pathway
If a 3 foot neuron needs to patch up a protein at the axon terminal, it must be made and imported from this part of the neuron
Cell body (soma)
The pronunciation of the name of this neuroglial cell type drives your instructor batty. They line the fluid filled cavities (ventricles) of the brain. You must pronounce it correctly to get the points.
Ependymal cells
The short period of time after an action potential when a patch of membrane absolutely cannot be stimulated enough to generate another action potential
The absolute refractory period
Conducts action potentials to every myofibril in a muscle fiber
T-tubule
This protein blocks the actin subunits during relaxation so that no cross-bridges can form
Tropomyosin
After the sarcolemma depolarizes, it is reset to its original RMP when gated channels open and allow this ion to leave the cell
K+
The primary reason for muscle fatigue
Ion imbalances
Action potentials are generated here
Axon hillock
These cells are a major component of the Blood-Brain barrier
Astrocytes
Nerve impulses on myelinated axons jump from myelin sheath gap to myelin sheath gap
Saltatory conduction