by ANS205


keywords:
Bookmark and Share



Front Back
Sarcolemma
the outer cell membrane of a muscle fiber
Myofibril
elongated protein strands inside the muscle cell fiber
Sarcoplasmic Reticulum
the smooth ER that fills the clefts/space between myofibrils in the muscle fiber
T-tubles
(transverse systems) are tubular invaginations formed by the sarcolemma that propagate action potential to the inside of the cell
Sarcomere
the sarcomere is the functional unit of muscle contraction that boes from one z line to the next and includes part of the I band (light zone), the zone of overlap, the h zone and m line (dark zone) and part of the next I band
M Line
the transverse line at the midpoint of the sarcomere. The M-line consists of proteins that connect the thick filaments at their midpoint
H Zone
includes the M line which is made up of proteins that connect the thick filaments at their midpoint
Z Line
A region of muscle sarcomere to which the plus ends of actin filaments are attached. It appears as a dark transverse line in micrographs
A Band
The A bands are bisected by the H zone running through the center of which is the M line
I Band
The I bands are bisected by the Z line
Action Potential
short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a stereotyped trajectory. Action potentials occur in several types of excitable cells, including neurons, muscle cells, and endocrine cells
Neuromuscular Junction
the synapse space between the terminal of a motor neuron and the membrane of a muscle fiber. Nerve impulses are transmitted across the gap by diffusion of a transmitter
Ligand-gated Channel
group of transmembrane ion channels that are opened or closed in response to the binding of a chemical messenger (i.e., a ligand), such as a neurotransmitter. Ex. acetylcholine binds to the channels to allow Na+ to flow into the cell
Ion-gated Channel
group of transmembrane proteins that are open or closed in response to the binding of a chemical messenger
Synaptic Cleft
Chemical synapses are specialized junctions through which neurons signal to each other and to non-neuronal cells such as those in muscles or glands. Chemical synapses allow neurons to form circuits within the central nervous system
Pre-synaptic membrane
the membrane on the cell receiving the original action potential from a stimulus. Transmits the chemical signal to the Post synaptic membrane (membrane on the cell receiving the signal)
Acetylcholine
The chemical compound acetylcholine (often abbreviated ACh) is a neurotransmitter in both the peripheral nervous system (PNS) and central nervous system (CNS). Is released at the ends of nervous fibers
Acetylcholinesterase
also known as AChE, is an enzyme that degrades (through its hydrolytic activity) the neurotransmitter acetylcholine, producing choline and an acetate group. Is an enzyme in the membrane of the post-synaptic cells
Cell Signaling
Cell communication, any of several ways in which living cells of an organism communicate with one another, whether by direct contact between cells or by means of chemical signals carried by neurotransmitter substances, hormones, and cyclic AMP
What are the three structural proteins that make up thin filaments
tropomyosin, troponin, actin
What is the structural protein of thick filament
myosin
What are the four types of energy supply used by muscles
ATP, CP, Glucose, lactic acid + oxygen
What is the source of calcium in skeletal muscles
sarcoplasmic reticulum
What is the use of calcium in skeletal muscle
binds to the troponin and causes movement to allow binding of myosin
What is the source of calcium in smooth muscle
sarcoplasmic reticulum inside the cell and through channels from outside the cell
What is the use of calcium in smooth muscle
binds to calmodulin, forms a complex, binds to MLCK, phosphorylates
What is the source of calcium in cardiac muscle
sarcoplasmic reticulum and through channels from outside the cell
What is the use of calcium in cardiac muscle
binds similar to skeletal muscle (to the troponin)
Tetanus is caused by a ______ produced by bacteria (clostridium tetani)
neurotoxin
Tetanus is caused by loss of control of excitatory impulses which causes continuous ___ ____ spasms
tonic muscle
Botulism is caused by a toxin produced by _______ _____ which acts on neuromuscular junctions
clostridium botulinum
In botulism, the toxin prevents the ____ containing Ach from releasing at the synapse
vesicles
Botulism is flaccid paralysis due to lack of muscle _______
contraction
Rigor and Rigor Mortis occurs when most of the _____ is depleted and the myosin heads cannot separate from the actin because calcium is not sequestered back into the SR
ATP
Continuous contraction of muscle will eventually lead to
liquefaction
Fatigue is a function of the _____ cell
muscle
Fatigue is from a decrease in ____ availability
ATP
Fatigue is due to a buildup of ______ such as lactic acid from the use of energy in a cell
metabolites
x of y cards