The myosin head stays bound until a new ATP molecule binds to it. The next ATP causes the head to be released from the actin, which results in another power stroke. The stimulus stops. Ach is diffused through the synaptic cleft, CA2+ is transported back into the sarcoplasmic reticulum, and tropomyosin shifts to conceal the myosin binding sites. The sarcomeres slide back to their initial
A. Atrial Natriuretic Hormone B. Anti Diuretic Hormene C. Follicle Stimulating Hormone D. Insulin Like Growth Factor 26. Residual volume is a factor in determining Vital Capacity . True . False 27. What hormone is responsible for decreasing the level of calcium in the blood .
(Calcium ions) are stored in the Sarcoplasmic reticulum. 4. The cause for the release of Calcium is the depolarization of the T-tubules. (Acetylcholine enters the synaptic cleft gap and opens the chemically gated sodium channel that starts an action potential spreading down the sarcolemma of the myofibril. This will cause an action potential to spread down to the T- tubules and “electrical chemical signals = shocks” the sarcoplasmic reticulum into releasing calcium ions.
3. What type of chemical bonds are found in this molecule? Describe the structure of those bonds. 4. As mentioned in the case description, tetrodotoxin is a molecule that blocks voltage-gated sodium ion channels.
An action potential arriving at the presynaptic membrane causes Ca+2 ions to flow through channels into the cytosol. What affect does this have on the vesicles containing neurotransmitters? The presence of Ca+2 ions brings about the release of neurotransmitter from its vesicles. 10. What do the neurotransmitter molecules do once they are released into the synaptic cleft?
Then a neurotransmitter, called acetylocholine (ACh), is released and the ACh binds to receptors on motor end plates and sodium ions then move into muscle fibers. The next step is the muscle action potentials move into the Ttubules where calcium is released by the sarcoplasmic reticulum and the calcium binds to a binding
5. The accumulation of sodium inside causes depolarization, which opens the calcium channels. 6. Influx of calcium triggers exocytosis of synaptic vesicles and liberation of neurotransmitter. 7.
| | | |The protein ___myosin____consists of two twisted strands with globular cross-bridges projected outward along the strands. | |__actin___ is a globular protein with myosin binding sites. What two proteins are associated with it? Troponin and tropomyosin | |According to the sliding filament theory of muscle contraction, if allowed to, the myosin crossbridge attaches to the binding site on the actin filament | |and bends, pulling on the actin filament; it then releases and attaches to the next binding site on the actin, pulling again. What is preventing this from| |happening continuously?
Voltage-gated sodium ion channels are made of amino acids and are necessary for the initiation and propagation of action potentials. 6. Why do sodium ions need channels in order to move into and out of cells? Sodium ions need channels in order to move in and out of the cell because to move in and out on the cell the ion has to pass through the plasma membrane. However the plasma membrane works as a barrier separation the cell from the extracellular fluid, and the interior of the plasma membrane contain hydrophobic tails, which blocks the movement of charged ions to move in and out.
The parietal, incisive and temporal bones are a) sesamoid bones b) bones of the skull c) bones of the pelvis d) bones of the carpus 9. The olecranon is part of the a) scapula b) humerus c) radius d) ulna 10. 4. A partially or differentially permeable membrane is called a a) diffusion membrane b) facilitated membrane c) semi-permeable membrane d) non-facilitated membrane Which hormones are responsible for calcium regulation in the body? a) thyroid hormones b) insulin and glucagon c) parathyroid hormone and calcitonin d) glucocorticoids and mineralocorticoids 5.