<span>There are numerous proteins in muscle. The main two are thin actin filaments and thick myosin filaments. Thin filaments form a scaffold that thick filaments crawl up. There are many regulatory proteins such as troponin I, troponin C, and tropomyosin. There are also proteins that stabilize the cells and anchor the filaments to other cellular structures. A prime example of this is dystrophin. This protein is thought to stabilize the cell membrane during contraction and prevent it from breaking. Those who lack completely lack dystrophin have a disorder known as Duchene muscular dystrophy. This disease is characterized by muscle wasting begininng in at a young age and usually results in death by the mid 20s. The sarcomere is the repeating unit of skeletal muscle.
Muscle cells contract by interactions of myosin heads on thick filament with actin monomers on thin filament. The myosin heads bind tightly to actin monomers until ATP binds to the myosin. This causes the release of the myosin head, which subsequently swings foward and associates with an actin monomer further up the thin filament. Hydrolysis and of ATP and the release of ADP and a phosphate allows the mysosin head to pull the thick filament up the thin filament. There are roughly 500 myosin heads on each thick filament and when they repeatedly move up the thin filament, the muscle contracts. There are many regulatory proteins of this contraction. For example, troponin I, troponin C, and tropomyosin form a regulatory switch that blocks myosin heads from binding to actin monomers until a nerve impulse stimulates an influx of calcium. This causes the switch to allow the myosin to bind to the actin and allows the muscle to contract. </span><span>
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i believe the answer is b radioactive nucleotide
Answer:
C. Metalloid
Explanation:
<h3>I believe that's the answer, correct me if I'm wrong. </h3>
Answer:
What is the difference between Metaphase 1 and Metaphase 2? In Metaphase I, the 'pairs of chromosomes' are arranged on the Metaphase plate while, in the Metaphase II, the 'chromosomes' are arranged on the metaphase plate. In Metaphase I, the spindle fibers get attached to two centromeres of each homologous chromosome.
In metaphase 1 the pairs of chromosomes referred to as bivalents are totally condensed. Moreover the in metaphase 1 of meiosis there is no centromere division whereas in metaphase of mitosis it does. They align on the metaphase plate in between the poles.
Explanation:
Answer: Decomposers
Because, when organisms are broken down and decomposed, they are mixed in with the soil. Yes, you should add soil to a food web that depicts the food relationship in an ecosystem because not only is it a result of decomposition, it helps the producers grow, starting the food chain again.
