<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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Answer:
natural selection I guess
Megasporangium tissue gives rise to the female gametophyte.
<h3>What is the name of the diploid tissue that gives rise to the female gametophyte?</h3>
- Three of the four haploid megaspores worsen into antipodal cells interior the female gametophyte.
- The central cell of the female gametophyte contains two cores that when fertilized gotten to be the endosperm.
- Megasporogenesis alludes to the advancement of megaspores from the megasporocyte, the cell that experiences meiosis.
- Meiosis of the megasporocyte core comes about within the arrangement of four haploid megaspore cores.
- In most taxa, meiosis is taken after by cytokinesis, coming about in four megaspore cells.
- This design is named monosporic megasporogene - sis; since of the four megaspores delivered, as it were one of them contributes to the female gametophyte
To learn more about female gametophyte from the given link
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Answer:
You use the metric system
Explanation:
Its used all around the world and what is supposed to be used for scientific results.
One constant kept in this experiment is the amount of food available to the larvae.