Answer:
The correct option is C. Motor neuron does not fire action potentials
Explanation:
During contraction, the motor nerve passes down an action potential. A neuromuscular junction is formed by the motor neuron which stimulates the entry of calcium ions. The calcium ions bind to structures called as troponin which stimulates the binding of the filaments, actin and myosin. The filaments begin to contract by using ATP.
During relaxation, the action potential is stopped. Calcium is taken back into the sarcoplasmic reticulum. As a result, actin and myosin filaments do not link and hence, the contraction is stopped.
The experts calculate that between 0.01 and 0.1% of all species will become extinct each year. If the low estimate of the number of species out there is true - i.e. that there are around 2 million different species on our planet - then that means between 200 and 2,000 extinctions occur every year.
What is extinction?
- Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species.
- The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence.
- More than 99% of all species that ever lived on Earth, amounting to over five billion species, are estimated to have died out.
- It is estimated that there are currently around 8.7 million species of eukaryote globally, and possibly many times more if microorganisms, like bacteria, are included. Notable extinct animal species include non-avian dinosaurs, saber-toothed cats, dodos, mammoths, ground sloths, thylacines, trilobites and golden toads.
- Through evolution, species arise through the process of speciation—where new varieties of organisms arise and thrive when they are able to find and exploit an ecological niche and species become extinct when they are no longer able to survive in changing conditions or against superior competition.
- The relationship between animals and their ecological niches has been firmly established.
- A typical species becomes extinct within 10 million years of its first appearance, although some species, called living fossils, survive with little to no morphological change for hundreds of millions of years.
To learn more about extinction: brainly.com/question/14482178
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The medulla oblongata detects the levels of oxygen and carbon dioxide concentrations and signals the muscles in the heart, the lungs and diaphragm to increase or decrease thebreathing. The pons controls the speed of inhalation and exhalation orrespiration rate depending on the need of the body.
There is one common fact that usually appears in option box and even though you didn't share any to choose the correct one, I think the information which I will give you will definitely help you. <span>All matter contains a vital force- this answer should coincide with those you were given. Hope you still need it because this one is really helpful.</span>
There’s one hundred centimeters in one meter, and one thousand millimeters per meter.
that being said, 3000 mm are in 1 meter
