Answer:
By action potential nerve contract the muscle
Explanation:
The muscle contract when the nervous system sends action potential to the muscle. So the nervous system delivers signal to muscle, the first signal reaches the neuromuscular junction. The signals are passed by a chemical messenger called neurotransmitter release by motor neurons, the chemicals bring reaction and shorten the muscle fibre. When neurotransmitter are absent or reduce in concentration the process reverse and muscle relax again.
I believe the correct answer is natural selection.
Natural competition and the fight for “survival of the fittest” is what pushes diversity the most.
Answer:
well were not running out but not every place has clean water and no we never run out of clean water. theres always clean water
Explanation:
Answer:
The answer is 50
Explanation:
Hemophilia is a X-linked disease. That means the recesive allele which causes the disease is not in Y chromosome, but only in X chromosome. If we denote:
X⁺ : dominant allele
X⁻: recesive allele
Then, in a woman there are three posibilities:
X⁺X⁻: is a carrier woman (without hemophilia)
X⁺X⁺: healthy woman
X⁻X⁻: woman with hemophilia
But in a man there are two posibilities:
X⁺Y: healthy man
X⁻Y: man with hemophilia
A man with hemophilia is X⁻Y, and a healthy woman whose mother had hemophilia is a carrier woman (X⁺X⁻). If they have a child, there are 4 posibilities, and each one has 1/4 of occurrence probability:
X⁻Y x X⁺X⁻ = X⁻X⁺, X⁻X⁻, X⁺Y, YX⁻
Posibilities with hemophilia are X⁻X⁻ and YX⁻ (1/4 + 1/4= 1/2= 0.5= 50%)
In each filial, there is a 50 percent of probability of having a child (man or woman) with hemophilia.
