Answer:
Alpha-1
Explanation:
Adrenergic receptors are the integral proteins present in the postsynaptic plasma membranes. These receptors are activated when the neurotransmitter norepinephrine and the hormones norepinephrine and epinephrine bind to them. The alpha 1 adrenergic receptors are found in the smooth muscle fibers of blood vessels that serve the salivary glands, skin, and kidneys. These receptors are also found in the radial muscle of iris of the eye as well as in the sphincter muscles of the stomach and urinary bladder.
They exert excitatory effect and lead to contraction of smooth muscles of the blood vessels, dilation of pupil, and closure of sphincters of the bladder.
The continent of Africa is found mostly on the African Plate.
The best answer here is they show seasonal difference in flowering. if they self pollinated they could still interbreed assuming they flower in the same seasons
The question that Charles Darwin would be prompted to ask on his voyage is as follows: can selection in nature also lead to a new species over time?.
<h3>Who is Charles Darwin?</h3>
Charles Darwin was a British naturalist/scientist and founder of the theory of evolution by natural selection.
He is best known for his award-winning work on the origin of species, which he published in 1859. Darwin developed his theory from findings he made following a five-year expedition on board HMS Beagle.
According to this question, Darwin reviewed his observations after he returned home from his voyage studying the selective breeding of pigeons.
The question that Charles Darwin would be prompted to ask on his voyage is as follows: can selection in nature also lead to a new species over time?.
Learn more about Charles Darwin at: brainly.com/question/16489282
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