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.
Survivorship curve = so, first of all, it's a curve, as in a graph.
It describes "survivorship" - the rate of survival, in other words: out of 100 organisms that are born, how many survive. This rate is different among species, for example, most humans live out to most of their life span, and almost all can survive well beyond a reproductive age.
However, in frogs for example, many many individuals are born, but only few can survive to adulthood: most die very young, before reproductive age.
So if you hear about a new species: let's say dogs, and you want to know how long they would live, you would look at their sirvivorship curve (and in some breeds of dogs, those that are likely not to be in shelters, but in homes, the survivorship curve would be similar as in humans: almost all individuals born can live long.
Random changes in allele frequency in a population are usually called genetic drift. The reason why this is the answer is because it is a very specific word which is used to describe exactly that - random changes in allele frequency.
All the other cases; answers, here aren't correct and don't apply.
<span>b.Eusthenpteron might be a common ancestor of bats and humans.
Hope this helps!
-Payshence xoxo</span>
Answer:
B
Explanation:
It represents the greatest amount of cell differentiation for the newly formed organism.
Here all the organs and system get initiation and cell differentiate to form various organs.
