<h2>Answer</h2>
The parasympathetic neurotransmitter at target organs is <u>acetylcholine</u><u>.</u>
<h3>#CarryOnLearning</h3>

Seeing as Peter is male, he's seeing a counselor (which indicates mental/emotional/psychological issues) and has been referred to a urologist, I'd say his problem is erectile dysfunction, or choice #2.
They both are encased organelle compartments inside a cell but A vacuole is the vesicle found within a cytoplasm of a cell. The vacuole contains some fluid. A lysosome, on the other hand, is an organelle found within the cytoplasm of eukaryotic cells.
Answer:
"Ecological niche is a term for the position of a species within an ecosystem, describing both the range of conditions necessary for persistence of the species, and its ecological role in the ecosystem."
Explanation:
sources: sciencedirect
What Mendel did according to the illustration would be called test-crossing.
<h3>Test-crossing</h3>
In genetics, test crossing is a procedure through which the zygosity of an individual can be determined - whether it is homzygous or heterozygous.
Test crossing requires that an organism who displays a dominant trait but whose zygosity is unknown is crossed with another organism of the same species but who displays the recessive version of the same trait.
By so doing and using the knowledge of probability, the resulting offspring from the cross will be used to determine the zygosity level of the parent.
More on test crossing can be found here: brainly.com/question/16805498