Hormones are the intercellular signal discharged into the blood by specific cells, they travel some distance in order to reach their target tissues and to perform other specific activities. Autocrine refers to the intercellular signals, which are discharged by the cells in a local area and affects the activity of the similar type of cell from which it was discharged.
Paracrine refers to the intercellular signals, which are discharged by the cells and influences other kinds of cells locally without being transported into the blood. Pheromones refer to the intercellular signals secreted into the surrounding and change the behavior and physiology of other individuals.
Neurohormones or neurotransmitters are the intercellular signals produced by the neurons. Of the mentioned intercellular signals, the "e" signifies neurotransmitter.
Answer:
e) directional selection
Explanation:
Directional Selection:
- The type of natural selection that favors one of the extremes of the phenotype spectrum, shifting the allele frequency to one direction
- This type of selection selects against intermediate and one of the extreme phenotypes.
- In this particular case, the increasing pollution has pushed the plants to evolve better acid tolerance.
- This indicates that if the environmental conditions worsen, only the acid tolerant plants will be able to survive.
* Another example is illustrated in the image. The graph shows the shifts in allele frequency.
Yes, because there is only so much weight it can hold.
C) one that must be imported to the U.S.
A bond formed by the electrical attraction between two oppositely charged ions is a(n) ionic bond.
