Answer:
The correct answer is A. dopamine.
Explanation:
Stimulants are believed to work by increasing dopamine levels in the brain. Dopamine is a neurotransmitter associated with motivation, pleasure, attention, and movement. For many people with ADHD, stimulant medications boost concentration and focus while reducing hyperactive and impulsive behaviors.
Answer:
Angiosperms
Explanation:
Angiosperms are important to humans in many ways, but the most significant role of angiosperms is as food. Wheat, rye, corn, and other grains are all harvested from flowering plants.
Answer:
Taking into account the concepts presented in chemistry with respect to elements and compounds, it is possible to affirm that the compounds are formed by two or more elements.
Explanation:
Two or more chemical elements have the ability to bind -by forming bonds- to obtain a compound. This occurs randomly in nature.
The bonds between the elements that form a compound must be stable enough to ensure the stability of the molecule. A chemical compound can only be separated into the elements that form it by chemical processes.
The bonds types that form compounds can be:
- <em>Ionic bond.</em>
- <em>Covalent bond.</em>
- <em>Coordinated covalent bond.</em>
- <em>Metallic bond.</em>
It is necessary to mention that chemical elements are called atoms, and the bonds between them are molecules. The physical and chemical properties of a compound will be different from the properties of the elements that form it.
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brainly.com/question/2835401
The answer is d. The population of light-colored moths decreased and the population of dark-colored moths increased.
<span>Peppered moth color variation is a good example of natural selection. During the Industrial revolution, due to pollution, trees become darker in the urban area. Light-colored moths were, thus, easy prey. The dark-colored moths were able to camouflage on dark trees and avoid predators. The phenomenon is known as industrial melanism. So, in polluted urban areas, the number of dark-colored peppered moths increased. In the clean environment, were much effective in hiding from predators and they outnumbered the dark-colored moths.</span>
Answer:
Colloids or colloidal solutions are mixtures in which microscopically dispersed insoluble particles of one substance are suspended in another substance. The size of the suspended particles in a colloid can range from 1 to 1000 nanometers (10-9 meters).
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