Answer:
The correct option is: <em>a deficiency of dopamine in the substantia nigra.</em>
Explanation:
The substantia nigra is the principal site involved in the physiopathology of Parkinson´s disease.
Cells from this area degenerate and die progressively causing important degeneration in the central nervous system. The cells that die -with no known reason- are those that produce dopamine and proportionate dopaminergic innervation to the encephalon. In fact, almost all the symptoms exhibited by patients with the disease can be explained by the lack of dopamine in the substantia nigra.
This area uses the neurotransmitter to communicate neurons from the base ganglia. Ganglia are responsible of modulating and modifying movements.
The nigrostriatal system participates in planning and automatic execution of learned movements. When the ganglia activity decreases, so it does the amount and velocity of movements, something typical of the disease.
<span>The organism will produce 12 chromosomes (A).
Sex cells are the products of meiosis. Daughter cells of meiosis contain half the number of chromosomes of the parent cell. So if the parent cell has 24 chromosomes, then the sex cell would have <em>12 chromosomes</em>.</span>
Answer:
The correct answer is ''carbon dioxide, water vapor and nitrogen.''
Explanation:
About 4.5 billion years ago, Earth was a very geologically active planet. So many volcanic fumes formed the primitive atmosphere, which was mostly made up of water vapor, carbon dioxide, sulfur, and nitrogen. At this point, oxygen was barely present and the oceans did not yet exist. The primitive atmosphere is the one before the Precambrian, it was reductive, that is, it lacked free oxygen, and only had ammonia, methane and hydrogen, the high temperature of the atmosphere in its early stages facilitated the reaction of these gases to form organic compounds from which life may have emerged. UV rays passed, because ozone did not exist.
Natural selection is a theory developed by Charles Darwin. It is believed that animal species evolve by nature "selecting" the ones that are fit to live in specific environments. For example, if an animal lacks a trait that is needed for a certain environment, it is likely to die. The animals that have the needed traits are more likely to live and procreate, which will pass on the trait to its offspring. Hope this helped!
Answer:
A. To gather and respond to information
Explanation: