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.
Answer:
Option A
Explanation:
Options -
A-avoid water pollution.
B-build thermal power plants.
C-add water features to gardens.
D-avoid drip irrigation systems
Solution -
The largest source of freshwater on planet earth is underground water. The water beneath the surface of earth is very limited. The total fresh water reserve on earth is 3% of the total water on earth. Pollution due to discharge of waste water into the rivers and oceans has caused the degradation of not only surface water but also ground water.
Thus, option A is correct
Drip irrigation is a means to prevent wastage of water during irrigation. Thus, avoiding it will cause further loss of fresh water.
Addition of water feature will increase usage of water, thus it is also incorrect
Building thermal plant will also cause water pollution and wastage. Hence, option B is also incorrect
<span>About 90% of the information you need to drive safely comes from your Eyes.
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<h2><u>Answer</u> :</h2>
The correct option is A. If a dominant allele is present, the recessive allele won’t be seen.
The dominant allele is the one which appear, and the recessive one isn't shown.
For example - If a person has 2 alleles of eye colour as B ( black ) and b ( brown ), in which black is dominant and the brown one is recessive, then the person will have black eye colour because only dominant allele shows its characteristics.
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