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:
Essentially there is not an answer. There are two different definitions.
A holoenzyme is an enzyme that needs to be together with a cofactor(s), required for activity.
In some cases, enzymes constituted by several subunits (like DNA polymerase 3) are call holoenzyme as well, because it will only perform correctly when all its subunits are present.
Answer: Minerals
Explanation: The body decomposes and after about 40 to 50 years bones are mostly brittle and dry with no traces of flesh. After thousands of years bones also disintegrate (decay) leaving brittle mineral frame. The life of bones is determined by the soil type its buried in, nuetral soils takes longer then acidic soil condition.
In this case osteocytes(bone cells) are the first to decompose followed by the cartilage and bone marrow, leaving behind mineral traces that scientist can study after thousand years.
A. Looks like the mesophyll of a leaf or a section of it
B. Is the stem
C. Is the surface of the leaf
(I don’t really have any vocab so I can get an exact answer)
The answer is true because A and G always go together