Answer:
a. substantia nigra
b. substantia nigra (it is repeated)
Explanation:
Parkinson's disease is a neurodegenerative disease that is caused by the death of neurons that release the neurotransmitter dopamine in the <u>substantia nigra</u>, or locus niger, -a region of the brain that regulates brain circuits that give the 'orders' to initiate voluntary movements- .
The lack of this neurotransmitter leads to the occurrence of the main symptoms suffered by patients: decreased movements, muscle stiffness, postural instability and tremor. These failures are generated by the abnormal way in which neurons work in the absence of dopamine through a mechanism that is not known in depth.
It is the second most frequent neurodegenerative disease, after Alzheimer's disease, with a prevalence of 2% in people over 65 years. The characteristic symptoms of stiffness, bradykinesia and tremor are associated with losses of neurons in the substantia nigra and dopamine depletion in the striatum. There are large cytoplasmic inclusions, called Lewy bodies, which are the pathological mark of the disease and appear predominantly in neurons that contain melanin of the nigra substance. Genetic studies in a subgroup of families with Parkinson's disease with autosomal dominant inheritance found a locus on chromosome 4q-21 23 and a mutation in the gene that encodes a synaptic protein, α-synuclein.
Answer:
Saturation
Explanation:
A solution with as much dissolved solute as it can hold at a given temperature is said to be saturated. The solution is homogeneous since the solute and solvent are evenly distributed in the solution. The solution is saturated however, since no more solute can dissolve at a given temperature.
a. parsimony; simplest; fewest
When selecting among multiple possible phylogenetic trees that fit our data, we commonly use the principle of <u>parsimony</u>, which means we choose the <u>simplest</u> possible hypothesis. In phylogenetic analysis, that means selecting the tree that represents the <u>fewest</u> evolutionary changes or mutations.
Explanation:
Phylogeny describes the evolutionary history of on organism or group of organisms.
A phylogenetic tree structure is used to describe the relationship between various organisms which have originated from common ancestors.
The Principle of Parsimony is best applied while constructing phylogenetic tree.
This principle emphasizes on simple observations on a phylogeny which requires only few changes or variations which explain for the difference between the phylogenic sequences.
This tree structure will only have few specific genetic variations or mutations or evolutionary changes which took place through new appearance of a trait or disappearance of an existing trait.
Helicase "unzips" the two strands of DNA. During DNA replication.
I would choose the option D.
D. It remains tightly coiled at the G1 phase.
