Answer:
a. hox genes.
Explanation:
HOX genes have the following functions:
- HOX genes are the homeobox subset.
- They specify the areas of the embryo's body plan along the animal head-tail axis.
- They are encoding Hox proteins that specify the position characteristics and ensure that the right structures form at the right position in the body.
- They regulate high-level executive genes, such as transcription factors and intracellular signaling molecules, which adhere, number, form, and growth to cells.
The vertebrates are highly preserved.
The clusters and other genes occur uninterrupted.
Evolutionary, the heterogeneous regulatory areas between the genes most previously present are larger and more preserved than those present at the other ends of the clusters.
The characteristical feature is that these are homeodomain proteins with a highly preserved area of DNA binding encoded with homeobox gens.
Parkinson’s disease is triggered by degeneration of dopamine-producing neurons in the brain. <span> <span><span> <span> Parkinson's disease is a neurodegenerative disease of the CNS resulting from degeneration of dopamine-producing neurons in a region of the midbrain called the substantia nigra. Some of the factors that induce this disease are oxidative stress<span>, inflammation, and dysfunctional mitochondria. The disease is progressive including characteristic symptoms such as tremors, muscle rigidity, loss of coordination bradykinesia (slowness and difficulty with movements), sleep disturbances...</span> </span> </span> </span></span>
The eggs of the fluke are passed into water supplies from feces and urine of infected people. After hatching the parasite actively swims and invades the body of a snail, usually by penetrating through the snail's foot. The parasite requires the presence of certain species of snails (e.g., Oncomelania, Biomphalaria, Bulinus) to transform (and multiply) itself into an infective stage, called cercaria.
Ocean currents can be generated by wind so I believe the answer is B
