Two terms for the massive motor tracts serving voluntary movement are two terms for the massive motor tracts serving voluntary movement are pyramidal and corticospinal extrapyramidal and rubrospinal supplementary and cerebellar-pontine segmental and nigrostriatal

pyramidal and corticospinal

Explanation:

Motor pathways control body posture, reflexes and muscle tone, as well as conscious conscious movements. The best known motor route is the pira pyramid system ', which begins in the large pyramidal neurons of the motor cortex, continues along the pyramids of the brain stem and ends at or near the alpha motor neurons. This motor system is extraordinarily important in the clinic, because it is frequently affected by vascular accidents of the brain.

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.