Descending tracts are the pathways by which motor
signals are pass through from the brain to lower motor neurones. Thus, all
the neurones within the descending motor system are classed as upper motor
neurones. The lower motor neurones then directly innervate muscles to produce
movement. Their cell bodies are found in the cerebral cortex or the brain stem,
with their axons remaining within the CNS.
Answer:
Another specialization of the skeletal muscle is the site where a motor neuron's terminal meets the muscle fiber—called the neuromuscular junction (NMJ). This is where the muscle fiber first responds to signaling by the motor neuron.
D. Neuromuscular Junction
Answer:
Pineal gland
Explanation:
The suprachiasmatic nucleus is the paired nucleus made of about 1000 neurons each in the hypothalamus. The suprachiasmatic nucleus is involved in maintaining the endogenous clock or the internal clock.
The suprachiasmatic nucleus controls the circadian rhythm by controlling the amount of melatonin. The melatonin is produced by the pineal gland from the serotonin and tryptophan precursors. The hypothalamus thus controls the amount of the melatonin by regulating the pineal gland.
Thus, Pineal gland is the correct answer.
Plants respire all the time, whether it is dark or light, because their cells need energy to stay alive. But they can only photosynthesize when they have light.
The oxidation of water occurs during photosynthetic electron transport during the light reactions of photosynthesis. In the absence of a source of light energy (dark reactions have no direct requirement for light energy), oxygen is not produced.
