<span>In the "all or none" law of muscle contraction, it states that when the stimulus applied exceeds threshold then the the nerve sending signals to a few muscle fibers will give a complete response; contraction. Graded response is dependent on how many motor units have been recruited. The more motor units, the greater the force in the contraction.</span>
Yes you are right I think
Answer: Photoperiod controls many developmental responses in animals, plants and even fungi These mechanisms include the detection of the light signal in the leaves, the entrainment of circadian rhythms, and the production of a mobile signal which is transmitted throughout the plant.
Answer:
it looks like a villi to me
