Urethra as Nephrons form Kidney and Urethra isn't a part of Kidney.
The three examples of stimulus include;
1. Hit the skin with a needle or pin is a good example of stimulus. The sudden removing of the hand is the response.
2. When somebody bangs a door you jump if you were unaware because of the sound. The jumping is the response to a stimulus.
3. Holding a hot plate we fling hand away from it. The stimulus here is holding the plate while removal of the hand is the response.
Stimulus is the change or cause in an organism's surrounding which causes the organisms to react.
<em>A megaphone used by a cheerleader can allow people on the opposite side of a field to hear her better because;</em>
D. Solid objects can change the direction of sound waves; megaphones allow users to determine the general direction of the sound.
<u>Determination of the general direction of the sound lessens its dispersion and thus, it reaches the observers at a higher intensity, hence it being louder.</u>
