The patellar reflex or knee(j)erk reflex doesn't happen when your leg is straight because the tendon is relaxed. In order for the reflex to be elicited, the tendon must be flexed or stretched.
Answer:
Artificial selection is the identification by humans of desirable traits in plants and animals, and the steps taken to enhance and perpetuate those traits in future generations. Artificial selection works the same way as natural selection, except that with natural selection it is nature, not human interference, that makes these decisions.
Explanation:
Answer and Explanation:
The process of transmission of heat due to the movement of molecules in the fluid is called convection. Convection also takes place on a global scale. At the equator, warm and less dense air tends to flow and rise towards the poles. Then denser, cooler air sinks and flow back towards the poles. Due to the rotation of earth rising warm air from the poles does not make it all the mode towards the pole. The combination of the earth’s rotation and global convection makes a series of wind patterns known as convection cells. The earth's rotation also alters the airflow pathway, which causes the wind’s path to be curved as it travels between the equator and poles. In the southern hemisphere, winds turn to the left and move anticlockwise around a high-pressure centre, while in the northern hemisphere, winds turn to the right and move clockwise around a high-pressure centre. The twisting of air currents, due to the rotation of the earth is termed as Coriolis effect. Due to this effect, winds turn to the left in the southern hemisphere. In the northern hemisphere, winds turn to the right.
