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.
2nd answer ecological succession .. don't know about the first one
Answer:
Enzyme
Explanation:
An enzyme is a type of catalyst, a substance that can increase the rate of chemical reactions without being consumed in the reaction. Catalysts are widely used in the industry because they produce products faster, thereby reducing costs.
To solve this problem we first need to find the amount of gametes a fruit fly produces in a meiotic division. For this we will use the formula 
, where n represents the number of gene pairs. In our case then, 
= 2.2.2.2 = 16
So a fly produces 16 different combinations of gametes. If this fly crosses another one, we have a universe of possibilities of combinations given by the multiplication of the male and female gametes. In the case, then, it would be 16 x 16.
16 x 16 = 256
Yes that is correct Force :D
