How does the stretch reflex cause the quadriceps femoris muscle group contract?

Need an answer asap 45 points and brainlest to the first person to answer why do scientific theories, such as biological and chemical evolution, represent the strongest explanation of the changes observed in the fossil record. must be in sentence form how can scientific theories on evolution and the fossil record change over time? must be in sentence form

Which is a kingdom? protistachordataprokarya mammalia

Why are some people more concerned about shark survival than about shark attacks?