The patellar reflex can be defined as the kicking movement of the lower leg which occurs with a sudden twitch when the patellar tendon of a person is tapped. This patellar tendon is present below a person's kneecap. This reflex happens only when the leg is bended. It is impossible for patellar reflex to occur if the leg is straight as the quadriceps muscles are already contracted and a sudden kicking movement of the leg in such state could not be elicited. The patellar reflex protects the quadriceps from stretching too much.
Answer:
Something studied on the molecular level is the water.
Explanation:
Water is a molecule formed by two hydrogen atoms and one oxygen atom, whose chemical representation is H₂O. It is a molecule whose polarity makes it a universal solvent of other polar molecules.
The molecular level corresponds to the level of organization where two or more atoms unite to form molecules or substances, united by chemical bonds. H₂O is studied at this level due to its chemical structure.
With respect to other options:
- <u><em>Hydrogen and oxygen</em></u><em> are atoms, and correspond to the level of atomic organization.</em>
- <u><em>Protons</em></u><em> are particles that are part of an atom, and correspond to the subatomic level.</em>
The stamen is the part of the flower that produces pollen.