THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -The roots grown downward in the direction of gravity, which is positive gravitropism, and the shoot grows upward away from gravity, which is negative gravitropism. The reason plants know which way to grow in response to gravity is due to amyloplasts in the plants.

Detailed explanation-2: -Plants have the ability to sense a change in the direction of gravity, which leads to the re-orientation of their growth direction, so-called gravitropism. In general, plant stems grow upward (negative gravitropism), whereas roots grow downward (positive gravitropism).

Detailed explanation-3: -Charles Darwin was one of the first to scientifically document that roots show positive gravitropism and stems show negative gravitropism. That is, roots grow in the direction of gravitational pull (i.e., downward) and stems grow in the opposite direction (i.e., upwards).

Detailed explanation-4: -Positive geotropism refers to the downward growth of plants, going with the force of gravity. Positive geotropism is seen in the roots of plants because the roots of plants grow downward with the force of gravity.