NEET BIOLOGY

Detailed explanation-1: -Positive gravitropism occurs when roots grow into soil because they grow in the direction of gravity while negative gravitropism occurs when shoots grow up toward sunlight in the opposite direction of gravity.

Detailed explanation-2: -Plant parts can grow with or against gravity. This type of tropism is called gravitropism. Roots of a plant grow downward and exhibit positive gravitropism. Stems, on the other hand, exhibit negative gravitropism since they grow upwards and against the force of gravity (see Figure 1).

Detailed explanation-3: -When a root grows in the direction of the force of gravity (downwards), this is known as a positive gravitropism.

Detailed explanation-4: -The positive gravitropic response occurs in the belowground root system, which re-orientates the root-tip growth angle toward the GSA and allows the roots to penetrate deep into the soil to anchor the plant and uptake nutrients and water.

Detailed explanation-5: -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).