The Role of Auxin in Plant Growth

The video explains the role of auxin, a versatile biochemical, in plant growth and development. Auxin stimulates cellular elongation in roots and stems, leading to primary growth, and promotes cell division in cambium layers for secondary growth. It also influences flower and fruit development and is crucial for plant responses to gravity and light. Auxin produced in the stem tip inhibits lower branch growth, a phenomenon known as apical dominance. Removing the stem tip allows lateral growth, a technique used by gardeners for shaping plants.

What is the primary role of auxin in plant growth?

• Inhibiting cellular elongation in roots and stems

• Reducing flower growth

• Stimulating cellular elongation in roots and stems

• Promoting leaf fall

How does auxin affect the growth of flower parts?

• It has no effect

• It causes them to wilt

• It stimulates their growth

• It inhibits their growth

What is the term for the plant behavior where the central stem tip's growth is prioritized over side branches?

• Root dominance

• Apical dominance

• Lateral dominance

• Stem suppression

What happens when the central stem tip is removed?

• The plant dies

• Lower lateral stems and buds develop normally

• The main stem grows faster

• The plant stops growing

Why do gardeners prune the tips of stems and branches?

• To stop the plant from growing

• To create plants with interesting shapes

• To reduce the number of flowers

• To promote the growth of the main stem