IAA and Plant Growth Responses

The video tutorial by Miss Estrich covers plant growth factors, focusing on IAA and tropisms. It explains how plants respond to stimuli like light and gravity through phototropism and gravitropism. The role of IAA, a type of auxin, in cell elongation and growth inhibition is discussed, highlighting its effects in shoots and roots. The tutorial also differentiates between positive and negative tropisms and provides insights into plant responses at the A-level compared to GCSE.

What is the main focus of the video tutorial?

• Animal growth factors

• Plant growth factors, specifically IAA and tropisms

• Human anatomy

• Cellular respiration

What term describes a plant's growth response towards a stimulus?

• Respiration

• Tropism

• Metabolism

• Photosynthesis

Which of the following is NOT a key stimulus for tropisms?

• Sound

• Water

• Light

• Gravity

What is IAA and how does it function in plants?

• A type of hormone that circulates in plant blood

• A plant growth factor that influences cell elongation

• A mineral absorbed by plant roots

• A pigment responsible for photosynthesis

Where is IAA produced in plants?

• In the flowers

• In the tip of the roots and shoots

• In the leaves

• In the stem

What happens to a plant when light is evenly distributed?

• IAA causes the plant to stop growing

• IAA causes the plant to grow downwards

• IAA causes the plant to grow upwards

• IAA causes the plant to grow sideways

How does IAA affect root growth in response to light?

• It causes roots to grow towards the light

• It inhibits cell elongation on the shaded side

• It promotes cell elongation on the shaded side

• It has no effect on root growth

What is the effect of IAA on shoots in response to gravity?

• IAA causes shoots to grow upwards

• IAA causes shoots to grow sideways

• IAA has no effect on shoots

• IAA causes shoots to grow downwards

In gravitropism, how does IAA affect root growth?

• IAA causes roots to grow away from gravity

• IAA has no effect on root growth

• IAA causes roots to grow towards gravity

• IAA causes roots to grow upwards

What is the term for a plant's growth response towards gravity?

• Gravitropism

• Hydrotropism

• Phototropism

• Thigmotropism