Biology Revision - Nerves And Hormones - Plant Hormones

Auxin is a plant hormone that plays a crucial role in controlling the growth of plants, particularly in the tips of shoots and roots. It regulates various processes such as cell elongation, root development, and the formation of lateral roots. Auxin also influences phototropism, gravitropism, and apical dominance. By promoting cell division and elongation, auxin helps in the overall growth and development of plants. Additionally, it is involved in tropic responses, directing plant growth towards or away from stimuli such as light and gravity.

Plants exhibit a behavior called phototropism, where they grow towards a light source. In this scenario, if the plant is placed on its side in a pot, it will still grow towards the light. As it starts to grow, the stem will bend and curve in the shape of a 'J' as it tries to reach the light source. This is because plants need light for photosynthesis, which is essential for their growth and survival.

When the auxin is transported to the bottom of the root due to its flat sideways growth, it creates a high concentration of auxin in that area. This high concentration of auxin inhibits the growth of cells, resulting in less elongation. As a result, the root is directed to grow down towards gravity.

Auxin is a hormone that is involved in plant growth and development. It is known to be transported from the tip of a plant towards the side where light is shining. This movement of auxin allows the plant to respond to light and regulate its growth accordingly.

The roots of the sideways plant would bend and grow down in response to gravity. Gravity is a force that pulls objects towards the center of the Earth, and plants have evolved to respond to this force by growing their roots downwards. This allows the roots to anchor the plant in the soil and absorb water and nutrients from the ground.

Roots have a natural tendency to grow downwards due to gravity, which is known as positive geotropism. This allows them to anchor the plant in the soil and seek out sources of moisture. Geotropism is a plant's response to gravity, where roots grow in the direction of the gravitational force, while shoots grow in the opposite direction (negative geotropism). This adaptive behavior ensures that roots can access water and nutrients from the soil, promoting the overall growth and survival of the plant.

When a shoot grows upwards and towards the light, it is exhibiting positive phototropism. Phototropism is a plant's response to light, where it grows towards the light source. This is due to the plant hormone auxin, which moves towards the shaded side of the plant and causes elongation of cells, resulting in bending towards the light. Positive phototropism allows plants to maximize their exposure to sunlight, which is essential for photosynthesis and overall growth and development.

Plants have a natural response called phototropism, where they grow towards a light source. This is because plants need light for photosynthesis, the process by which they convert light energy into chemical energy to fuel their growth. By growing towards the light, plants can maximize their exposure to sunlight and ensure they have enough energy to survive and thrive.

Plants exhibit a phenomenon called gravitropism, which is the growth response of plant organs towards or away from gravity. Shoots grow away from gravity, meaning that they exhibit negative gravitropism. This allows the shoots to grow upwards towards the sky, where they can receive more light for photosynthesis. Light is an essential factor for plant growth, but in this case, gravity is the determining factor for the direction of shoot growth. Moisture, on the other hand, does not play a direct role in shoot growth direction.

As the auxin moves down the shoot, it causes cell elongation. A greater concentration of auxin on one side causes more cell elongation on that side, which causes the shoot to elongate towards the light.

Auxin is a plant hormone that plays a crucial role in regulating plant growth and development. In the context of the question, when there is an excess amount of auxin (extra auxin), it inhibits growth. This is because auxin controls cell elongation and division, and an excessive amount can disrupt the balance of growth factors, leading to the inhibition of growth.

When light shines from one side, the hormone auxin is transported away from the light at the tip. This is because auxin is known to move away from the light source, causing the plant to grow towards the light. This phenomenon is called phototropism, where the plant bends towards the light in order to maximize its exposure to sunlight for photosynthesis. Therefore, the correct answer is "away".

Geotropism is the growth or movement of a plant in response to gravity. When a shoot grows away from gravity, it is exhibiting negative geotropism. This means that the shoot is growing in an upward direction, against the force of gravity. Geotropism plays an important role in plant growth and development, as it helps the plant orient itself properly in relation to gravity and optimize its exposure to light and nutrients.

When a root grows flat sideways, the auxin hormone is transported to the bottom of the root. This causes a high concentration of auxin in that area. The high concentration of auxin inhibits growth, meaning that there are fewer cell divisions and less cell elongation. As a result, the root is able to grow down towards gravity.

they can be and are used for farming

Rooting powder contains auxin, a plant hormone that promotes root growth. When applied to the end of a cutting, auxin stimulates the development of new roots. This helps the cutting establish itself as a new plant. Therefore, the statement that rooting powder contains auxin to encourage new root growth is true.

Weedkillers contain rapid growth hormones which disrupts normal growth patterns and they can use up their food reserves and die.

Roots grow towards gravity because gravity helps them in anchoring the plant firmly in the ground. The force of gravity pulls the roots downwards, allowing them to penetrate the soil and provide stability to the plant. Additionally, roots also grow towards moisture as they need water for their survival. They have the ability to sense the presence of moisture in the soil and grow towards it in order to absorb water and nutrients essential for the plant's growth and development.