What are two additional characteristics of the phototropism response?
describeTWO additional characteristics of the phototropism response. Description (2 points maximum) • Tip produces a substance/signal/hormone (auxin) in response to light causing the plants to bend • Substance must diffuse from the tip causing the plants to bend ©2015 The College Board.
Why did the plant in treatment group III not bend toward light?
The response earned 1 point for supporting the claim by saying that the plant in treatment group III did not bend toward the light because the tip is covered, so it is not exposed to light. The response earned 1 point in part (b) for describing that the tip sends the signal to the rest of the plant.
How many different experimental treatments have been used to study phototropism?
five different experimental treatments from classic investigations of phototropism are shown above. (a)Give supportfor the claim that the cells located in the tip of the plant shoot detect the light by comparing the results from treatment group I with the results from treatment group II and treatment group III.
Why do shoots grow straight up rather than toward the light?
The response earned 1 point in part (a) for supporting the claim by saying that cells in the shoots with the tip removed cannot detect light so the shoots grow straight up rather than toward the light.
Which plant hormone causes bend of shoot towards light?
auxinauxin distributions are responsible for phototropic responses—i.e., the growth of plant parts such as shoot tips and leaves toward light. In certain cases auxin may be destroyed on the illuminated side, and the unilluminated side with more auxin elongates, causing the shoot to bend toward the light.
What is the stimulus that made the shoot bend towards the window?
Answer. An auxin, is a plant growth hormone that helps regulate shoot growth. ... But when sunlight varies, auxin is broken down on the sunnier side of the stem. The higher concentration of auxin on the shady side causes the plant cells on that side to grow more so it bends toward the light.
What is the phenomenon that is causing shoot of the bean seedling to bend towards the light?
Phototropism is a directional response that allows plants to grow towards, or in some cases away from, a source of light.
What's it called when a plant grows toward light?
"Even mature plants bend toward the strongest light. They do this by elongating the cells of the stem on the side that is farthest from the light. This type of light-oriented growth is called phototropism," explains Prof.
When a plant bends toward the light the bending is an example of which characteristic of life?
Phototropism. You might have noticed that plants bend toward the light. This is an example of a tropism where light is the stimulus, known as phototropism (Figure below). To obtain more light for photosynthesis, leaves and stems grow toward the light.
What caused the shoots of the seedlings on the windowsill to bend towards the window?
The plants lean because of a phenomenon called differential growth, where the cells on the “dim” side of the stem grow faster than the cells on the “bright” side. The result is that the plant bends toward the light source.
What causes a plant to bend toward light?
When light comes from an angle, plants will curve toward it to get better access to the light they need to grow. Hormones in the plant's tissues, called auxins, make cells on the dark side of the plant grow taller, bending the plant toward the light.
What is the phenomenon that is affecting the growth of the bean shoot?
What is the phenomenon that is affecting the growth of the bean shoot in Figure 24-3? thigmotropism.
How can bending a plant stem affect the plants ability to grow?
It does not affect the ability of plant to grow. The stems grow towards the light source. So, even if the stem is bent, it will continue growing towards the light source.
How do auxins cause plant shoots to grow towards light quizlet?
the shoot bends so that i grows towards the light. Auxin moves to the unlit ( dark) side of the shoot causing the cells on that side to grow more ( respond to the hormone). Shoot bends towards he light.
What vernalization means?
Definition of vernalization : the act or process of hastening the flowering and fruiting of plants by treating seeds, bulbs, or seedlings so as to induce a shortening of the vegetative period.
How does auxin help in the bending of shoot towards the light source?
(a) When light is coming from one direction of plant, auxin synthesised at the shoot diffuses towards shady side. This concentration of auxin stimulates the cells to grow longer on the side of the shoot which is away from light. Thus plant appears to bend towards light.