Obtain the observation report of the phototropism experiment of the observation plant

Experimental steps: 1. Mark the opaque cartons as No. 1, No. 2, No. 3 and No. 4 respectively;

2. Use scissors to dig a hole with a diameter of 1 cm on the side of the opaque carton, which is used when simulating one-sided lighting and filial piety;

3. The opening position is No. 1 transmittance hole on the left side, No. 2 transmittance hole on the right side, No. 3 transmittance hole in the front, and No. 4 transmittance hole in the top Qiaochen part;

4. Buckle the prepared light shield to the flower pot, place the device in a sunny place during the day, replace the light source with a table lamp at night, and let the light penetrate into the carton from the small hole;

5. After two weeks, observe the hidden growth of the seedlings.

The survival of the eight organisms depends on a certain environment (the influence of light on the distribution, growth and reproduction of plants).

a. The independent variable of the experiment is whether there is light or not, which can prove the effect of light on plants, and a is wrong;

b. The analysis of the problem diagram shows whether the independent variable has one-sided light conditions, so it can be proved that the plant growth is phototropic, and b is false;

c. It can be proved that the roots of the plant have gravity, and the stems of the plant can also be proved to be back-to-the ground, c is false;

d. As can be seen from the title diagram, the aboveground part is not treated, and the purpose is to form a comparison with the experiment, and D is correct

Therefore, d

In biology lessons, it is mentioned that many plants are phototropic, but are all plants phototropic? This non-stop long-term time-lapse of the plant shows how the plants react in the sun during the day and night. Do you think it's phototropic?

Check out "Darwin's Study on the Phototropism of Canary Crane Grass Germ Sheaths".

It's not that you don't want sub-research, but you want results? Then I'm talking about the fastest way, although it's not quite in line with the idea of scientific research...

9:00 the next day

The temperature is slightly slightly weathered.

The seedlings of a group of translucent cartons are at an angle of 5 degrees to the wooden sticks, and the seedlings of the opaque carton grow straight upwards on the third day.

The temperature is slightly slightly weathered.

The seedlings of a group of translucent cartons are at an angle of 10 degrees with the wooden sticks, and the seedlings of the opaque carton grow straight upwards on the first day.

The temperature is slightly slightly weathered.

The seedlings of a group of translucent cartons are at an angle of 18 degrees to the wooden sticks, and the seedlings of the opaque carton grow straight to the four on the fifth day.

The temperature is slightly slightly weathered.

The seedlings of a group of translucent cartons are at an angle of 25 degrees with wooden sticks, and the seedlings of opaque cartons grow straight upwards for group A.

Group B Day 1.

There is no obvious tendency to grow in the direction of growth.

There is no obvious tendency to grow in the direction of growth.

There is no obvious tendency to grow in the morning.

There is no obvious tendency to grow in the direction of growth.

Noon on the first day.

There is no obvious tendency to grow in the direction of growth.

There is no obvious tendency to grow in the direction of growth.

First night.

There is no obvious tendency to grow in the direction of growth.

There is no obvious tendency to grow in the direction of growth.

Two days later in the morning.

There is no obvious tendency to grow in the direction of growth.

There is a tendency to grow in a more obvious direction.

in the direction of the window) three days later in the morning.

There is no obvious tendency to grow in the direction of growth.

There is a tendency to grow in a more obvious direction.

in the direction of the window) four days later in the morning.

There is no obvious tendency to grow in the direction of growth.

There is a tendency to grow in a more obvious direction.

to the window).

Aqueous experimental scheme for plant roots: take 5 Petri dishes, No. 12345, five soybean or corn seeds, some sponges and foam, and cut the sponges and foam into semi-circles, just enough to fit into the Petri dish. Put a sponge in the 1234 petri dish (the sponge is in four different directions), a piece of foam, a seed in the middle, put two sponges in the No. 5 and a seed, only water the sponge in No. 1234, keep the sponge moist, but not make the petri dish water, the same is true for No. 5, and then put it at a suitable temperature to cultivate, after the seeds grow roots, observe the length of the roots from the bottom of the petri dish.

The photosensitive part of the plant is to feel the light, which affects the distribution of auxin, and the auxin is transported laterally, and there is less auxin on the light-facing side and more on the backlight side, so the backlight-side grows fast and bends towards the light.

Whether the plant is curved or not depends on whether auxin is evenly distributed. When analyzing the experimental settings such as light, the presence or absence of photosensitive parts, and the placement of agar blocks with auxin, as long as the auxin distribution is uniform, it does not bend, and if it is uneven, it bends to the side with less auxin.

Remove the germ sheath at the tip, place the agar block with auxin, and then irradiate the light source under the problem: if the agar block is on the entire section, then the auxin is uniform, growing but not bending; If placed on one side, bend toward the side without agar blocks.

Yes, because plants have phototaxis.

Bending towards the light is just because the auxin is not evenly distributed, and it's good to keep that in mind.