The growth of pollen tube towards the ovule is due toa)Hydrotropismb)Chemotropismc)Geotropismd)PhototropismCorrect answer is option 'B'. Can you explain this answer?

Question

Answer

The movement of a plant part in response to a chemical is called chemotropism. If  the plant part shows movement towards the chemical it is called positive chemotropism . On the other hand if the plant part shows movement away from the chemical then it is called negative chemotropism. The growth of pollen tube towards the oval during the process of fertilization in a flower is an example of chemotropism. In this case the pollen tube growth towards the substance secreted by ripe  stigma of carpel in the flower.

Answer

Chemotropism is the growth or movement of a plant or plant part in response to a chemical stimulus. An example is the growth of a pollen tube down the style during fertilization in response to the presence of sugars in the style. Hence option(b) is the correct answer.

Answer

Chemotropism is defined as the growth of organisms navigated by chemical stimulus from outside of the organism. It has been observed in bacteria, plants and fungi. A chemical gradient can influence the growth of the organism in a positive or negative way.

Answer

Answer b) Chemotropism
as chemotrpism means growth of plant towards the chemical stimulus. The growth of pollen tube
towards the ovule is an example of chemotropism.

Answer

Yeah its option b bcz chemotropism is growth of plant part in response to chemical stimulus

Answer

The correct answer is option 'B' - Chemotropism.

Explanation:
Pollen tubes are an important part of the process of fertilization in plants. They are responsible for delivering the male gametes (sperm cells) from the pollen grain to the ovule for fertilization to occur. The growth of pollen tubes towards the ovule is a complex process that involves various factors, including guidance by chemical signals released by the ovule.

Chemotropism, also known as chemotaxis, is the movement or growth of an organism or cell towards or away from a chemical stimulus. In the case of pollen tubes, they exhibit positive chemotropism, meaning they are attracted towards certain chemicals released by the ovule.

Here is a detailed explanation of how chemotropism plays a role in the growth of pollen tubes towards the ovule:

1. Pollination:
Pollination occurs when pollen grains are transferred from the anther (male reproductive structure) to the stigma (female reproductive structure) of a flower. This can happen through various means, such as wind, water, or pollinators like insects or birds.

2. Pollen Germination:
Once a pollen grain lands on the stigma, it germinates and begins to grow a pollen tube. The pollen tube is a long, tube-like structure that extends from the stigma towards the ovule.

3. Chemical Signals:
As the pollen tube grows, it is guided by chemical signals released by the ovule. The ovule produces various chemicals, including sugars, amino acids, and hormones, which act as attractants for the pollen tube.

4. Reception and Response:
The pollen tube has receptors on its surface that can detect and respond to these chemical signals. When the tube senses the presence of the chemicals, it grows towards the source of the signals.

5. Directional Growth:
The chemical signals create a gradient, with higher concentrations nearer to the ovule. This concentration gradient acts as a directional cue for the pollen tube, causing it to grow in the direction of the highest concentration of the chemicals.

6. Penetration of the Ovule:
The pollen tube continues to grow and elongate, guided by the chemical signals, until it reaches the ovule. Once the tube reaches the ovule, it penetrates through one of the micropyles (small openings) in the ovule's protective layers.

7. Fertilization:
After the pollen tube enters the ovule, it releases the sperm cells, which then fuse with the egg cell and central cell inside the ovule, resulting in fertilization and the formation of a zygote and endosperm.

In conclusion, the growth of pollen tubes towards the ovule is primarily due to chemotropism. The chemical signals released by the ovule attract the pollen tube and guide its growth towards the ovule for successful fertilization to occur.

Similar Class 10 Doubts

The growth of pollen tubes towards ovules is due to

The Growth Of Pollen Tubes Towards Ovules Is Due To

In flowering plants the growth of the pollen tube toward ovules is an example of

Match the following-Column I Column II1. Hormones i) Shoot2. Seedling germination ii) growth of pollen tubes towards ovules3. Chemotropic iii) Root4. Positively geotropic iv) synthesized at places away from where they act5. Positively phototropic v) growth

The movement of shoot towards light is

Top Courses for Class 10View all

Science Class 10

Social Studies (SST) Class 10

Mathematics (Maths) Class 10

English Grammar Advanced

English Grammar Basic

Top Courses for Class 10

Top Courses for Class 10

Suggested Free Tests

Related Content

About Class 10

Class 10 Study Material

Class 10 All Subjects

NCERT Textbook Solutions

Other Classes

Important Links

Company