Question

Помогите решить задачу. Наблюдательный Алёша заметил, что некоторые растения, растущие в засушливых местах, густо покрыты ворсинками. Объясните, какое значение имеет эта особенность строения растений для их нормального существования.

Answer 1

По утрам на таких растениях образуются капельки росы а ворсинки мешают скатываться росе  с поверхности листа. За счет этой воды и происходит частичное питание растений в условиях недостатка влаги.

Answer 2

Importance of Trichomes for Plants in Arid Environments

The presence of dense trichomes (tiny hair-like structures) on the surface of plants growing in arid environments serves several important functions for their normal existence. These trichomes play a crucial role in the adaptation and survival of plants in dry conditions. Here are some key reasons why trichomes are significant for plants in arid areas:

1. Reducing Water Loss: Trichomes help reduce water loss from the plant's surface through a process called transpiration. Transpiration is the loss of water vapor from the plant's leaves and stems. The dense covering of trichomes creates a physical barrier that slows down the movement of air across the leaf surface, reducing the rate of transpiration. This adaptation helps plants conserve water and prevent dehydration in arid environments [[1]].

2. Reflecting Sunlight: Trichomes can reflect sunlight and reduce the amount of solar radiation absorbed by the plant's surface. By reflecting sunlight, trichomes help to lower the temperature of the plant's tissues, preventing overheating and reducing the risk of damage caused by excessive heat. This is particularly important in hot and dry environments where high temperatures can be detrimental to plant survival [[2]].

3. Providing Shade: The dense covering of trichomes creates a layer of shade over the plant's surface, reducing the intensity of direct sunlight reaching the underlying tissues. This shade helps to protect the plant from excessive solar radiation, which can cause damage to the photosynthetic machinery and other cellular components. By providing shade, trichomes help maintain the optimal temperature for plant growth and prevent sunburn [[3]].

4. Preventing Herbivory: Trichomes can act as a physical deterrent to herbivores, such as insects and grazing animals. The hair-like structures can make the plant's surface less palatable or more difficult to consume, reducing the likelihood of herbivory. Some trichomes may also produce chemical compounds that are toxic or repellent to herbivores, providing an additional defense mechanism for the plant [[4]].

In summary, the presence of dense trichomes on plants growing in arid environments is an important adaptation that helps them survive in challenging conditions. Trichomes reduce water loss, reflect sunlight, provide shade, and deter herbivory, all of which contribute to the plant's ability to thrive in arid habitats.