Test: Transportation in Plants - Class 8 MCQ

Transpiration cools the plant by evaporating water from its surface, which requires energy and helps lower the plant's temperature. This cooling effect is especially beneficial during hot weather, helping maintain optimal growth conditions.

Root hairs increase the surface area available for absorption, which enhances the plant's ability to take in water and dissolved minerals from the soil. This increased surface area is crucial for efficient nutrient uptake.

Higher temperatures increase the rate of transpiration as they enhance the evaporation of water from leaf surfaces. This can lead to increased water and nutrient movement through the plant, but also requires adequate water supply.

Xylem is responsible for transporting water and dissolved minerals from the roots to other parts of the plant, primarily the leaves. This movement is crucial for maintaining hydration and nutrient supply, which supports overall plant health.

Transpiration is the process by which water vapor is lost from the plant, primarily through tiny openings called stomata on the leaves. This process not only helps with cooling the plant but also aids in nutrient transport.

The "ascent of sap" refers to the upward movement of water and minerals through the xylem vessels from the roots to the leaves. This process is essential for maintaining plant hydration and facilitating nutrient transport.

During absorption, roots take in water and minerals from the soil through specialized structures like root hairs. This process is vital for supplying the plant with necessary nutrients for growth and development.

High humidity slows down transpiration because the air is already saturated with moisture, making it difficult for additional water vapor to escape from the plant's stomata. This can impact the plant's ability to cool itself and transport nutrients effectively.

Magnesium is a crucial mineral for photosynthesis because it is a central component of chlorophyll, the pigment responsible for capturing light energy. Without adequate magnesium, plants would struggle to perform photosynthesis effectively.

Osmosis is the movement of water molecules across a semi-permeable membrane from a region of higher water concentration to a region of lower water concentration. This process is vital for maintaining cell turgidity and nutrient balance.

Transpiration is essential for plants as it helps cool them down by evaporating water and maintains the concentration of sap inside the plant. This prevents the sap from becoming too diluted, which could hinder nutrient absorption and flow.

Photosynthesis is the process by which plants convert carbon dioxide and water into glucose using sunlight and chlorophyll. This glucose serves as food for the plant, fueling growth and development.

Plants require macro-nutrients in larger amounts and micro-nutrients in smaller amounts for healthy growth. Both types are essential for various physiological functions, and deficiencies can lead to growth issues.

Companion cells are closely associated with sieve tubes and help in the transport of food by providing metabolic support. They play a crucial role in maintaining the functionality of sieve tubes during nutrient transport.

Increased sunlight causes stomata to open wider, facilitating more water vapor loss, thereby increasing the rate of transpiration. This is essential for maintaining water and nutrient flow within the plant.

The thick walls of xylem vessels provide structural support and help withstand the pressure of water moving through them. This design is essential for the efficient transport of water and minerals up to various plant parts.

Phloem parenchyma consists of unspecialized, thin-walled cells that play a key role in storing food. This storage capacity is important for the plant to utilize during times of low photosynthetic activity.

Root pressure is the force generated in the roots that helps push water upward through the xylem vessels. It plays a significant role in the upward movement of water, particularly when transpiration rates are low.

Sieve tubes are the main conducting elements in the phloem, responsible for transporting organic food produced in the leaves throughout the plant. Their structure allows for efficient movement of nutrients.

Phloem fibres are non-living sclerenchyma cells that provide mechanical support to the plant. Although they do not transport food, their structural integrity is essential for maintaining the overall strength of the phloem tissue.