Chapter 4 Quiz 2 (2nd Secondary Biology)

The figure below represents a physiological phenomenon related to water given out in the form of droplets. The statement "Occurs almost in all plants" is not related to this phenomenon as it does not provide any information about the water being given out in droplets or its purity.

In higher Angiosperms, water is primarily lost from the aerial parts of plants through stomata transpiration. Stomata are small openings on the surface of leaves that allow for gas exchange, including the release of water vapor. This process is essential for the plant's survival as it helps to regulate temperature, facilitate nutrient uptake, and maintain turgidity. Cuticular transpiration refers to water loss through the waxy cuticle layer on the surface of leaves, while lenticular transpiration occurs through lenticels, which are small openings in the bark of woody stems. Guttation is the process of water being excreted from specialized structures called hydathodes and is not the main mechanism of water loss in higher Angiosperms.

When guard cells lose water, they become flaccid and close, leading to the closure of stomata. This is because when guard cells lose water, the turgor pressure decreases and the cells shrink, causing the stomatal pore to close. This mechanism helps to prevent excessive water loss from the plant and regulate gas exchange.

During the night, photosynthesis does not occur in plants, so they rely on respiration. In respiration, oxygen is taken in and carbon dioxide is released. Therefore, statement I is correct. During the day, photosynthesis takes place, where plants take in carbon dioxide and release oxygen. This is the opposite of respiration, so statement II is also correct. Therefore, both statements I and II are correct.

When wind speed increases, the rate of transpiration also increases. This is because wind helps in removing the water vapor that is evaporating from the leaves, creating a drier environment around the plant. As a result, the plant tends to lose more water through transpiration to maintain its water balance. Therefore, an increase in wind speed leads to an increase in the rate of transpiration.

not-available-via-ai

Plants store excretory waste products in cellular vacuoles. Vacuoles are membrane-bound organelles found in plant cells that serve as storage compartments. They can store various substances, including waste products produced by the plant's metabolic processes. These waste products are stored in cellular vacuoles until they can be safely eliminated from the plant's system.

The correct answer is (A) remains turgid and green to a great extent / (B) wrinkled appearance / (C) looks fresh and is not affected at all / (D) wilts completely.

This observation can be explained by the fact that stomata are mainly present on the lower surface of the leaf. When the lower surface is vaselined (leaf A), the stomata are blocked, resulting in a decrease in transpiration and water loss. As a result, the leaf remains turgid and green.

When the upper surface is vaselined (leaf B), the stomata on the lower surface are still able to function, allowing for transpiration and water loss. However, the stomata on the upper surface are blocked, leading to a decrease in overall transpiration. This causes the leaf to lose water and appear wrinkled.

When both surfaces are vaselined (leaf C), all stomata are blocked, resulting in a complete cessation of transpiration. Without transpiration, the leaf wilts completely.

When no vaseline is applied (leaf D), both the upper and lower stomata are able to function, allowing for transpiration and water loss. As a result, the leaf remains turgid and green to a great extent.

Transpiration occurs in the daytime because that is when the sun is shining and the temperature is higher. Transpiration is the process by which plants release water vapor through their leaves. During the day, the sunlight provides the energy needed for transpiration to occur. The high temperature also increases the rate of evaporation from the leaves, leading to more water vapor being released. At night, when the temperature is lower and there is no sunlight, transpiration slows down or stops altogether.

Plants produce both carbon dioxide and oxygen because carbon dioxide is a waste product of respiration, which occurs in plant cells, and oxygen is a waste product of photosynthesis, which also occurs in plant cells. During respiration, plants break down glucose to release energy, producing carbon dioxide as a byproduct. In photosynthesis, plants use sunlight to convert carbon dioxide and water into glucose and oxygen. Therefore, plants produce both carbon dioxide and oxygen as waste products of these essential processes.

Guttation is the process by which plants excrete excess water in the form of droplets through special openings called hydathodes. This process occurs when the rate of water absorption by the roots exceeds the rate of transpiration. Therefore, the correct answer is "Get rid of excess of water."

Lenticels are openings in the bark of plants that allow for gas exchange between the internal tissues and the external environment. They are typically found in woody stems and branches and serve as a pathway for oxygen to enter and carbon dioxide to exit the plant. Lenticels also play a role in the release of excess water vapor.

When hydrous copper sulphate is added to water drops, its color will remain the same. This is because hydrous copper sulphate is a blue compound, and when it dissolves in water, it forms copper ions (Cu2+) and sulphate ions (SO4^2-). The presence of water does not cause any chemical reaction that would change the color of the copper ions. Therefore, the color of the hydrous copper sulphate remains unchanged.

All of the given options explain how mangrove trees are able to survive in salty water. The first option states that mangroves squeeze out extra salt through special pores in their leaves, which helps them tolerate the high salt levels. The second option mentions that mangroves have a substance in their roots that filters out a large percentage of the salt in seawater, allowing them to take in only the necessary amount. The third option explains that mangroves concentrate salt in older leaves, which are eventually shed, thereby removing the excess salt from their system. Therefore, all of these mechanisms contribute to the survival of mangroves in salty conditions.

Guard cells are responsible for the opening and closing of pores, known as stomata, in plants. Stomata are essential for gas exchange, allowing plants to take in carbon dioxide for photosynthesis and release oxygen and water vapor. Guard cells control the opening and closing of stomata by changing their shape. When the guard cells are turgid, the stomata open, allowing gas exchange. Conversely, when the guard cells lose water and become flaccid, the stomata close, preventing excessive water loss. Therefore, the correct answer is guard cells.

Cooling of plants is caused by transpiration. Transpiration is the process by which plants release water vapor through small openings called stomata on their leaves. As the water evaporates from the leaves, it cools down the plant. This cooling effect is similar to how sweating cools down our bodies. Guttation is the process by which plants release liquid droplets from the tips of their leaves, but it does not directly contribute to cooling. Photosynthesis is the process by which plants convert sunlight into energy, and respiration is the process by which they release energy from stored sugars, but neither of these processes directly cause cooling.

Both transpiration and guttation are affected by the change of the season. Transpiration is the process by which plants lose water through their leaves, and it is influenced by factors such as temperature, humidity, and wind. The change of the season can affect these factors and therefore impact the rate of transpiration. Guttation, on the other hand, is the process by which plants release liquid water from specialized structures called hydathodes. This process is also influenced by environmental factors and can be affected by the change of the season. Therefore, both transpiration and guttation are indeed affected by the change of the season, but they differ in the nature and amount of water loss.

Without the table or any information about the environmental conditions and the rate of transpiration for each plant, it is impossible to provide an explanation for why option A is the correct answer.

The water column inside vessels and tracheids does not rupture during the ascent of sap due to cohesion and adhesion. Cohesion refers to the attraction between water molecules, causing them to stick together, while adhesion refers to the attraction between water molecules and the walls of the vessels and tracheids. These forces of cohesion and adhesion help to maintain the integrity of the water column and prevent it from breaking apart as water is pulled up through the plant.

As temperature increases, the rate of transpiration increases because water molecules diffuse from the leaf faster. This is because higher temperatures increase the kinetic energy of the water molecules, causing them to move more rapidly and escape from the leaf's surface more quickly. As a result, the rate of transpiration, which is the loss of water vapor from the leaf, increases.

Desert plants need to conserve water due to the scarcity of water in their environment. Having fewer numbers of stomata on the leaves is an adaptation that helps in reducing water loss through transpiration. Stomata are tiny openings on the surface of leaves that allow for gas exchange, but they also allow water to escape. By having fewer stomata, desert plants can minimize water loss and conserve water.

The process depicted in the figure refers to stomatal transpiration. Stomatal transpiration is the loss of water vapor through the stomata, which are small openings on the surface of leaves. These stomata regulate the exchange of gases and water vapor between the plant and its environment. During stomatal transpiration, water vapor diffuses out of the plant through the stomata, helping to regulate temperature, transport nutrients, and maintain cell turgidity. This process is crucial for plant survival and plays a significant role in the water cycle.

Hot dry and windy conditions speed up the rate of transpiration because heat increases the evaporation of water from the leaves, dryness creates a concentration gradient that promotes water movement out of the plant, and wind removes the water vapor from the leaf surface, maintaining a low humidity around the plant.

Guttation is the process in which water is lost from the tips of some leaves. This occurs when excess water pressure builds up in the plant's xylem vessels, causing water to be forced out through specialized structures called hydathodes. This process is different from transpiration, which is the loss of water vapor from the plant's leaves, and evaporation, which refers to the conversion of liquid water into water vapor. Exudation, on the other hand, refers to the release of substances such as sap or resin from plants.

When light intensity is increased, the stomata open wider to allow more carbon dioxide into the leaf for photosynthesis. This wider opening of stomata also allows more water to escape from the leaf through transpiration. As a result, the rate of transpiration increases.

Guttation is the process by which water is excreted from the leaves of plants through specialized structures called hydathodes. This process occurs due to a pushing force, as water is forced out of the plant through pressure buildup in the xylem. On the other hand, transpiration is the process by which water is lost from the leaves of plants through small openings called stomata. This process occurs due to a pulling force, as water molecules evaporate from the leaves and create a negative pressure gradient that pulls more water up from the roots. Therefore, statement 1 is correct in stating that guttation occurs by a pushing force, and statement 2 is correct in stating that transpiration occurs by a pulling force.

An increase in the movement of air around a plant, falling carbon dioxide concentrations in the plant cells, and air temperatures of 36 °C are all conditions that are necessary for stomata opening. However, the humidity of the air surrounding the plant rising is not necessary for stomata opening. Stomata open in response to a decrease in water potential in the guard cells, which is caused by factors such as light, temperature, and carbon dioxide concentration. Humidity does not directly affect the water potential of the guard cells, so it is not necessary for stomata opening.

not-available-via-ai

Low atmospheric pressure means that there is less pressure pushing down on the surface of the leaves, which allows for an easier escape of water vapor through the stomata. As a result, the rate of transpiration increases.

The Elodea plant, being an aquatic plant, lives in fresh water and therefore does not need to excrete excess water or waste products like terrestrial plants do. The plant reuses the CO2 produced from respiration and stores organic salts and acids in its cells. However, it cannot reuse the O2 produced from photosynthesis because it is a byproduct of the plant's metabolic processes and is released into the surrounding water.

The correct answer is Stomata of stem. Stomata are small openings found on the surface of leaves and stems that allow for gas exchange, including the release of water vapor through transpiration. While stomata are primarily found on the leaves, they can also be present on the stems. Therefore, the plant in the figure shown is likely transpiring through the stomata on its stem.

When a plant closes its stomata, it is unable to take in carbon dioxide for photosynthesis. Stomata are small openings on the surface of leaves that allow gases to enter and exit the plant. Carbon dioxide is necessary for the process of photosynthesis, where plants convert sunlight into energy. By closing its stomata, the plant is preventing the entry of carbon dioxide, which hinders its ability to perform photosynthesis effectively.

If an air bubble is formed in the water found in the capillary tube, the water level above the air bubble in the capillary tube rises. This is because transpiration, the process by which water is transported through plants, creates a negative pressure or tension in the xylem vessels. This tension pulls water up from the roots to the leaves. When an air bubble is formed, it disrupts the continuous flow of water, causing the tension to increase. As a result, more water is pulled up from below the air bubble, causing the water level above the air bubble in the capillary tube to rise.

In summer afternoons, the rate of transpiration in plants is higher than the rate of absorption. This means that plants lose more water through their leaves than they can take up from the soil. As a result, the plants may experience temporary wilting, where their leaves droop and become limp. This is a defense mechanism to reduce water loss and conserve moisture. However, once the temperature cools down or water availability increases, the plants will recover and regain their turgidity.

Guttation refers to the process of exudation of xylem sap from the leaves of plants. This usually occurs during the night when the plant's stomata are closed, and excess water pressure builds up in the xylem vessels. As a result, the sap is forced out through specialized structures called hydathodes, which are found at the tips or edges of leaves. Guttation is different from transpiration, as it involves the release of liquid instead of water vapor.

The correct answer is Transpiration – Guttation. The graph shows a gradual increase in water loss from the plant during the first few days of April, which is characteristic of transpiration. However, on the last day of the graph, there is a sudden spike in water loss, indicating guttation. Guttation is the process by which water is excreted from the plant through specialized structures called hydathodes. Therefore, the correct processes represented by (A) and (B) on the graph are transpiration and guttation, respectively.

Amino acids are not excretory substances of plants because they are essential building blocks for proteins and are used in various metabolic processes. Plants do not excrete amino acids, but rather utilize them for growth and development. Water, carbon dioxide, and oxygen, on the other hand, are excretory substances in plants. Water is excreted through transpiration, carbon dioxide is released during respiration, and oxygen is released as a byproduct of photosynthesis.

Guttation is the process by which plants excrete excess water and dissolved substances, including phosphate ions, through specialized structures called hydathodes. These hydathodes are found at the tips or edges of leaves and allow the plant to release excess water and ions through droplets. Therefore, guttation helps the plant to get rid of excess phosphate ions.

The likely readings on the spring balances after three days would be equal. This can be inferred from the diagram, where both shoots are at the same height and have the same number of leaves. Therefore, they would experience similar transpiration rates, resulting in equal readings on the spring balances.

Transpiration is the process by which water is lost from a plant through its leaves. If transpiration stops, the supply of water to plant parts would stop, especially the higher ones. This is because transpiration creates a suction force that pulls water up through the plant's vascular system. Without transpiration, this suction force would not be present, and water would not be able to reach the higher parts of the plant. Therefore, the correct statement in this case would be that the supply of water to plant parts would stop, especially the higher ones.

Guttation is the process by which plants release excess water droplets through specialized structures called hydathodes. High humidity creates a moist environment around the plant, reducing the rate of evaporation and allowing water to accumulate in the plant tissues. This accumulation of water eventually leads to guttation. Therefore, high humidity favors the occurrence of guttation.

The readings of this apparatus do not reflect the accurate amount of transpired water because not all of the water taken up by the leafy shoot will be transpired. Some of the water might be used for photosynthesis or for maintaining cell turgidity, rather than being transpired.

High wind speed can prevent the accumulation of water vapor around the leaves, which in turn promotes the movement of air molecules around the leaves. This movement helps to remove the water vapor and maintain a concentration gradient between the leaf and the atmosphere, allowing for efficient transpiration. Therefore, despite the high percentage of humidity, the rate of transpiration may not be affected by high wind speed.

CO2 remains inside the plant, gets dissolved in the xylem sap, and is then transported towards the apex. This is because CO2 is produced in the root cells through respiration and needs to be transported to the leaves for photosynthesis. CO2 reacts with water forming carbonic acid H2CO3 which is ionized into H+ and HCO3-. The H+ ions are used in the soil's cation exchange, which helps in the absorption of nutrients by the roots.

In an experiment to measure the rate of transpiration, the two flasks (A) and (B) contain similar leafy branches submerged in water. Flask (A) is in an area of high atmospheric pressure, while flask (B) is in an area of low atmospheric pressure. Transpiration is the process by which water is lost from the leaves of plants through evaporation. In this experiment, the difference in atmospheric pressure between the two flasks will affect the rate of transpiration. Higher atmospheric pressure in flask (A) will result in less water being lost through transpiration compared to flask (B) with lower atmospheric pressure. Therefore, the water amount in flask (B) will be less than in flask (A) after a few hours of the experiment.

Plants have various methods to get rid of their waste products. The first method is through stomata and lenticels, where gaseous waste is released. The second method is by shedding leaves and falling of fruits, which helps in getting rid of stored solid wastes. The third method involves converting soluble toxic substances into insoluble crystals inside the cell vacuoles. Therefore, all three statements - 1, 2, and 3 - are correct.

Water gets from the leaf to the atmosphere by evaporating into the air spaces and then diffusing through the stomata. This process allows water molecules to escape from the leaf and enter the surrounding air. Evaporation occurs when water molecules gain enough energy to break free from the liquid phase and become a gas. The air spaces within the leaf provide a pathway for the water vapor to move towards the stomata, which are small openings on the leaf surface. Through diffusion, the water vapor moves from an area of high concentration (inside the leaf) to an area of low concentration (outside the leaf) until it reaches the atmosphere.

Transpiration is the process by which water is lost from the leaves of plants through small openings called stomata. As water evaporates from the leaf surface, it creates a negative pressure or tension in the leaf cells. This negative pressure is known as suction force, which helps in the movement of water and nutrients from the roots to the leaves. Therefore, suction force is the type of pressure created in leaf cells due to transpiration.

To study the mechanism of transpiration in plants, one would need to examine the stomata, rate of water absorption, and atmospheric temperature. Stomata are small openings on the surface of leaves that regulate the exchange of gases and water vapor. The rate of water absorption refers to the uptake of water by the roots and its movement through the plant. Atmospheric temperature plays a crucial role in transpiration as it affects the rate of evaporation of water from the leaves. Therefore, by examining these factors together, one can gain a comprehensive understanding of the transpiration process in plants.

Transpiration in plants is closely similar to sweating in humans. Both processes involve the loss of water from the organism. In plants, transpiration occurs through the stomata on the leaves, where water evaporates and is released into the atmosphere. Similarly, in humans, sweating occurs through the sweat glands in the skin, where water evaporates and helps regulate body temperature. Both transpiration and sweating are important mechanisms for maintaining water balance and temperature regulation in plants and humans, respectively.

Leaves in areas of low humidity have a steeper concentration gradient, meaning there is a greater difference in water concentration between the inside and outside of the leaf. This causes water to diffuse out of the leaf at a faster rate.

By evaporation, you can differentiate between two equal amounts of water, one resulting from transpiration and the other from guttation. Transpiration is the process by which plants release water vapor through their leaves, while guttation is the process by which plants release liquid water through specialized structures called hydathodes. When both types of water are exposed to evaporation, the water resulting from guttation will leave behind salts and other impurities, while the water resulting from transpiration will evaporate without leaving any residue.

Xylem sap is the primary substance excreted from the plant via guttation. Guttation is the process by which plants release excess water and dissolved substances through specialized structures called hydathodes. Xylem sap is the fluid that is transported through the xylem vessels in plants, carrying water, minerals, and other dissolved substances. During guttation, the excess water and dissolved substances, including sugars, hormones, and minerals, are released from the plant through the hydathodes in the form of droplets. Therefore, the correct answer is xylem sap.

Transpiration is the process by which water is pulled upward in plants from the roots to the leaves. It occurs when water evaporates from the leaves, creating a negative pressure or tension that pulls water up through the xylem. Root pressure, on the other hand, is the pushing force exerted by the roots to move water up the plant. This pressure is generated by the active transport of ions into the root cells, which creates a concentration gradient that drives water uptake. Together, transpiration and root pressure work in tandem to move water upward in plants.

Guttation is the process by which plants release excess water in the form of droplets from specialized structures called hydathodes. This occurs when root pressure forces water up from the roots and into the xylem vessels of the plant. As water is pushed up through the xylem, it eventually reaches the leaves and exits through the hydathodes, resulting in guttation. Therefore, the correct answer is root pressure.

Guttation in plants refers to the process of excreting excess water and dissolved substances from the tips of leaves. This process occurs when the transpiration rate is low and the root pressure is high. By excreting excess substances, guttation helps to regulate the concentration of organic and inorganic substances within the plant. Therefore, the correct answer is "Decreases the amount of organic and inorganic substances."

Both processes help eliminate excess water and toxic wastes from the organism's body; while sweating is regulated by sweat glands, transpiration is mainly regulated by stomata. This statement correctly differentiates between transpiration in plants and sweating in humans by explaining their roles in eliminating excess water and toxic wastes. It highlights that sweating is regulated by sweat glands, while transpiration is mainly regulated by stomata. The other statements correctly differentiate between the two processes, making this statement the exception.

Plants that grow in the shade have thinner leaves because they receive less sunlight. Thinner leaves have a larger surface area to volume ratio, which increases the rate of cuticular transpiration. Cuticular transpiration is the loss of water through the cuticle, the waxy layer on the surface of leaves. Therefore, the correct answer is that the rate of cuticular transpiration increases in plants that grow in the shade.

The correct answer is "Plants have guard cells that leave stomata permanently open to regulate transpiration." This statement is not a way plants control water loss because guard cells actually regulate the opening and closing of stomata to control transpiration. When stomata are open, water is lost through transpiration, so leaving them permanently open would increase water loss rather than control it.

not-available-via-ai

During midday, when the rate of photosynthesis increases in a terrestrial plant, it requires more energy for the plant to carry out the process. This increased energy demand leads to an increased uptake of water from the soil through the plant's roots. Therefore, the consequence of the increased rate of photosynthesis would be an increase in the amount of water absorbed from the soil.

Plants which do not contain chlorophyll produce the highest amount of CO2 in the atmospheric air because chlorophyll is necessary for photosynthesis, which is the process that converts CO2 into oxygen. Without chlorophyll, these plants are not able to perform photosynthesis and therefore do not consume CO2. As a result, they release more CO2 into the atmosphere compared to other types of plants.