How do you calculate transpiration rate?
The rate of transpiration can be calculated by measuring the distance travelled by an air bubble in a capillary tube over a given time. The faster the bubble moves, the greater the rate of water uptake – and so the greater the assumed rate of transpiration.
What factors affect rate of transpiration?
The rate of transpiration is affected by several factors, including:
- temperature.
- humidity.
- wind speed.
- light intensity.
Is a high rate of transpiration good?
Transpiration can be hazardous to plants if there is a higher rate of transpiration than rate of moisture absorption through the roots. This is called moisture stress or plant stress. This often happens to houseplants in the winter months when we increase the ambient temperature.
What causes high rate of transpiration?
Relative humidity: As the relative humidity of the air surrounding the plant rises the transpiration rate falls. It is easier for water to evaporate into dryer air than into more saturated air. Wind and air movement: Increased movement of the air around a plant will result in a higher transpiration rate.
What decreases the rate of transpiration?
Because cooler air holds less water, its relative humidity increases or it is ‘moister air’. Therefore, warmer air will increase the driving force for transpiration and cooler air will decrease the driving force for transpiration.
How plants reduce the rate of transpiration?
Waxy cuticles, trichomes (leaf hairs), sunken stomates, and other leaf adaptations also help reduce transpiration rates by keeping the leaf surface cool or protecting it from air currents that increase evaporation.
How do plants respond to high rates of transpiration?
(1997) hypothesized that transpiration-linked accumulation of guard cell apoplastic Suc is a mechanism by which plants respond to high transpiration rate. The present study is a test of that hypothesis.
How do plants reduce the rate of transpiration?
The leaves in hot or dry environments may be adapted to reduce transpiration . For example, their stomata may open at night and close at midday. This is the reverse of what usually happens, and it means that the stomata are closed when the rate of transpiration would be greatest.
How do plants control the rate of transpiration?
Leaf stomates are the primary sites of transpiration and consist of two guard cells that form a small pore on the surfaces of leaves. The guard cells control the opening and closing of the stomates in response to various environmental stimuli and can regulate the rate of transpiration to reduce water loss.
What is the rate and unit rate?
A rate is a ratio that compares two quantities of DIFFERENT. kinds of UNITS. A unit rate has a denominator of 1 unit when the rate is written as a fraction. To write a rate as a unit rate: divide the numerator and the denominator of the rate by the denominator.
How do you calculate water loss per hour?
Convert any weight loss to ounces or ml of fluid. Check/measure the amount of fluid consumed during training. Add the amount of fluid lost to the amount of fluid consumed to get total fluid losses. Divide the total amount of fluid lost by the number of hours of training to get fluid losses per hour.
What increases the rate of transpiration in leaves?
Factors affecting transpiration
| Factor | Change in factor that increases transpiration rate | Explanation |
|---|---|---|
| Air movement | Increase | Removes water vapour from leaf surfaces. More water diffuses from the leaf. |
| Light intensity | Increase | Increases the rate of photosynthesis. Stomata open so that water diffuses out of the leaf. |
What is the rate of transpiration when temperature increases?
Plants transpire more rapidly at higher temperatures because water evaporates more rapidly as the temperature rises. At 30°C, a leaf may transpire three times as fast as it does at 20°C. Hence option B is correct.
How do environmental factors affect the rate of transpiration?
Transpiration increases with increasing air temperature and wind velocity. At constant temperature and wind velocity, transpiration rate is governed by moisture content of air. Transpiration also increases with decreasing relative humidty at constant wind velocity.
Why do different plants have different transpiration rates?
Different species of plants transpire at different rates because each of them are made differently. Some have thick tissue on their leaves, while others have thin tissue. Some have larger surface area on their leaves, while others are smaller.
Does humidity increase transpiration?
As the relative humidity of the air surrounding the plant rises the transpiration rate decreases. It is easier for water to evaporate into dryer air than into more saturated air. Increased movement of the air around a plant will result in a higher transpiration rate.