EMPOWER Disccussion Relative Humidity and Temperature
What cause the plastic bag to turn cloudy at the end of the experiment?
What triggers the water to be expelled from the plant?
Where does the water which has been expelled come from?
Which structure in the leaf helps to draw water out?
Which structure helps to control the opening and closing of stomata?
How does transpiration takes place?
What is the difference between transpiration that takes place during the day and night ?
In your opinion, if the plant is in wilt condition, does transpiration still take place? Why?
Does the water content in plant influence transpiration rate?
What are other factors which may influence transpiration to occur?
EMPOWER Answers to Discussion Relative Humidity and Temperature
There were water droplets in the bag. The bag may appear cloudy because of water vapor in the bag.
The inner side of the plant is in hot condition. Thus, to make it cooler the plant has to expelled the water out from its body.
The water comes from the soil. The uptake of water from the soil is via osmosis, then the water enters neighbouring cells until it reached the pore.
The structure which responsible in drawing the water out is stomata. Stomata are a special type of pore opening on leaves of plants. They are designed to absorb water from sources such as rain while also removing excess water in the plant through transpiration
The regulation of opening and closing of stomata is controlled by guard cell. It is one of the paired cells in the epidermis of a plant that control the opening and closing of a stoma of a leaf. When swollen with water, guard cells pull apart from each other, opening the stoma to allow the escape of water vapour and the exchange of gases. When drier, guard cells become more flaccid and move closer together, allowing the plant to conserve water.
When the plant has too much water, the guard cells open and permit the stomata to release water into the air. This water is replaced by the movement of water from neighbouring cells. Eventually water is pulled up the plant through cells in the trunk or stem by capillary action.
On a sunny day the guard cells are open and water vapour escapes through the stomata. At night the guard cells are partially or completely closed and little water escapes.
No. This is because there is no supply of water from the soil and stomata are closed. Furthermore the wilt plant needs to conserve water until the plant become turgid again.
Yes. The water content does influence the transpiration rate. The greater the water content in the plant body, the higher will be the transpiration rate.
Transpiration is actually being influenced by environmental factors. There are 5 factors altogether which are light, wind, relative humidity, temperature and soil water.
ENHANCE Have you ever seen this phenomenon before. Why does this man is sweating a lot? Explain