1 Mark Questions
Answer : Lenticels help in facilitating the process of transpiration in woody plants.
Answer : Odd term : Phagocytosis.
All the other three terms are concerned with processes in plants.
Answer : Balsam is a herbaceous plant that loses too much of water by excessive transpiration, i.e., the rate of transpiration is more than the rate of absorption. So, their stem drops and wilts during the mid day even if the soil is well watered.
Answer : Cuticle is the waxy layer on epidermis of the leaf meant to reduce transpiration.
Answer : Lenticel is the biological term used for the permanently open structures seen on the bark of an old woody stem.
Answer : Lenticels are located on the barks of the older woody stems.
Answer : Differences between Transpiration and Guttation.
Transpiration | Guttation |
Loss of water in the form of water vapour. | Loss of water in the form of water droplets. |
Occurs in the presence of sunlight. | Does not require sunlight, seen in early morning. |
Water loses through stomata, lenticels and cuticles. | Water loses through hydathodes. |
Provides cooling effect to the body. | Does not provide any cooling effect. |
May cause wilting of leaf cells by affecting turgidity. | Does not affect turgidity if leaf cells. |
Answer : Hydathodes are located on the margins of the leaves of herbaceous plants e.g., cucurbita.
Answer : The logical sequence is :
xylem, mesophyll cells, intercellular spaces, substomatal space, stoma.
Answer : iii) Loss of water as droplets from hyhdathodes (water glands) is called guttation.
Answer : Bleeding is the exudation of cell sap from any injured or cut part of a plant, due to increased root pressure.
Answer : On a bright Sunny day, the cells of the leaves lose water due to transpiration and thus lose their turgidity.
This causes the leaves to roll up and thus reduce transpiration.
Answer : Hydathodes are the structures involved in the guttation process that occurs in the plants.
Answer : Bleeding is known as the loss of water from injured parts of plants.
Answer : On a hot day, the stomata are fully open and the rate of transpiration is more than the rate of absorption. This leads to wilting in them.
Answer : Bleeding is the biological term for the exudation of sap from injured parts of a plant.
Answer : Guttation is the process by which plant loses water in the form of droplets through pores (hydathodes).
Answer : Location : Stoma are found on epidermis of the leaves.
Function : They help in the process of transpiration.
Answer : Xerophytes grow in scarcity of water. So, in order to decrease the rate of transpiration, their leaves are modified into spines or reduced in size.
Answer : Location :Lenticels are located on the barks of the older woody stems.
Function : Lenticels help in facilitating the process of transpiration in woody plants.
Answer : Ganong’s potometer is used to measure the rate of transpiration.
Limitations:
i) Introducing air bubble is difficult.
ii) Amount of water loss through transpiration cannot be measured.
Answer : Transpiration is the loss of water in the form of water droplets from the margin of leaves.
Answer : Guttation is the technical term for the loss of water in the form of water droplets from the margin of leaves.
Answer : Guard cells are the part of stomatal apparatus found in the epidermis of leaves.
Function : They help to regulate the rate of transpiration by opening and closing the stomata.
Answer : Transpiration is the loss of water in the form of water vapour from the aerial parts of plant.
Answer : Two advantages of transpiration to plants are:
i) It helps in upward movement of water and minerals from the plants.
ii) It controls the rate of water being absorbed by the roots.
Answer : Stomata : Transpiration : : Hydathodes : Guttation.