Transpiration Questions and Answers ICSE Class 10

1 Mark Questions

Question 1 : State the function of lenticels.

Answer : Lenticels help in facilitating the process of transpiration in woody plants.

Question 2 : Identify the odd one in a set given below and name the category to which the remaining belong:

Transpiration, photosynthesis, phagocytosis, guttation.

Answer : Odd term : Phagocytosis.

All the other three terms are concerned with processes in plants.

Question 3 : Give scientific reason why balsam plants wilt during mid day even if the soil is well watered.

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.

Question 4 : Name the waxy layer on the epidermis of the leaf meant to reduce transpiration.

Answer : Cuticle is the waxy layer on epidermis of the leaf meant to reduce transpiration.

Question 5 : Give the biological /technical terms for the permanently open structures seen on the bark of an old woody stem.

Answer : Lenticel is the biological term used for the permanently open structures seen on the bark of an old woody stem.

Question 6 : Give the exact location of lenticels.

Answer : Lenticels are located on the barks of the older woody stems.

Question 7 : Differentiate between the transpiration and guttation on the basis of structures involved.

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.

Question 8 : Give the exact location of hydathodes.

Answer : Hydathodes are located on the margins of the leaves of herbaceous plants e.g., cucurbita.

Question 9 : Given below is a set of five terms. Rewrite the terms in logical sequence as directed at the end of the statement.

Stoma, mesophyll cells, xylem, substomata space, intercellular space (loss of water due to transpiration).

Answer : The logical sequence is :

xylem, mesophyll cells, intercellular spaces, substomatal space, stoma.

Question 10 : Choose the correct answer to the following statement out of the three choices given after the statement.

Loss of water as droplets from hydathodes is called

i) Transpiration

ii) Bleeding

iii) Guttation

Answer : iii) Loss of water as droplets from hyhdathodes (water glands) is called guttation.

Question 11 : Explain the term bleeding in plants.

Answer : Bleeding is the exudation of cell sap from any injured or cut part of a plant, due to increased root pressure.

Question 12 : Account for the following:

The leaves of certain plants roll upon a bright sunny day.

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.

Question 13 : Give the specific function of the hydathodes in the plant body.

Answer : Hydathodes are the structures involved in the guttation process that occurs in the plants.

Question 14 : Identify/name the following process/terms for the statement given below:

The loss of water from injured parts of plant.

Answer : Bleeding is known as the loss of water from injured parts of plants.

Question 15 : Account for the given below briefly. Herbaceous plants growing in well-watered soils are found to wilt on a hot day.

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.

Question 16 : Give the technical /biological term for the exudation of sap from injured parts of a plant.

Answer : Bleeding is the biological term for the exudation of sap from injured parts of a plant.

Question 17 : Explain the term guttation.

Answer : Guttation is the process by which plant loses water in the form of droplets through pores (hydathodes).

Question 18 : Give the exact location and one function of stoma.

Answer : Location : Stoma are found on epidermis of the leaves.

Function : They help in the process of transpiration.

Question 19 : Xerophytes have their leaves modified to spines or reduced in size. Explain.

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.

Question 20 :  Give the exact location and one function of lenticels.

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.

Question 21 : What is Ganong’s potometer used for? Write any two limitations of this apparatus.

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.

Question 22 : Given below biological statements which are incomplete and hence incorrect. Rewrite the correct form of the statement by inserting a suitable word at the right place. Do not delete any word already given in the statement. Underline the inserted word/words.

Transpiration is the loss of water from the leaves of the plant.

Answer : Transpiration is the loss of water in the form of water droplets from the margin of leaves.

Question 23 : Give the technical term for the following:

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.

Question 24 : Mention where in living organisms, the following located and state its main function Guard cells

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.

Question 25 : Define transpiration.

Answer : Transpiration is the loss of water in the form of water vapour from the aerial parts of plant.

Question 26 : List any two advantages of transpiration to a 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.

Question 27 : Note the relationship between the first two words and suggest that suitable word/words for the fourth place.

Stomata : Transpiration : : Hydathodes : ……………………….

Answer : Stomata : Transpiration : : Hydathodes : Guttation.