Plant Growth And Development Question And Answers

Biology Class 11 WBCHSE Plant Growth And Development Some Important Questions And Answers

Question 1. Which plant hormone is known as stress hormone?
Answer: Abscisic acid is known as a stress hormone as it helps the plant tolerate adverse conditions like drought, extreme cold, etc.

Question 2. Which growth control hormone is used for the rapid ripening of fruits?
Answer: Ethylene hormone is used for rapid ripening of fruits.

“plant growth and development questions and answers pdf”

Question 3. What will happen if cytokinin is not used in the culture medium?
Answer: Cytokinin hormone is important for cell division. If cytokinin is not used in the culture medium then cells will not divide properly. As a result, callus formation will be affected.

Question 4. What will happen if GA3 is applied to the seedlings of paddy?
Answer: GA3 increases the length of the internodes which results in better yield of the crops. If GA3 is applied to the paddy seedlings, they will grow in height.

Question 5. What will happen if the differentiation of dividing cells stops?
Answer: The part of the plant where differentiation of dividing cells stops remains a deformed mass of cells and the plant organs like leaves and stems would not form well. This deformed mass of cells is known as a callus.

Read and Learn More WBCHSE Solutions For Class 11 Biology

Question 6. Write the direction of growth of the vascular bundle.
Answer: Vascular bundles grow along the length of the stem. HIS What is senescence?

Question 7. What is an inflection point?
Answer: The slow deterioration of structural and functional characteristics in a mature plant due to aging is known as senescence.

“important questions on plant growth and development”

Question 8. What is seed dormancy? Mention the types of seed on the basis of seed dormancy.
Answer: The point at which the log phase ends and the lag phase starts during growth is known as an inflection point.

Class 11 Biology	Class 11 Chemistry
Class 11 Chemistry	Class 11 Physics
Class 11 Biology MCQs	Class 11 Physics MCQs
Class 11 Biology	Class 11 Physics Notes

Question 9. What is seed dormancy? Mention the types of seed on the basis of seed dormancy.
Answer:

Seed dormancy: The failure of an intact, viable seed to complete germination under favorable conditions is known as seed dormancy.

Types of seed on the basis of dormancy:

There are three types of seeds—

1. Macrobiotic,
2. Mesobiotic,
3. Macrobiotic.

Question 10. Which is the primary site of perception of photoperiodic induction?
Answer: Leaves are the primary site of perception of photoperiodic induction. Mature leaves are more sensitive to photoperiodic induction than any young and old leaves.

Question 11. Name a plant growth regulator that is not a phytohormone.
Answer: Polyamine is a plant growth regulator which is not a phytohormone.

Question 12. Which hormone is applied to plants for rapid closure of stomata?
Answer: Abscisic acid is applied to plants for rapid closure of stomata.

Question 13. What will happen if a fully ripe fruit is placed in a basket of unripe fruits?
Answer: The ethylene present in the fully ripe fruit will be released soon and induce early ripening in all the unripe fruits.

Question 14. What is the determining factor for the growth of dicot leaves?
Answer: The determining factor for the growth of dicot leaves is the upper surface area of the leaves.

“plant growth and development short answer questions”

Question 15. If an apple merchant wants to wait for the rise of the market price of the apples while increasing the size of the fruits, then which plant growth regulator will he apply?
Answer: He will use gibberellin, as this plant growth regulator helps to increase the size of the fruit and also delay the abscission. Thus he can wait till the rise of market price and he would get an increase in yield as well.

Biology Class 11 WBCHSE

Question 16. Will a leafless plant respond to photoperiodic induction? Explain with reason.
Answer: The leaves of the plant contain a covalently bound chromatophore-containing protein system called phytochrome. Phytochrome perceives the photoperiodic induction. Hence a leafless plant will not show any response to photoperiodic induction.

Question 17. How will you prove that leaves are receptors of photoperiodic induction?
Answer: If a plant with only a leaf is kept under appropriate photoperiodic conditions, then it will bloom. But if a leafless plant is kept under suitable photoperiodic conditions then it will not bloom. This proves that leaves are the site of perception of photoperiodic induction.

Question 18. What do you mean by apical dominance?
Answer: Apical dominance is the condition where the growth of the lateral buds is inhibited by the apical buds. In this case, auxin remains more active and the plant increases in height without profuse branching. Decapitation or the removal of the apical bud can deactivate the power of auxin. Thus lateral buds resume their growth to produce branches.

Question 19. What is the sigmoid growth curve?
Answer: The sigmoid growth curve is an ‘S’-shaped curve representing the average growth of all organisms, where young ones experience an initial slow growth followed by rapid accelerating growth. This is followed by continuous steady growth and as organisms reach maturity, the growth rate slows down and finally comes to a stop.

“MCQ on plant growth and development with answers”

Question 20. What is parthenocarpy?
Answer: Parthenocarpy refers to the production of fruits without fertilization. This process produces seedless fruits. Auxins are used to produce such fruits.

Biology Class 11 WBCHSE Plant Growth And Development Very Short Answer Type Questions

Question 1. What does the stationary phase of the sigmoid curve indicate?
Answer: The maturation phase or slow growth rate is indicated by the steady phase or stationary phase in a sigmoid growth curve.

Question 2. Name the growth regulator which was isolated from the endosperm of maize.
Answer: Zeatin—a cytokinin was isolated from corn kernel by Letham et al (1963).

Question 3. What is vernalisation?
Answer: Vernalisation is the promotion of flowering by treating the plant at low temperatures (1°C-2°C) in its primary growth phase.

Question 4. What would happen if soaked, light-sensitive lettuce seeds were exposed to far-red light followed by red light?
Answer: When soaked lettuce seeds are exposed to far-red light followed by exposure to red light, then the seeds will germinate. This phenomenon is known as photomorphogenesis.

Question 5. Name any two synthetic auxins used in agriculture.
Answer: 2,4-dichlorophenoxyacetic acid (2,4-D) and ff-naphthylacetic acid or 1 naphthaleneacetic acid (NAA).

“previous year questions on plant growth and development”

Question 6. What induces parthenocarpy in grapes?
Answer: Gibberellin induces parthenocarpy in grapes

Question 7. What can induce bolting in cabbage plants?
Answer: Boltingin cabbage is triggered mainly by gibberellin. Also, bolting can occur as a result of other factors such as cold spells or changes in day length (long day).

Question 8. What are quiescent seeds?
Answer: The seeds which fail to germinate due to unfavorable, external environmental conditions are called quiescent seeds.

Question 9. Name the hormone that makes the plant more tolerant to various stresses.
Answer: Abscisic acid (ABA) makes the plant tolerant to various stresses.

Question 10. Name the plant hormone that inhibits the growth of plants.
Answer: Abscisic acid (ABA) inhibits the growth of plants.

Question 11. What are the full forms of IAA, NAA, and IBA?
Answer: IAA—Indoleacetic acid, NAA—Naphthaleneacetic acid, IBA—Indole-3-butyric acid.

Question 12. What does an overripe apple release, that affects other apples in the basket?
Answer: An overripe apple releases ethylene—a gaseous hormone, that affects other applesin the basket.

Question 13. What is the growth curve?
Answer: A growth curve is constructed by plotting the increase in cell number versus time of incubation and can be used to delineate stages of the growth cycle.

Question 14. What would develop first, shoot bud or the root, from the callus of tobacco pith, grown in a sterile minimal nutrient medium, when cytokinin added is more than auxins?
Answer: Shoot bud will develop.

Question 15. Define growth regulators.
Answer: A plant growth regulator is an organic compound, either natural or synthetic, that modifies or controls one or more specific physiological processes within a plant to accelerate or inhibit growth in plants.

Question 16. Which part of the plant perceives light for flowering?
Answer: the mature leaf perceives the light stimulus for flowering. It is the organ for the perception of light.

Question 17. Name the phytohormone that stimulates the production of the enzymes that mobilize nutrients in the cotyledon in some germinating seeds.
Answer: Gibberellic acid.

Question 18. A farmer grows cucumber plants in his field. He wants to increase the number of female flowers in them. Which plant growth regulatory hormone (PGR) can be used to achieve this?
Answer: Auxin can Increase the number of female flowers in a cucumber plant. It is responsible for changes in sex expression.

“NEET questions on plant growth and development with solutions”

Question 19. In botanical gardens and tea gardens, gardeners trim the plants regularly so that they remain bushy. Does this practice have any scientific explanation?
Answer: Yes. This practice can be related to a phenomenon called apical dominance. The apical buds suppress the growth of lateral buds and prevent branch formation. If it is removed by trimming, the lateral buds start to grow to give the plant a bushy look.

Question 20. A gardener finds some broad-leaf dicot weeds growing in his lawns. What can be done to get rid of the weeds efficiently?
Answer: If the synthetic auxin 2, 4-D (2,4-dichloro phenoxy acetic acid) is sprayed over the lawns, in a particular concentration, the broad leaf dicot weeds will die, leaving the grasses alive. This is due to the selective herbicidal action of the synthetic auxin 2, 4-D.

Question 21. Name a plant hormone that can delay senescence.
Answer: Cytokinin is the plant hormone that delays senescence.

“class 11 plant growth and development questions and answers”

Question 22. Which plant hormone is called anti-aging hormone?
Answer: Cytokinin is known as an anti-aging hormone as it delays senescence.

Question 23. What is meant by apparent growth?
Answer: Apparent growth is an increase in the size, volume, and weight of the plants, which can be observed from outside.

Question 24. What is real growth?
Answer: Real growth is the formation of new cytoplasm and the accumulation of other cellular materials in the cell.

“long answer questions on plant growth and development”

Question 25. Which plant hormone is known as anti-auxin?
Answer: Abscisic acid

Question 26. While eating watermelons, all of us wish—it was seedless. As a plant physiologist can you suggest any method by which this can be achieved?
Answer: Watermelon plants can be treated with artificial auxin which will induce parthenocarpic fruit production. These fruits will be seedless.