Growth regulators, which control plant growth and development are called___________

Growth regulators, which control plant growth and development are called___________

A. Secondary metabolites

B. Macro element

C. Nonessential elements

D. Phytohormone

Answer: Phytohormone

Growth regulators, which control plant growth and development are called Phytohormone.

What are Growth regulators in Plants?

The Plant growth regulators also called as PGRs are chemicals used to modify plant growth such as increasing branching, suppressing shoot growth, increasing return bloom, removing excess fruit, or altering fruit maturity. PGRs may be used in conjunction with other plant control products such as herbicides or insecticides to achieve a desired effect. Plant hormones such as auxins and androgens and synthetic compounds can be considered PGRs because they promote certain aspects of plant growth and allow the grower to make decisions about cropping and harvest scheduling.

What is Phytohormone?

Phytohormones or plant hormones are naturally occurring small organic molecules or substances which influence physiological processes in plants at very low concentrations. These plant hormones control many metabolic processes in plants.

What are Secondary metabolites?

The term metabolite is used to refer specifically to biochemical compounds produced by organisms, usually in small amounts. Secondary metabolites are not directly involved in the normal growth, development, or reproduction of the organism. They are, however, important for defence against predators and pathogens, for attracting pollinators or dispersal agents, for producing pigments or other characteristics that aid in recognition by other organisms, and several other functions. Some secondary metabolites are toxins while others have pharmacological properties.

What are Macro Elements?

Primary nutrient elements are macro nutrients, which are the most important vitamins, minerals and macronutrients for growth. The macro elements are the major chemical elements needed by the plant for general growth and development. In herbicides, they are nitrogen (N), phosphorus (P), and potassium (K).

What are Micro Elements?

The seven essential micronutrients are sometimes referred to as micro-elements because of their small size, in comparison to macronutrients. This group of seven elements [boron (B), zinc (Zn), manganese (Mn), iron (Fe), copper (Cu), molybdenum (Mo), chlorine (Cl)] are needed throughout the growth cycle of the plant in small amounts for optimal plant health.

What are Nonessential elements?

Nonessential elements are minerals that occur freely in the soil, but are not part of the plant’s normal metabolism. They are absorbed by the roots when in very small amounts. Nonessential elements are toxic if they are excessive in the growing media or when taken up in large amounts by the root system. These elements include lithium, strontium, tin, radium, beryllium, vanadium, mercury, silver and bromine.

Plant Growth and Development MCQs and Answers –Set-1

1. Which plant hormone helps in breaking the dormancy of plant?

2. Which hormone is formed in leaves and helps in the blooming of the flowers?

3. Which plant hormone is formed in injured cells by which the injury of plant is healed?

4. Which of the following hormone help in the cell division and development in the presence of auxins?

5. Name the plant hormone which increases the activity of cambium in the wooden plants?

6. Growth regulators, which control plant growth and development are called___________

7. Growth in plants is mainly driven by turgor pressure.

8. Which of the following is NOT a plant hormone?

9. Name the plant in which auxin was first discovered?

10. Which of the following is NOT a naturally occurring auxin?

Plant Growth and Development NEET MCQ –Set-2

1. Uneven distribution of auxins may lead to

2. Tendrils of garden peas coiling around any support signifies:

3. ____________ tissues synthesize natural cytokinins

4. ________ is a plant hormone generally present in the gaseous state

5. _________ is a colourless gas that serves as a signalling hormone.

6. Which plant hormone is responsible for saving the crops from falling.

7. Which of the following hormone is found in gaseous form?

8. Name the plant hormone which is responsible for the ripening of fruits?

9. Which plant hormone is helpful in making RNA and protein?

10. Which of the following statement is incorrect?

Important Questions on Plant Growth and Development –Set-3

1. The term auxin was coined by

2. Precursor of Indole acetic acid (natural auxin) is

3. All the following hormones are growth inhibitors except

4. Which of the following is a gaseous hormone

5. Which of the following bioassays are used to detect the presence of auxin

6. Coconut milk contains a cytokinin called ____ which promotes plant growth.

7. One of the following is not an auxin

8. _________can stimulate the germination of barley seeds

9. Seed dormancy is triggered by

10. The significance of the day length in plants was first shown in:

Plant Growth and Development NEET Questions –Set-4

1. A seed which is just waiting for favourable environmental condition to germinate is called

2. Richmond – Lang effect is

3. 2,4-D is used as

4. The type of germination in which cotyledons come above the ground is called as

5. In most of monocot plants, germination is

6. The phase of growth which is the first phase and represents lag phase of growth curve is

7. The lateral meristem in plant is responsible for

8. Plant growth can be measured by

9. Auxins were first isolated form the plants by

10. Apical dominance is due to

Plant Growth and Development Short Questions for NEET –Set-5

1. Identify the true statement/statements regarding growth and development in organisms.

2. Vernalization treatment can convert

3. Scarification is a method of overcoming dormancy in seeds which

4. Identify the precursor substance used in the biosynthesis of gibberellins in plants.

5. Seeds in which germination is stimulated by light are called

6. The chemical substances like phenolics, caumarins, ferulic acid are

7. The seeds which can not germinate in absence of light is called

8. Germination inhibitors leached out by one plant may inhibit germination of seeds of other plants is called as

9. The dormancy of seed is due to mechanical resistance of seed coat in

10. Which of the following growth harmones in plant is influenced by light?

Plant Growth and Development Class 11 questions and answers –Set-6

1. Name the amino acid which acts as a precursor of auxin biosynthesis?

2. Mark the one, which is NOT a physiological effect of auxin?

3. Name the site of Gibberellins synthesis

4. Gibberellin that is synthesized in the shoot transported to different parts of the plant by which medium?

5. What is bolting?

6. Which of the following plant hormone is responsible for seed germination?

7. Name the first naturally occurring cytokines.

8. Which of the following plant hormone causes a delay in leaf senescence?

9. Name the stress hormone of the plant.

10. Deficiency in which of the following hormone causes dwarfism in the plant?

Plant Growth and Development objective questions and Answers –Set-7

1. Who classified the plants into different categories on the basis of photoperiodic responses

2. The plant which needs light period shorter than critical period is called

3. Vernalization is also called as

4. The harmone which stimulates the flowering in vernalized plant is

5. Vernalization is

6. Epigeal germination is found in

7. Which of the following substance acts as natural germination inhibitor?

8. The part of seed which emerges out first during germination is

9. Indefinite growth of plants is due to presence of

10. In which of the following, rate of growth gradually slows down and comes to steady stage?