Tag: growth in plants

Questions Related to growth in plants

Phytohormones are

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Chemicals regulating flowering

  2. Chemicals regulating secondary growth

  3. Hormones regulating growth from seed to adulthood

  4. Regulators synthesised by plants and influencing physiological processes

Show answer
Correct Option: D
Explanation:
Phytohormones are chemical substances synthesized by plants. 
These chemical substances regulate various physiological processes in plants.
So, the correct answer is 'Regulators synthesised by plants and influencing physiological processes'

Chemicals having profound effect on growth and development are

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Enzymes

  2. Phytohormones

  3. Catalytic agents

  4. Manure

Show answer
Correct Option: B
Explanation:

Phytohormones are also called as plant hormones. These are chemicals which play important role in growth and development of plants. These are involved in various physiological processes of plants like growth, flowering, fruiting, shoot and root development, etc. Phytohormones liks auxin, cytokinin act as growth promoter whereas hormones like abscisic acid, ethylene act as growth inhibitor. 

Thus, the correct answer is option B.

Through their effect on phytohormones, temperature and light control

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Stomatal closure

  2. Apical dominance

  3. Flowering

  4. Fruit development

Show answer
Correct Option: C
Explanation:

Phytohormone is the plant hormone that is involved in various processes of plants. Hormones like gibberellin induce flowering and abscisic acid inhibits flowering in plants. In plants, flowering is controlled by light and dark periods (photoperiod) and temperature in specific environments. Plant generally requires either long day or cold condition for flowering.

Thus, the correct answer is option C.

Phytohormone is a naturally produced organic substance in ________________.

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Higher plants which controls growth and development in general

  2. Plants to control growth and physiological functions at the site of its production

  3. Higher plants controlling growth and development at a site for removed from the site of its production and is effectively only when present in large quantities

  4. Higher plant controlling physiological and growth functions at a site quite removed form the site of its production and is effective when present when in minute quantities

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Correct Option: A

High concentration of hormone will

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Kill the plant

  2. Cause chlorosis in leaves

  3. Cause stunting in plants

  4. Show no effect on the plant

Show answer
Correct Option: C
Explanation:

When concentration of hormones in the plant body increases, growth of the plants decreases.

So, the correct option is cause stunting in plants’.

State whether the following statements are true or false.
A hormone is produced in small amounts in a tissue, and it causes a physiological action within that same tissue soon after its production.

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. True

  2. False

Show answer
Correct Option: B
Explanation:

A hormone is not produced in tissue but instead in an organ. The effect caused by that by that hormone can be seen in various parts of the body including the site of production. For example, insulin produced by pancreas converts the glucose present in the bloodstream into the glycogen.  

So, the correct option is 'False'.

Identify the physiological process induced by two phytohormones having a common precursor which is formed due to catalytic activity of pyruvic dehydrogenase complex
(a) More female flowers in Cucumber
(b) $\alpha$-amylase production in Barley grains
(c) Acceleration of fruit ripening in Tomato
(d) Delay in sprouting of Potato tubers.

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. a, b

  2. a, c

  3. c, d

  4. b, d

Show answer
Correct Option: C
Explanation:

Ethylene is a plant hormone. It accelerates fruit ripening in tomato. Maleic hydrazide is a type of auxin, plant hormone. It delays sprouting of potato tubers. Both these hormones have common precursor that is formed due to the catalytic activity of pyruvic dehydrogenase complex.

Thus, the correct answer is option C.