Text Book Back Questions and Answers - Chapter 5 Plant Tissue Culture 12th Biology Botany Guide Samacheer Kalvi Solutions - SaraNextGen [2024-2025]

Updated By SaraNextGen

On April 24, 2024, 11:35 AM

Plant Tissue Culture
Text Book Back Questionsand Answers
Choose the correct answer from the given option
Question 1.
Totipotency refers to
(a) capacity to generate genetically identical plants
(b) capacity to generate a whole plant from any plant cell / explant
(c) capacity to generate hybrid protoplasts
(d) recovery of healthy plants from diseased plants
Answer:
(b) capacity to generate a whole plant from any plant cell / explant
Question 2.
Micro propagation involves
(a) vegetative multiplication of plants by using micro-organisms
(b) vegetative multiplication of plants by using small explants
(c) vegetative multiplication of plants by using microspores
(d) Non-vegetative multiplication of plants by using microspores and megaspores Answer:
(b) vegetative multiplication of plants by using small explants
Question 3.
Match the following:

(a) C A D B
(b) A C B D
(c) B A D C
(d) D B C A
Answer:
(a) C A D B
Question 4.
The time duration for sterilization process by using autoclave is minutes and the temperature is
(a) 10 to 30 minutes and $125^{\circ} \mathrm{C}$
(b) 15 to 30 minutes and $121^{\circ} \mathrm{C}$
(c) 15 to 20 minutes and $125^{\circ} \mathrm{C}$
(d) 10 to 20 minutes and $121^{\circ} \mathrm{C}$
Answer:
(b) 15 to 30 minutes and $121^{\circ} \mathrm{C}$
Question 5.
Which of the following statement is correct?
(a) Agar is not extracted from marine algae such as seaweeds
(b) Callus undergoes differentiation and produces somatic embryoids
(c) Surface sterilization of explants is done by using mercuric bromide
(d) $\mathrm{PH}$ of the culture medium is 5.0 to 6.0
Answer:
(d) $\mathrm{PH}$ of the culture medium is 5.0 to 6.0
Question 6.
Select the incorrect statement from given statements:
(a) A tonic used for cardiac arrest is obtained from Digitalis purpuria
(b) Medicine used to treat Rheumatic pain is extracted from Capsicum annum
(c) An anti-malarial drug is isolated from Cinchona officinalis
(d) Anti-carcinogenic property is not seen in Catharanthus roseus.
(e) All the above are correct
Answer:
(e) All the above are correct
Question 7.
Vims free plants are developed from
(a) Organ culture
(b) Meristem culture
(c) Protoplast culture
(d) Cell suspension culture
Answer:
(b) Meristem culture

Question 8.
The prevention of large scale loss of biological integrity
(a) Biopatent
(b) Bioethics
(c) Biosafety
(d) Biofuel
Answer:
(c) Biosafety
Question 9.
Cryopreservation means it is a process to preserve plant cells, tissues or organs
(a) at very low temperature by using ether
(b) at very high temperature by using liquid nitrogen
(c) at very low temperature of-196 by using liquid nitrogen
(d) at very low temperature by using liquid nitrogen
Answer:
(c) at very low temperature of-196 by using liquid nitrogen
Question 10.
Solidifying agent used in plant tissue culture is
(a) Nicotinic acid
(b) Cobaltous chloride
(c) EDTA
(d) Agar
Answer:
(d) Agar
Question 11.
What is the name of the process given below? Write its 4 types.
Answer:

Question 12.
How will you avoid the growing of microbes in nutrient medium during culture process? What are the techniques used to remove the microbes? Answer:
The microbial growth in culture medium can be overcome by autoclaving the medium at Plant Tissue Culture II $121^{\circ} \mathrm{C}$ (15 psi) for 15 to 30 minutes.

Chemical sterilization using chemicals, sterilizing using UV radiation. Alcoholic sterilization using ethanol, autoclaving and filtration etc., are the various techniques used to remove microbes.
Question 13.
Write the various steps involved in cell suspension culture.
Answer:
Step 1: Growing of cells/callus in medium (Single or aggregates).
Step 2 : Transfer of callus to a liquid medium.
Step 3: Agitation of callus using rotary shaker.
Step 4: Filtration and separation of cells.
Question 14.
What do you mean by Embryoids? Write its application.
Answer:
Somatic embryogenesis is the formation of embryos from the callus tissue directly and these embryos are called Embryoids or from the in vitro cells directly form pre-embryonic cells which differentiate into embryoids.
Applications:
1. Somatic embryogenesis provides potential plantlets which after hardening period can establish into plants.
2. Somatic embryoids can be used for the production of synthetic seeds.
3. Somatic embryogenesis is now reported in many plants such as Allium sativum, Hordeum vulgare, Oryza sativa, Zea mays and this is possible in any plant.
Question 15.
Give the examples for micro propagation performed plants.
Answer:
Pineapple, banana, strawberry and potato.
Question 16.
Explain the basic concepts involved in plant tissue culture.
Answer:

Basic concepts of plant tissue culture are totipotency, differentiation, dedifferentiation and redifferentiation.
1. Totipotency: The property of live plant cells that they have the genetic potential when cultured in nutrient medium to give rise to a complete individual plant.
2.Differentiation: The process of biochemical and structural changes by which cells become specialized in form and function.
3. Redifferentiation: The further differentiation of already differentiated cell into another type of cell. For example, when the component cells of callus have the ability to form a whole plant in a nutrient medium, the phenomenon is called redifferentiation.
4. Dedifferentiation: The phenomenon of the reversion of mature cells to the meristematic state leading to the formation of callus is called dedifferentiation. These two phenomena of redifferentiation and dedifferentiation are the inherent capacities of living plant cells or tissue. This is described as totipotency.
Question 17.
Based on the material used, how will you classify the culture technology? Explain it.
Answer:
Based on explants used culture technology are of following types:
1. Organ culture - Embryos, anthers, root and shoot part are used.
2. Meristem culture-Meristematic tissues are used.
3. Protoplast culture - Protoplasts are used.
4. Cell culture - Single cells or aggregate of cells from callus are used.
Question 18.
Give an account on Cryopreservation.
Answer:
Cryopreservation, also known as Cryo-conservation, is a process by which protoplasts, cells, tissues, organelles, organs, extracellular matrix, enzymes or any other biological materials are subjected to preservation by cooling to very low temperature of- $196^{\circ} \mathrm{C}$ using liquid nitrogen. At this extreme low temperature any enzymatic or chemical activity of the biological material will be totally stopped and this leads to preservation of material in dormant status.

Later these materials can be activated by bringing to room temperature slowly for any experimental work. Protective agents like dimethyl sulphoxide, glycerol or sucrose are added before cryopreservation process. These protective agents are called cryoprotectants, since they protect the cells, or tissues frofn the stress of freezing temperature.

Question 19.
What do you know about Germplasm conservation? Describe it.
Answer:
Germplasm conservation refers to the conservation of living genetic resources like pollen, seeds or tissue of plant material maintained for the purpose of selective plant breeding, preservation in live condition and used for many research works.
Germplasm conservation resources is a part of collection of seeds and pollen that are stored in seed or pollen banks, so as to maintain their viability and fertility for any later use such as hybridization and crop improvement. Germplasm conservation may also involve a gene bank, DNAbank of elite breeding lines of plant resources for the maintenance of biological diversity and also for food security.
Question 20.
Write the protocol for artificial seed preparation.
Answer:

Later these seeds are grown in vitro medium and converted into plantlets. These plantlets require a hardening period (either green house or hardening chamber) and then shifted to normal environment condition.