Chapter 7: Plant Tissue Culture — Online MCQ Test
BIOTECHNOLOGY · Grade 12 · CBSE(NCERT)
Practice Chapter 7: Plant Tissue Culture with a free chapter-wise online MCQ test.
This chapter covers: Plant Tissue Culture Totipotency Callus Micropropagation Aseptic Culture Explants Organogenesis Somatic Embryogenesis Virus Free Plants Crop Improvement.
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter 7: Plant Tissue Culture — Important Questions & Answers
What is totipotency in plant tissue culture?
- A. Ability of a plant cell to develop into a complete plant
- B. Ability of a plant to resist all pathogens
- C. Ability of roots to absorb mineral ions
- D. Ability of pollen grains to germinate on stigma
Answer: A. Ability of a plant cell to develop into a complete plant
Totipotency is the inherent capacity of a living plant cell to regenerate into a complete plant under suitable culture conditions.
Totipotency is the inherent capacity of a living plant cell to regenerate into a complete plant under suitable culture conditions.
The plant part used to initiate a tissue culture is called a/an:
- A. Inoculum
- B. Explant
- C. Scion
- D. Clone
Answer: B. Explant
An explant is a piece of plant tissue or organ taken from a donor plant and used to start an in vitro culture.
An explant is a piece of plant tissue or organ taken from a donor plant and used to start an in vitro culture.
A callus is best described as:
- A. A mature embryo inside a seed
- B. A mass of undifferentiated plant cells
- C. A group of fully developed roots
- D. A specialized vascular tissue
Answer: B. A mass of undifferentiated plant cells
Callus is an unorganized, proliferating mass of undifferentiated cells produced from an explant in culture.
Callus is an unorganized, proliferating mass of undifferentiated cells produced from an explant in culture.
Which condition is essential for successful aseptic plant tissue culture?
- A. Presence of soil particles
- B. Absence of microbial contamination
- C. Direct exposure to open air
- D. Use of non-sterile water
Answer: B. Absence of microbial contamination
Aseptic culture requires sterile conditions so that bacteria and fungi do not overgrow the plant tissue.
Aseptic culture requires sterile conditions so that bacteria and fungi do not overgrow the plant tissue.
In a culture medium, a high auxin to cytokinin ratio generally promotes:
- A. Shoot formation
- B. Root formation
- C. Pollen formation
- D. Seed dormancy
Answer: B. Root formation
The relative concentrations of auxin and cytokinin regulate morphogenesis; higher auxin usually favours root initiation.
The relative concentrations of auxin and cytokinin regulate morphogenesis; higher auxin usually favours root initiation.
Which of the following is NOT a usual step in establishing an aseptic explant culture?
- A. Selection of a healthy explant
- B. Surface sterilization of explant
- C. Inoculation in a sterile medium
- D. Keeping the explant exposed on an open laboratory bench
Answer: D. Keeping the explant exposed on an open laboratory bench
Exposing explants openly increases contamination. Aseptic inoculation is done under sterile conditions such as a laminar airflow cabinet.
Exposing explants openly increases contamination. Aseptic inoculation is done under sterile conditions such as a laminar airflow cabinet.
A leaf explant placed on a medium develops only callus and no roots or shoots. Which change is most likely needed to induce morphogenesis?
- A. Adjust the auxin-cytokinin balance in the medium
- B. Remove all mineral nutrients from the medium
- C. Expose the culture to unsterilized air
- D. Replace sucrose with sand
Answer: A. Adjust the auxin-cytokinin balance in the medium
Organ formation in vitro is strongly influenced by the ratio of auxins and cytokinins, so changing this balance can induce roots or shoots.
Organ formation in vitro is strongly influenced by the ratio of auxins and cytokinins, so changing this balance can induce roots or shoots.
A researcher obtains shoots directly from nodal explants without callus formation. Which conclusion is most appropriate?
- A. The process is direct organogenesis and may help maintain clonal fidelity
- B. The process must be somatic hybridization
- C. The plants produced must be haploid
- D. The explant has undergone fertilization
Answer: A. The process is direct organogenesis and may help maintain clonal fidelity
Direct organogenesis produces organs from the explant without a callus phase, reducing the chance of variation compared with callus-mediated regeneration.
Direct organogenesis produces organs from the explant without a callus phase, reducing the chance of variation compared with callus-mediated regeneration.
A scientist wants to combine nuclear genomes of two sexually incompatible plant species through tissue culture. Which method is most appropriate?
- A. Protoplast fusion followed by regeneration of somatic hybrids
- B. Surface sterilization followed by direct sowing
- C. Meristem culture followed by virus indexing
- D. Hardening followed by self-pollination
Answer: A. Protoplast fusion followed by regeneration of somatic hybrids
Protoplast fusion can combine cells of sexually incompatible species, and regenerated plants are called somatic hybrids.
Protoplast fusion can combine cells of sexually incompatible species, and regenerated plants are called somatic hybrids.
Which combination is most suitable for obtaining true-to-type, virus-free plants of a vegetatively propagated crop?
- A. Meristem culture with careful clonal multiplication
- B. Long-term callus culture with random selection
- C. Anther culture followed by selection of haploids only
- D. Embryo culture after uncontrolled cross-pollination
Answer: A. Meristem culture with careful clonal multiplication
Meristem culture can eliminate viruses, and clonal multiplication helps maintain the genotype of the elite parent plant.
Meristem culture can eliminate viruses, and clonal multiplication helps maintain the genotype of the elite parent plant.