Strategies For Enhancement In Food Production

A protoplast is a cell without a cell wall that is composed of cytoplasm, plasma membrane, and cell organelles.

• The cell wall is removed by the action of enzymes.
• Cellulase enzymes digest cellulose present in plant cell walls.
• Pectinase enzymes break down the cells that hold pectin together. 
• Once, the cell wall is removed, the protoplast becomes spherical in shape.

Hence, option B) without cell wall is the correct answer.

TERMS USED IN THE QUESTION:

1. Telophase: The final stage of cell division, where chromosomes have reached opposite poles of the cell and begin to decondense.
2. Cell plate: As we are observing a plant cell, a cell plate is a structure that forms during cytokinesis (the division of the cytoplasm), which will eventually become the new cell wall of the daughter cells.

TERM USED IN THE ANSWER:

1. Polyploidy: Polyploidy is a condition where cells have multiple sets of chromosomes.

• In plant cells, division typically involves the formation of a cell plate to create a new cell wall.
• Now, in our case, cell plate formation doesn’t occur, which suggests that cytokinesis wasn't complete.
• Due to this, the cell ends up with double the normal number of chromosomes. This condition is called polyploidy.

True Breeding Line

A true breeding line is one that, having undergone continuous self-pollination, exhibits stable trait inheritance and expression over several generations. In genetics, a true breeding line refers to organisms that consistently pass on the same traits to their offspring, ensuring that the traits are maintained through generations.

This stability of inheritance occurs because the organisms are homozygous for the trait in question. Homozygosity means that both alleles for a particular gene are the same, whether they are dominant or recessive. A true breeding line can be homozygous dominant (e.g., TT) or homozygous recessive (e.g., tt), depending on the trait being studied.

Key Points:

• The organism has undergone continuous self-pollination.
• The trait inheritance and expression remain stable over several generations.
• It can be homozygous dominant or homozygous recessive.

In summary, a true breeding line is a genetic line that, through generations of self-pollination, consistently exhibits the same trait expression, either dominant or recessive, due to homozygosity for the trait.

• Biomagnification: This refers to the process by which the concentration of toxic substances increases in organisms at higher trophic levels in a food chain. It is unrelated to improving nutrient content in crops.
• Bioremediation: A process used to treat contaminated media, including water and soil, by promoting the growth of microorganisms that degrade pollutants. It does not pertain to enhancing crop nutrition.
• Biofortification: The actual process of increasing the nutritional value of crops through biological methods, including traditional breeding.
• Bioaccumulation: This involves the accumulation of substances, such as pesticides, or other chemicals in an organism. It is associated with environmental sciences rather than crop nutrient enhancement.

• Exposes harmful recessive genes that are eliminated by selection: Inbreeding can lead to the expression of recessive alleles, some of which may be harmful. Once expressed, these harmful genes can be targeted and eliminated through selective breeding.
• Elimination of less desirable genes and accumulation of superior genes: This is one of the benefits of inbreeding, as it can help in fixing desired traits and accumulating beneficial genes over generations.
• Decreases the productivity of inbred population, after continuous inbreeding: One of the drawbacks of inbreeding is inbreeding depression, which can reduce the overall fitness and productivity of a population due to the increased expression of recessive deleterious alleles.
• Decreases homozygosity: Inbreeding actually increases homozygosity because mating between genetically similar individuals results in offspring with more homozygous gene pairs.