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The correct answer is Pusa Shubhra

Explanation:

• Plant breeding is the purposeful manipulation of plant species in order to create desired plant types that are better suited for cultivation, give better yields, and are disease-resistant.
• Conventional plant breeding has been practised for thousands of years, since the beginning of human civilization, recorded evidence of plant breeding dates back to 9,000-11,000 years ago.
• Many present-day crops are the result of domestication in ancient times.
• Today, all our major food crops are derived from domesticated varieties.
• Classical plant breeding involves crossing or hybridization of pure lines, followed by artificial selection to produce plants with desirable traits of higher yield, nutrition, and resistance to diseases.
• Resistance to leaf and stripe rust, hill bunt in wheat was transferred and resulted in a new variety called Himgiri.
• Resistance to Chilly mosaic virus, Tobacco mosaic virus, and Leaf curl in chilli was transferred and resulted in a new variety called Pusa Sadabahar.
• Resistance to Black rot and Curl blight black rot in cauliflower was transferred and resulted in a new variety called Pusa Shubhra.
• Better-yielding semidwarf rice varieties Jaya and Ratna were developed in India.

The correct answer is Monascus purpureus

Explanation:

• Statins produced by the yeast Monascus purpureus have been commercialised as blood-cholesterol lowering agents. It acts by competitively inhibiting the enzyme responsible for synthesis of cholesterol.
• Cyclosporin A, that is used as an immunosuppressive agent in organ-transplant patients, is produced by the fungus Trichoderma polysporum.
• Aspergillus niger is known for producing Citric acid.
• Clostridium butylicum is known for producing Butyric acid.

The aorrect answer is Glucose

Explanation:

• Cellulose is a polymer of β-D-glucose monomers. Each monomer is linked to the next by β(1→4) glycosidic bonds.
• This polysaccharide is a major component of the cell walls in plants
• It consists of linear chains of glucose units.

Other Options:

• Maltose: Maltose is a disaccharide composed of two glucose molecules linked by an α(1→4) glycosidic bond. It is produced from the enzymatic breakdown of starch.
• Sucrose: Sucrose is a disaccharide composed of one glucose molecule and one fructose molecule linked by an α(1→2) glycosidic bond. It is commonly known as table sugar.
• Fructose: Fructose is a monosaccharide, also known as fruit sugar. It is found in many plants and is one of the components of sucrose. Its chemical structure is different from glucose, and it is often used in combination with glucose in sweeteners.

The correct answer is Glycosidic bond

Explanation:

• Polysaccharides are carbohydrates consisting of long chains of monosaccharide units bonded together by glycosidic bonds.
• A glycosidic bond is formed between the hydroxyl groups of two monosaccharides through a dehydration reaction, which releases a molecule of water.
• There are two main types of glycosidic bonds: α (alpha) and β (beta), depending on the orientation of the linking oxygen atom in relation to the carbon atoms in the monosaccharides.
• Example: In maltose, two glucose molecules are linked by an α(1→4) glycosidic bond. In cellulose, glucose molecules are linked by β(1→4) glycosidic bonds, contributing to its structural rigidity

Other Options:

• Sulphonic bond: Sulphonic bonds are associated with sulfonic acids and sulfonates.
• Hydrogen bond: While hydrogen bonds can occur between polysaccharide chains and can contribute to the overall structure and stability (e.g., in cellulose), they are not the primary covalent bonds holding the monosaccharides together within the polysaccharide.
• Phosphodiester bond: Phosphodiester bonds are found in nucleic acids (DNA and RNA) and connect the phosphate group of one nucleotide to the hydroxyl group on the sugar of another nucleotide.

The correct answer is Radial

Explanation:

Radial Vascular Bundles: In this arrangement, the xylem and phloem are separated from each other and are arranged alternately along different radii.

• A common example of plants with radial vascular bundles could be seen in roots where the xylem and phloem are arranged in different sectors.
• In the cross-section of a root with a radial arrangement, you might see several "arms" of the xylem alternating with "arms" of the phloem, making a star-shaped pattern in some species.

Conjoint Vascular Bundles: In this arrangement, the phloem and xylem are situated next to each other on the same radius, typically with the phloem located on the exterior (toward the stem surface) and the xylem on the interior. This is the most common type of structural organization in stems and leaves of angiosperms (flowering plants).

When the xylem is surrounded by phloem or phloem is surrounded by xylem, such vascular bundles are known as "Concentric" vascular bundles.

The correct answer is Oxidation

Concept:

• The Calvin Cycle, also known as the C3 cycle, is a series of biochemical redox reactions that take place in the stroma of chloroplasts in photosynthetic organisms.
• This cycle is responsible for the fixation of carbon dioxide and its conversion into glucose, which is a primary source of energy for the plant. For e.g., rice, wheat, oats, barley, cotton, peanuts, etc. are C3 plants.
• The Calvin Cycle consists of three main stages: Carboxylation, Reduction, and Regeneration.

**Explanation:**​

• Carboxylation: This is the first stage of the Calvin Cycle where CO2 is fixed from the atmosphere. It involves the enzyme RuBisCO catalyzing the reaction between CO2 and ribulose-1,5-bisphosphate (RuBP) to form 3-phosphoglycerate. This step does not utilize ATP.
• Reduction: This is the second stage of the Calvin Cycle. In this stage, ATP and NADPH produced during the light reactions are used to convert 3-phosphoglycerate into glyceraldehyde-3-phosphate (G3P). Specifically, ATP provides the energy for the phosphorylation of 3-phosphoglycerate to 1,3-bisphosphoglycerate.
• Regeneration: This is the third stage of the Calvin Cycle. During this stage, ATP is utilized to regenerate ribulose-1,5-bisphosphate (RuBP) from glyceraldehyde-3-phosphate (G3P). This regeneration is essential for the cycle to continue and to ensure that carbon fixation can proceed uninterrupted.

The correct answer is Removal of dust particle from trachea

Explanation: 

• Ciliary movement is characterized by the coordinated, wave-like motions of cilia, which are hair-like structures on the surface of certain cells.
• In the respiratory tract, ciliary movement helps to remove dust and other particles from the trachea by moving mucus up towards the throat where it can be swallowed or expelled. This is an important mechanism for keeping the airways clear.

The correct answer is Leptotene, Zygotene, Pachytene, Diplotene, Diakinesis

Explanation:

Meiosis I is divided into prophase I, metaphase I, anaphase I, and telophase I.

Prophase I of Meiosis I is further divided into - Leptotene, Zygotene, Pachytene, Diplotene, and Diakinesis.

• Leptotene: The chromosomes become gradually visible under the light microscope. The chromosomes start to condense and achieve a compact shape.
• Zygotene: The pairing of homologous chromosomes in zygotene initiates a process called chromosomal synapsis, which is followed by the development of a complex structure known as the synaptonemal complex. The bivalent or tetrad complex is made up of two homologous chromosomes that have synaptically joined.
• Pachytene: During this stage, the four chromatids of each bivalent chromosome become distinct and clearly appear as tetrads. This stage is characterised by the appearance of recombination nodules, the sites at which crossing over occurs between non-sister chromatids of the homologous chromosomes.
• Diplotene: The beginning of diplotene is recognised by the dissolution of the synaptonemal complex and the tendency of the recombined homologous chromosomes of the bivalents to separate from each other except at the sites of crossovers. Chiasmata are the X-shaped structures that occur during separation.
• Diakinesis: Diakinesis is marked by the termination of chiasmata and assembly of the meiotic spindle to separate the homologous chromosomes. The nucleolus disappears and the nuclear envelope breaks down

The correct answer is Phosphoenol pyruvate

Concept:

Different Plants use different photosynthetic processes for atmospheric carbon fixation.

The three main processes are:

C3 cycle - 

• ​In the C3 pathway or Calvin cycle, the primary CO2 acceptor molecule is ribulose bisphosphate (RuBP).
• This reaction is catalysed by the enzyme RuBP carboxylase which results in the formation of two molecules of 3-PGA.

C4 cycle - 

• The primary CO₂ acceptor is 3-carbon molecule phosphoenolpyruvate (PEP) and is present in the mesophyll cells.
• The enzyme responsible for this fixation is PEP carboxylase or PEPcase

CAM pathway - 

• The primary CO2 acceptor is PEP at night, RuBP in the day.
• The enzyme responsible for this fixation is PEPcase at night, Rubisco at daytime.

Explanation:

Phosphoenolpyruvate (PEP):

• PEP is the primary CO₂ acceptor in C4 plants, occurring in the mesophyll cells.
• The enzyme PEP carboxylase catalyzes the fixation of CO₂ to PEP, forming oxaloacetate, which is then converted to malate or aspartate.
• This initial fixation step is highly efficient, even at low CO₂ concentrations, contributing to the high photosynthetic efficiency of C4 plants.

The correct answer is RBCs

Concept:

• Carbon dioxide (CO₂) and oxygen (O₂) are both gases that are transported in the blood, but their solubility in blood plasma differs significantly.
• The solubility of a gas in a liquid is influenced by factors such as temperature, pressure, and the nature of the gas itself.
• CO₂ is more soluble in blood plasma than O₂, which facilitates its transport from tissues to the lungs for exhalation.

Explanation:

• About 97 percent of O₂ is transported by RBCs in the blood. The remaining 3 percent of O₂ is carried in a dissolved state through the plasma.
• Nearly 20-25 percent of CO₂ is transported by RBCs whereas 70 percent of it is carried as bicarbonate. About 7 percent of CO₂ is carried in a dissolved state through plasma.