VITEEE: Subject Wise and Full Length VITEEE PCBE Mock Test - 1 Free Online

According to Darwin's theory of evolution, nature selects the fittest. Fitness is based on characteristics which are inherited. Therefore, there must be a genetic basis for getting selected and to evolve. Some organisms are better adapted to survive in an otherwise hostile environment. Adaptative ability is inherited. Fitness is the end result of the ability to adapt and get selected by nature. Therefore, branching descent (inheritance) and natural selection are the two key concepts of Darwin's theory of evolution.

Decomposition is the process that involves the breakdown of complex organic matter or biomass from the body of dead plants and animals with the help of decomposers into inorganic raw materials such as carbon dioxide, water, and other nutrients.

The various processes involved in decomposition are as follows:
➢ Fragmentation 

• It is the first step in the process of decomposition.
• It involves the breakdown of detritus into smaller pieces by the action of detritivores such as earthworms.

➢ Leaching

• It is a process where the water soluble nutrients go down into the soil layers and get locked as unavailable salts.

➢ Catabolism

• It is a process in which bacteria and fungi degrade detritus through various enzymes into smaller pieces.

➢ Humification

• The next step is humification which leads to the formation of a dark-coloured colloidal substance called humus, which acts as reservoir of nutrients for plants.

➢ Mineralization

• The humus is further degraded by the action of microbes, which finally leads to the release of inorganic nutrients into the soil.
• This process of releasing inorganic nutrients from the humus is known as mineralization.

A thorn of Bougainvillea and a tendrill of Curcurbita, both are stem modifications and thus represent homologous structures. The modifications indicate the evolution of the organ to suit different functions which is also known as divergent evolution.

The correct choice is (d):

• (i) polarized

• (ii) positively

• (iii) Na⁺

• (iv) sodium‑potassium pump

• (v) three

• (vi) two

So in resting state the membrane is polarized, with more positive ions outside, an almost‑impermeable barrier to Na⁺, and the Na⁺/K⁺‑ATPase moves 3 Na⁺ out for every 2 K⁺ in.

To evaluate the correctness of the statements:

• Statement i is correct; Hind II was indeed the first restriction endonuclease characterized and it cuts DNA at a specific six-base pair sequence.
• Statement ii is incorrect; the convention for naming these enzymes is the first letter comes from the genus and the next two letters come from the species of the prokaryotic cell from which they were isolated (e.g., EcoRI: E from Escherichia, co from coli).
• Statement iii is incorrect; while exonucleases and endonucleases are both nucleases, not all endonucleases are restriction enzymes. Restriction enzymes specifically cut at defined sequences, while exonucleases remove nucleotides from the ends of DNA.
• Statement iv is correct; restriction endonucleases indeed recognize and cut specific palindromic sequences.
• Thus, the correct options that reflect true statements are i and iv, which corresponds to Option C.

Plasmodesmata are the channels that connect plant cell walls and enable molecular exchange between the cells. They are analogous to gap junctions in animal cells. There are two forms of plasmodesmata; primary ones are formed during cell division and secondary ones can form between mature cells. Plasmodesmata provide a simple route for the movement of ions and macromolecules. Larger molecules use actin filaments to traverse the cells. The middle lamella is a pectin layer which cements the cell walls of two adjoining cells together.

- Statement i is correct because polysaccharides can indeed be classified as homopolymers (like cellulose, which is made only of glucose) or heteropolymers (which contain different types of monosaccharides).

- Statement ii is incorrect; while cellulose is a homopolymer of glucose, it does not form complex helical structures. Instead, it has a linear structure that forms microfibrils.

- Statement iii is correct; starch serves as an energy reserve in plants and forms helical structures that can bind iodine, resulting in a blue complex.

- Statement iv is incorrect; glycogen is a highly branched polysaccharide, not linear, which allows for rapid mobilization of glucose when needed.

Thus, the correct statements are those in Option B: i and iii.

The correct sequences of process of recombinant DNA technology are Isolation of DNA, fragmentation of DNA by restriction endonuclease, isolation of desired DNA fragment, ligation of DNA fragment into vector, transferring of into host and culturing in host cell to get desired product.

Solution: Carbon dioxide is transported in the blood in three main ways: dissolved in plasma, as bicarbonate ions in plasma, and bound to hemoglobin as carbaminohaemoglobin. It does not attach to oxygen molecules for transport. This highlights the body's efficient mechanisms for transporting gases where they need to go.

Statement i) is correct. Lactic acid does accumulate in muscle cells during vigorous exercise when there is insufficient oxygen available to completely break down glucose aerobically. The process by which glucose is converted to lactic acid without oxygen is called anaerobic respiration, which provides energy quickly to the muscles.

Statement ii) is also correct. Since lactic acid is formed by anaerobic respiration, it does not require oxygen. This process is beneficial during intense exercise when the demand for energy is high, but the supply of oxygen is limited.

Statement iii) is incorrect. Oxygen debt (or oxygen deficit) refers to the amount of oxygen required after physical exercise to convert accumulated lactic acid back into glucose and to restore muscle ATP and creatine phosphate levels. This is not about the reduction of oxygen consumption during exercise but rather the additional oxygen required after exercise to recover.

Therefore, the correct answer is B: only statement i) and ii) are correct.

Line in NCERT : Repeated activation of the muscles can lead to the accumulation of lactic acid due to anaerobic breakdown of glycogen in them, causing fatigue.

According to Ohm's law:
V = IR
R =

Dimensional formula of the potential difference is = [M¹L²T^-3A^-1]
Dimensional formula of = = [M¹L³T^-3A^-2]
Or we can say that dimensional formula of conductivity σ = is [M^-1L^-3T³A²]

Using impulse-momentum theorem, we can conclude that, impulse is the change in momentum. Therefore,
[Momentum] = [Impulse]
Hence, the dimensions of both these quantities will be same, i.e., [MLT⁻¹]
Relative density is the ratio of two densities. Hence, relative density is dimensionless.
Also, strain is the ratio of two quantities having same dimensions.
i.e., Strain = Change in length / Original length
Also, power is defined as amount of work done per unit time.
⇒ [ Power ]≠≠[ Work ]

Similarly, 

⇒ 3r + 24 = 4r + 16 ⇒ r = 8Ω

Peptisation is the process of converting a precipitate into a colloidal solution by shaking it with a dispersion medium and a small amount of electrolyte. The red-coloured colloidal solution obtained when dilute HCl is added to ferric hydroxide is an example of peptisation.

Basic strength: I > III > II > IV

The assertion is true: glycerol is purified by distillation under reduced pressure. However, the reason that glycerol is a trihydric alcohol is not the explanation for why it is purified in this way. The reason for reduced pressure distillation is to avoid decomposition into acrolein, a foul-smelling compound.

Formation constant, β₄ = 1/dissociation constant
= = 2.1 x 10¹³

Aldehydes and ketones containing no α-H-atom on reaction with 50% NaOH or KOH, undergo disproportionation to give an alcohol and Na or K salt of an acid. This reaction is called Cannizaro reaction.
Acetaldehyde does not show Cannizaro reaction due to presence of α-hydrogen atom.
Rather, they undergo aldol condensation reaction with dilute base.

Let the numbers be x, x + 2, and x + 4.

Given:
The sum of three consecutive odd numbers is 1383.

x + (x + 2) + (x + 4) = 1383

3x + 6 = 1383

Solving for x:

3x = 1383 - 6

3x = 1377

x = 1377 ÷ 3 = 459

Thus, the three consecutive odd numbers are 459, 461, and 463.

Conclusion: The required largest number is 463.