CUET 2026 Biology May 18 Shift 1 Question Paper- Download Answer Key and Solution PDF

In the recombinant DNA technology involving plasmid pBR322, insertion of foreign DNA at the PstI restriction site results in the loss of resistance against:

• (A) Tetracycline
• (B) Ampicillin
• (C) Chloramphenicol
• (D) Kanamycin

Which scientist experimentally demonstrated that DNA replication is semiconservative in nature using \(^ {15}N\) and \(^ {14}N\) isotopes?

• (A) Watson and Crick
• (B) Meselson and Stahl
• (C) Hershey and Chase
• (D) Griffith

The correct evolutionary sequence in the evolution of modern humans is:

• (A) Homo habilis \(\rightarrow\) Homo erectus \(\rightarrow\) Neanderthal man \(\rightarrow\) Cro-Magnon man
• (B) Homo erectus \(\rightarrow\) Homo habilis \(\rightarrow\) Neanderthal man
• (C) Neanderthal man \(\rightarrow\) Homo habilis \(\rightarrow\) Cro-Magnon man
• (D) Cro-Magnon man \(\rightarrow\) Homo erectus \(\rightarrow\) Homo habilis

Match the following mammals with their correct category and geographical distribution.

Choose the correct option.

• (A) \(P \rightarrow 2,\ Q \rightarrow 1,\ R \rightarrow 3,\ S \rightarrow 4\)
• (B) \(P \rightarrow 1,\ Q \rightarrow 2,\ R \rightarrow 3,\ S \rightarrow 4\)
• (C) \(P \rightarrow 2,\ Q \rightarrow 4,\ R \rightarrow 1,\ S \rightarrow 3\)
• (D) \(P \rightarrow 3,\ Q \rightarrow 1,\ R \rightarrow 2,\ S \rightarrow 4\)

A bioreactor working for industrial production of antibiotics must maintain maximum microbial growth and product formation. Which combination of components is correctly matched with their functions?

Choose the correct option.

• (A) \(P \rightarrow 1,\ Q \rightarrow 2,\ R \rightarrow 3,\ S \rightarrow 4\)
• (B) \(P \rightarrow 2,\ Q \rightarrow 1,\ R \rightarrow 4,\ S \rightarrow 3\)
• (C) \(P \rightarrow 3,\ Q \rightarrow 2,\ R \rightarrow 1,\ S \rightarrow 4\)
• (D) \(P \rightarrow 1,\ Q \rightarrow 4,\ R \rightarrow 2,\ S \rightarrow 3\)

Read the following statements carefully regarding scientists and their contributions in genetics.


[(P)] Mendel proposed the law of segregation.
[(Q)] Sutton and Boveri proposed chromosomal theory of inheritance.
[(R)] T.H. Morgan experimentally proved linkage in \textit{Drosophila.
[(S)] Hershey and Chase proved that proteins are genetic material.


Choose the correct option.

• (A) P, Q and R are correct but S is incorrect
• (B) P and R are correct but Q and S are incorrect
• (C) Only P and Q are correct
• (D) All statements are correct

Which hormone is secreted by the corpus luteum during pregnancy?

• (A) Estrogen only
• (B) Progesterone only
• (C) Progesterone and relaxin
• (D) Testosterone

Read the following statements regarding Bt cotton and choose the correct option.


[(P)] Bt toxin is produced by \textit{Bacillus thuringiensis.
[(Q)] The inactive protoxin gets activated in the acidic gut of insects.
[(R)] Cry proteins create pores in the epithelial cells of insect midgut.
[(S)] Different cry genes control different groups of insects.

• (A) P, R and S are correct but Q is incorrect
• (B) P and Q are correct but R and S are incorrect
• (C) Only P and R are correct
• (D) All statements are correct

Match the following mammals in List-I with their correct characteristics in List-II.

Choose the correct option.

• (A) \(P \rightarrow 3,\ Q \rightarrow 4,\ R \rightarrow 2,\ S \rightarrow 1\)
• (B) \(P \rightarrow 1,\ Q \rightarrow 3,\ R \rightarrow 2,\ S \rightarrow 4\)
• (C) \(P \rightarrow 3,\ Q \rightarrow 1,\ R \rightarrow 4,\ S \rightarrow 2\)
• (D) \(P \rightarrow 2,\ Q \rightarrow 1,\ R \rightarrow 3,\ S \rightarrow 4\)

During transcription in eukaryotes, the enzyme responsible for synthesis of mRNA is:

• (A) DNA polymerase
• (B) RNA polymerase I
• (C) RNA polymerase II
• (D) RNA polymerase III