Free Cell Structure and Function MCQs with Answers
2,478 Cell Structure and Function MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Animal, plant, prokaryotic and eukaryotic cells are compared through their membranes, cell walls, nuclei and cytoplasmic organelles. The work includes the structures and functions of mitochondria, chloroplasts, ribosomes, endoplasmic reticulum, Golgi apparatus and lysosomes, as well as chromosome organization and the distinction between chromatin and chromosomes.
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Read the Cell Structure and Function notesFree MDCAT chapter notes with key terms2,478 questions · page 105 of 124
- A. Griffith
- B. Watson
- C. Boveri and Sutton
- D. Hershey and Chase
Explanation: Hershey and Chase proved that DNA is a basic genetic material. In 1952, Alfred Hershey and Martha Chase conducted an experiment on…
Correct answer: Hershey and Chase- A. DNA proof-reading
- B. DNA repair
- C. Unwinding
- D. Annealing
Explanation: DNA polymerase enzyme has three types: DNA polymerase-I is involved in proof-reading activities.
Correct answer: DNA proof-reading- A. Attachment of primer
- B. Opening of double helix
- C. Binding of RNA polymerase
- D. Formation of GC hair pin
Explanation: The first step of transcription is the binding of RNA polymerase by using its sigma factor with the promoter region.
Correct answer: Binding of RNA polymerase- A. 4
- B. 16
- C. 8
- D. 64
Explanation: We know that In the genetic code, each codon is made up of three nucleotides.
Correct answer: 8- A. From the 5' toward the 3' end of the new strand being assembled
- B. From the replication centers in two directions called replication forks
- C. From the 3' to the 5' end of the strand being assembled
- D. In both directions if DNA ligase is present
Explanation: DNA polymerase can only add new nucleotides at the 3' end. The process of replication is 5' to 3' at the end of the growing strand.
Correct answer: From the 5' toward the 3' end of the new strand being assembled- A. Small ribosomal subunit
- B. Initiation factor
- C. Elongation factor
- D. Large ribosomal subunit
Explanation: The two amino acids which lie adjacent to each other undergo a chemical reaction, catalyzed by the large ribosomal subunit, which releases…
Correct answer: Large ribosomal subunit- A. DNA and histone protein.
- B. RNA and histone protein.
- C. nitrogenous base and sugar.
- D. nitrogenous base, sugar and phosphate.
Explanation: A nucleosome is the fundamental unit of DNA packaging in eukaryotic cells, consisting of a segment of DNA wound around a core of histone…
Correct answer: DNA and histone protein.- A. Stained darker
- B. Not able to transcribe
- C. Generally not very active
- D. Condensed only during cell division
Explanation: Euchromatin is less condensed compared to heterochromatin and is actively involved in transcription.
Correct answer: Condensed only during cell division- A. I only
- B. III only
- C. I and II
- D. II and III
Explanation: Reduction division, or meiosis, occurs in sexually reproducing organisms to produce gametes with half the chromosome number.
Correct answer: III only- A. Formation of bivalents at the equator
- B. Contraction of the spindle fibres at both poles of the cell
- C. Random orientation of homologous chromosomes at the equator
- D. Dissociation of synaptonemal complex between homologous chromosomes
Explanation: The correct answer is the random orientation of homologous chromosomes at the equator during metaphase-I.
Correct answer: Random orientation of homologous chromosomes at the equator- A. Replication of DNA
- B. Separation of centrioles
- C. Division of centromeres
- D. Formation of chromatids
Explanation: During prophase of the mitotic cell cycle, one of the key processes is the separation of centrioles, which move to opposite poles of the…
Correct answer: Separation of centrioles- A. I and II
- B. III and IV
- C. I, II and III
- D. I, II and IV.
Explanation: In Drosophila melanogaster, the chromosomes are organized into distinct pairs.
Correct answer: I, II and III2093. The given diagram shows the karyotype of a person. The abnormality indicated by this karyotype is:
- A. Klinefelter's syndrome
- B. Turner's syndrome
- C. Down syndrome
- D. Patau's syndrome
Explanation: Option A is correct, as the figure shows an extra X chromosome in the male.
Correct answer: Klinefelter's syndrome- A. Deletion
- B. Inversion
- C. Duplication
- D. Translocation
Explanation: The correct answer is Translocation. In the given diagram, segments of chromosomes are exchanged or moved to a different chromosome, which…
Correct answer: Translocation- A. 3
- B. 6
- C. 9
- D. 12
Explanation: In 2nd meiotic division, sister chromatids separate so chromosome number will remain 6. So option B is correct.
Correct answer: 6- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: During mitosis, sister chromatids separate. During meiosis 1, homologous chromosomes separate.
Correct answer: Option C- A. Two genetically identical chromosomes each
- B. Two genetically different chromosomes each
- C. Four genetically identical chromosomes each
- D. Four genetically different chromosomes each
Explanation: In meiosis, a diploid cell with 8 chromosomes undergoes two rounds of cell division to produce four haploid daughter cells, each…
Correct answer: Four genetically different chromosomes each- A. Chromatin will not condense
- B. The nuclear membrane will not disappear
- C. Centrioles will not move to the opposite poles
- D. Migration of chromatids to the opposite poles will not occur
Explanation: Colchicine is a chemical that disrupts the formation of the spindle fibers necessary for chromatid separation during mitosis.
Correct answer: Migration of chromatids to the opposite poles will not occur- A. Mitosis
- B. Meiosis
- C. S-phase
- D. G2 phase
Explanation: The correct answer is meiosis. Meiosis is characterized by two sequential divisions, meiosis I and meiosis II, which result in a reduction…
Correct answer: Meiosis- A. Primary constriction of a chromosome
- B. Point where two sister chromatids meet
- C. Region of DNA in the middle of a chromosome
- D. Protein complex where spindle fibres are attached
Explanation: The correct answer is Option D. The kinetochore is a protein complex that forms at the centromere of each chromosome and serves as the…
Correct answer: Protein complex where spindle fibres are attached