All Free Biology MCQs with Answers

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19844 questions · page 673 of 1985

6721. Which of the following is not the function of cell membrane?

Moderate
  • A. Protection of cytoplasm
  • B. Regulating the passage of different molecules
  • C. Protein synthesis
  • D. Cellular communication
  • E. Cellular transportation

Explanation: Protein synthesis is the function of ribosomes.

Correct answer: Protein synthesis

6722. When plant cell receives a signal for death, it commits suicide by rupturing:

Moderate
  • A. Nucleus
  • B. Cell membrane
  • C. Tonoplast
  • D. Chloroplast

Explanation: Tonoplast is the membrane of vacuole found in the center of plant cell, when its membrane breaks, the cell ultimately shrinks or ruptured.

Correct answer: Tonoplast

6723. An enzyme that is attached to cell membrane of cell:

Moderate
  • A. Adenylate cyclase
  • B. Cytochrome oxidase
  • C. Succinate dehydrogenase
  • D. Glucokinase

Explanation: This enzyme is attached with cell membrane of cell and it converts ATP into cyclic AMP.

Correct answer: Adenylate cyclase

6724. Which of the following is not associated with both prokaryotic and eukaryotic cell membrane?

Moderate
  • A. Receptors
  • B. Enzymes
  • C. DNA replication
  • D. Antigens

Explanation: Receptors, enzymes and antigens all are found in both prokaryotic and eukaryotic cell meinbrane. However, only prokaryotic cell membrane is associated with DNA replication.

Correct answer: DNA replication

6725. Peripheral parts of the cell are often like:

Moderate
  • A. Sol
  • B. Gel
  • C. Solid
  • D. None of these

Explanation: Consistency of cytoplasm is both like sol and gel, but peripheral part is more gel like while central is sol like.

Correct answer: Gel

6726. It is false about cytoplasm of eukaryotic cell:

Moderate
  • A. Glycolysis
  • B. Transcription
  • C. Site of glycogen storage
  • D. Translation

Explanation: Cytoplasm is a site for many important biochemical reactions such as glycolysis, protein synthesis etc. in both prokaryotic and eukaryotic cells. Transcription in eukaryotic cell takes place in nucleus.

Correct answer: Transcription

6727. 40S is the smaller ribosomal sub-unit, associated with_.

Moderate
  • A. E. coli
  • B. Yeast
  • C. C. botulinum
  • D. T. pallidum

Explanation: E. coli. C. botulinum and T. pallidum are prokaryotic organisins having 30S smaller ribosomal subunit, while yeast is eukaryotic organism having 40S smaller ribosomal subunit and 60S larger sub-unit.

Correct answer: Yeast

6728. The cytoplasmic organelle commonly found both in prokaryotes and eukaryotes is:

Moderate
  • A. Flagellum
  • B. Ribosome
  • C. Mitochondria
  • D. Nucleoid

Explanation: Presence of ribosomes is one of the common features between prokaryotic and eukaryotic cells.

Correct answer: Ribosome

6729. 70S sized ribosomes are found in the cells of:

Moderate
  • A. Algae
  • B. Protozoans
  • C. Fungi
  • D. Bacteria

Explanation: There are two types of ribosomes in living world. Smaller is 70S that is present in prokaryotes.

Correct answer: Bacteria

6730. Which of the following is true about cytoplasm?

Moderate
  • A. It can exist only in gel form
  • B. It is the region between nucleus and cell membrane
  • C. 70% of the cytoplasm is water
  • D. Both prokaryotes and eukaryotes show cyclosis.

Explanation: Cytoplasm is the region between nucleus and cell membrane. It has both cytosol and cytogel. About 90% of cytoplasm is water. Cyclosis is a feature of eukaryotic cells.

Correct answer: It is the region between nucleus and cell membrane