Biology · Science General

Cell Biology and Structure

3,221 Questions

Cell biology focuses on the structure and function of cellular organelles. Key topics include cellular respiration, DNA inheritance, and energy production. These fundamental biology concepts are crucial for medical entrance and state service examinations.

Cell organelles functionsCellular respiration sitesDNA and ribosomesAnimal cell structurePlant cell components

Cell Biology and Structure Questions

Multiple choice

Double membrane is absent in _____.

  1. chloroplast

  2. lysosome

  3. nucleus

  4. mitochondria
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Lysosomes are single-membrane-bound organelles containing digestive enzymes. Mitochondria, chloroplasts, and the nucleus are all surrounded by a double membrane.

Multiple choice

_____ is called false foot.

  1. Pseudoartistic

  2. Pseudocarp

  3. Pseudopodium

  4. Pseudobranch
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Pseudopodia (singular: pseudopodium) are temporary protrusions of the cytoplasm used by amoeboid cells for movement and feeding, literally meaning 'false feet'.

Multiple choice

Which of the following statements are TRUE regarding prokaryotic cell? P. Prokaryotic cells are larger in size than eukaryotic cells. Q. Lysosomes are present. R. Site for oxidative phosphorylation is cell membrane. S. Ribosomal subunits are 50S and 30S.

  1. Only P and Q

  2. Only P and S

  3. Only Q and R

  4. Only Q and S

  5. Only R and S
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Yes, both are true. Site for oxidative phosphorylation in prokaryotic cells is cell membrane. Cytoplasmic ribosome size of prokaryotic cells is 70S. Ribosomal subunits are 50S and 30S.

Multiple choice

Match the entries in List I (Cell organelle) and List II (Discoverer)

 
List - I
List - II
P. Chondriosomes 1. R. Altman
Q. Centrosome 2. Edouard Van Beneden
R. Microtubules 3. De Robertis and Franchi
S. Vacuoles 4. Antony van Leeuwenhoek

  1. P - 1, Q - 2, R - 3, S - 4

  2. P - 2, Q - 1, R - 4, S - 3

  3. P - 2, Q - 3, R - 4, S - 1

  4. P - 3, Q - 2, R - 4, S - 1

  5. P - 4, Q - 2, R - 3, S - 1
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Yes, it is correct. Mitochondria, at times referred to as chondriosomes, were discovered by R. Altman. Centrosome was discovered by Edouard Van Beneden. Microtubules were first discovered by De Robertis and Franchi. Vacuoles are believed to have been discovered by Antony van Leeuwenhoek.

Multiple choice

Which of the following statements is/are FALSE regarding mitochondria?

  1. Mitochondria are a cell organelle which has electrons transport system.
  2. Synthesis of ATP in mitochondria takes place at the cristae.
  3. The enzymes for Kreb’s cycle in mitochondria are located in perimitochondrial space.

  1. Only 1

  2. Only 2

  3. Only 3

  4. Only 1and 2

  5. Only 2 and 3
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

It is a correct answer, as statement 3 is false. The enzymes for Kreb’s cycle in mitochondria are located in mitochondrial matrix.

Multiple choice

Which of the following is a set of single membrane bounded organelles?

  1. Ribosome, Nucleolus, and Chromosome

  2. Ribosome, Nucleolus, and Lysosome

  3. Nucleolus, Endoplasmic Reticulum, and Golgi complex

  4. Lysosome, Ribosome and Chromosome

  5. Endoplasmic Reticulum, Golgi complex, and Lysosome
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Endoplasmic Reticulum, Golgi complex, and Lysosome, all are single membrane bounded organelles.

Multiple choice

Arrange the following in correct sequence of signal transduction pathway:

  1. Hormone
  2. 7 TM receptor
  3. G protein
  4. cAMP
  5. PKA

  1. 1 → 2 → 3 → 4 → 5

  2. 1 → 3 → 2 → 4 → 5

  3. 1 → 4 → 3 → 2 → 5

  4. 5 → 2 → 3 → 4 → 1

  5. 5 → 4 → 3 → 2 → 1
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Correct answer. Correct sequence of signal transduction pathway is Hormone → 7 TM receptor → G protein → cAMP → PKA. In the G protein associated signal cascade system, binding of hormone to a cell surface receptor, like the 7TM (a 7 transmembrane alpha helices) which is a part of G protein. This will activate production of second messengers like cAMP by the enzyme adenylate cyclase. The cAMP in turn binds and activates downstream signal proteins line cAMP dependent protein kinase A (PKA).

Multiple choice

Match the column – I (structures of cells) with column – II (relative functions) and select the correct option.

 
Column – I
Column – II
A. Cytoplasmic membrane 1. Mineral storage of cells
B. Ribosome 2. Protein synthesis
C. Inclusion body 3. Tough, heat resistance structure that helps bacteria survive in adverse conditions
D. Endospore 4. Regulation of substance transport into and out of cells

  1. A - 1, B - 2, C - 3, D - 4

  2. A - 2, B - 1, C - 4, D - 3

  3. A - 4, B - 2, C - 1, D - 3

  4. A - 3, B - 2, C - 4, D - 1

  5. A - 4, B - 3, C - 2, D - 1
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Correct answer. The cell membrane (also known as the plasma membrane or cytoplasmic membrane) is a biological membrane that separates the interior of all cells from the outside environment. The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells Ribosomes are small, electron-dense particles not enclosed in membrane and are located in the cytosol. Ribosomes are involved in protein synthesis. Inclusion bodies are the transitory residents of the cytoplasm not involved in cell metabolism and do not survive cell division. They comprise mainly accumulated metabolites, lipid droplets and pigments and are sporadically distributed in body cells. An endospore is dormant, tough, and non-reproductive structures produced by certain bacteria from the Firmicute phylum, that help bacteria survive in adverse conditions.