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 biology caskets of life observation of cells observing cells cell as structural and functional unit

Which of the following is not present in onion cell?

  1. Nucleus

  2. Chloroplast

  3. Cytoplasm

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

The clear epidermal cells exist in a single layer and do not contain chloroplasts, because the onion fruiting body (bulb) is used for storing energy, not photosynthesis. Each cell has a cell wall, cell membrane, cytoplasm, nucleus and a large vacuole. The nucleus is present at the periphery of the cytoplasm. The vacuole is prominent and present at the centre of the cell, surrounded by cytoplasm. 

Multiple choice biology caskets of life observation of cells observing cells cell as structural and functional unit

A well stained leaf peel preparation when focussed under high power of the microscope would
show :

  1. epidermal cells, stomata and guard cells, each with one nucleus and many chloroplasts.

  2. epidermal cells, stomata and guard cells, each with many nuclei but one chloroplast.

  3. stomata and guard cells without nuclei or chloroplast.

  4. stomata but no guard cells or epidermal cells.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A well-stained leaf peel shows nuclei in a high power microscope. The leaf peel possesses stomata, guard cells and epidermal cells. The nuclei are present in both epidermal and guard cells, but stomata do not possess any nucleus.
So A is the correct option. 
Multiple choice biology caskets of life observation of cells observing cells cell as structural and functional unit

To distinguish microscopically between cheek cell and onion cell mount, one should look for the presence or absence of 

  1. Mitochondria

  2. Plastids

  3. Cell membrane

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

Plastids are double membrane bound organelles found inside plants and some algae, which are primarily responsible for activities related to making and storing food. Many plastids are photosynthetic but some are not.

Therefore, to differentiate between a plant and an animal cell under a microscope, one must look for the presence of plastids.

Multiple choice biology caskets of life observation of cells observing cells cell as structural and functional unit

Geeta was asked to prepare a temporary mount of onion peel and list the steps. While writing, she wrote the following steps, which may not be in proper sequence. The correct sequence would be
(i)   Add a few drops of safranin stain and transfer to a slide.
(ii)  Cover it with a coverslip.
(iii) Add a drop of glycerine.
(iv) Take out onion peel.
(v)  Keep the peel in water in a petri dish.

  1. i, ii, iii, iv, v

  2. iv, v, iii, ii, i

  3. iv, v, i, iii, ii

  4. v, iv, i, iii, ii
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Initially, onion peel has to be taken out.
Then, keep the onion peel in water in a petridish. This will remove the impurities sticked to onion peel. 
Then, add a few drops of safranine stain and transfer to a slide.
Then, add a drop of glycerine on onion peel. This step prevents the peel from drying out. 
Then, cover it with a cover slip for observing it under the microscope and to study the cell pattern. 

Multiple choice botany mineral nutrition in plants deficiency diseases and symptoms deficiency symptoms macronutrients and micronutrients

Which combination of statement is correct?
i. Biosynthesis of nucleorides,proteins and fatty acids takes place in the cytoplasm.
II. Nucleolus is present in the cytoplasm.
iii. Golgi apparatus helps in the forrmation of lysosomes.
iv. Flattened sacs of golgi apparatus is known as cisternae.
v. Ribsomes are not found in prokaryotic cells.

  1. $i,iii \quad and \quad v$
  2. $ii,iii,iv \quad and \quad v$
  3. $i,iii \quad and \quad iv$
  4. $ii,iii \quad and \quad v$

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The biosynthesis of nucleotides, proteins and fatty acids occur in the cytosol of the cell. 

The nucleolus is a dense spheroidal body situated within the nucleus. 
Golgi apparatus stores lysosome enzyme produced by the endoplasmic reticulum and further buds off as small vesicles to develop lysosomes. 

Golgi complex is a membrane-bound organelle that is present in eukaryotic cells that are composed of stacks of flattened and membrane-bound bodies, called cisternae. 
Ribosomes are found in both prokaryotic and eukaryotic cells. 
So, the correct answer is option C. 


Multiple choice botany mineral nutrition in plants deficiency diseases and symptoms deficiency symptoms macronutrients and micronutrients

Apoptosis is programmed cell death characterised by the formation of apoptotic bodies whereas necrosis characterised by bursting of cells. Which of the following condition/s lead/s to necrosis ?
i) Gaps and nicks formed in DNA during replication cannot be repaired.
(ii) Developing neurons fail to make synapses with neighbouring cells.
(iii) Heart muscle cells damaged by oxygen depletion followed by cardiac infarction. 

  1. (i) and (ii)

  2. (ii) and (iii)

  3. (i) only

  4. (iii) only
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Necrosis is accidental cell death resulting from acute injury, trauma, or severe cellular damage, such as oxygen deprivation during a myocardial infarction. In contrast, options (i) and (ii) describe controlled or unaddressed signaling issues typically associated with programmed cell death or apoptosis.

Multiple choice botany living world of animals oviparous and viviparous number and shape of cells unicellular and multicellular organisms diversity and classification in animals

The organism made up of only a single cell is known as 

  1. Unicellular

  2. Acellular

  3. Multicellular

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The cell is the structural unit of life. Unicellular organisms are made up of one cell that performs all the functions and thus, called as a single-celled organism.

Multiple choice evs - i constituents of food dietary sources of proteins types of nutrients calorific value of nutrients

The protein required for the transport of galactose across the cell membrane in E. coli is 

  1. Allolactase
  2. $\beta$-galactosidase

  3. Galactose permease

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

The numerous permeases that belong to ABC superfamily of proteins is present in number of bacterial cell. The ATP is hydrolysed by these proteins  to transport specific amino acids, sugars, vitamins, or even peptides into the cells. One such permease is galactose permease, which is responsible for transportation of galactose.

Multiple choice drug-target interaction pharmaceutical products and drug action medicinal chemistry chemistry in everyday life chemistry body defense system

What is the source of receptor proteins?

  1. Interior of a cell

  2. Cell wall

  3. Out of cell wall

  4. Fixed in the cell membrane partially inside and partially projected outward
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The source of receptor proteins is fixed in the cell wall, partly inside and partly projected out of the cell wall.
This is so that chemical messengers can interact with the outside portion of receptor protein, which transfers the signal to interior of cell via the receptor protein.
Hence, signal is transferred from outside the cell to inside without the messenger having to cross the cell membrane.

Multiple choice biochemical polymers polymerisation chemistry

Maximum amount of RNA is found in:

  1. nucleolus.

  2. chloroplast.

  3. ribosomes.

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

Maximum amount of RNA is present in Nucleolus.

Nucleolus is present in Nucleus.

Multiple choice biology nutrition - food supplying system site of photosynthesis chloroplast and pigments of photosynthesis pigments action spectrum and absorption spectrum spectrum of electromagnetic radiation

Which cellular part is correctly described

  1. Thylakoids - Flattened membranous sacs forming grana

  2. Centrioles - Sites for active RNA synthesis

  3. Ribosomes - Those in chloroplasts are larger (80 S) while those in cytoplasm are smaller (70 S)

  4. Lysosomes - Opimally active at 8.5 pH.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Thylakoids are indeed flattened membranous sacs that stack to form grana. Centrioles are for spindle formation, not RNA synthesis. Chloroplast ribosomes are 70S, not 80S. Lysosomes are acidic (pH 5).

Multiple choice biology photosynthesis site of photosynthesis chloroplast and pigments of photosynthesis pigments action spectrum and absorption spectrum spectrum of electromagnetic radiation

The spaces inside the folds of ER membrane are known as

  1. Thylakoids

  2. Cisternae

  3. Mesosomes

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

The internal flattened sac-like compartments or spaces formed by the folds of the endoplasmic reticulum membrane are known as cisternae. Thylakoids belong to chloroplasts, and mesosomes are infoldings of the plasma membrane in bacteria.

Multiple choice biology nutrition - food supplying system site of photosynthesis chloroplast and pigments of photosynthesis pigments action spectrum and absorption spectrum spectrum of electromagnetic radiation

Match the following

a. Bacteria 1. Synthesis and storage of lipids
b. Sphaerosomes 2. Idiogram
c. Chloroplasts 3. Glycocalyx
d. Karyotype 4. Thylakoids

  1. a-3, b-1, c-4, d-2

  2. a-3, b-1, c-2, d-4

  3. a-4, b-3, c-2, d-1

  4. a-1, b-2, c-3, d-4

  5. a-3, b-2, c-4, d-1.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Bacteria have glycocalyx (a-3). Sphaerosomes are involved in lipid storage (b-1). Chloroplasts contain thylakoids (c-4). Karyotype is represented by an idiogram (d-2).

Multiple choice biology cell structure and micro-organisms animal cell plant and animal cell cell structure

Read the different combinations of terms given below. The correct combination of terms with reference to an animal cell is : 

  1. Cell wall, Cell membrane, Nucleus, Plastid

  2. Cell wall, Nucleus, Ribosome, Chromosome

  3. Cell membrane, Ribosome, Mitochondria, Chromosome

  4. Cell membrane, Ribosome, Mitochondria, Chloroplast
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Animal cells are typical of the eukaryotic cell, enclosed by a plasma membrane and containing a membrane-bound nucleus and organelles like ribosomes, mitochondria etc. 
  • Unlike the eukaryotic cells of plants and fungi, animal cells do not have a cell wall. 
  • Hence, The correct combination of terms with reference to an animal cell is cell membrane, ribosome, mitochondria, chromosome.
  • So, the correct answer is 'cell membrane, ribosome, mitochondria, chromosome'.