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 movement in and out of the cell transport of molecules osmosis and plasmolysis plant water relation

Which one of the following is the correct statement for an active sodium-potassium ATPase ?

  1. It pumps out 3 Na-ions and pumps in 2 K-ions

  2. It pumps out 3 Na-ions and pumps in 3 K-ions

  3. It pumps out 3 Ca-ions and pumps in 2 K-ions

  4. It pumps out 3 Na-ions and pumps in 2 Ca-ions
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Sodium-potassium pump is important to produce action potential by nerve cells. As it transport of three Na+ to the outside of the cell and the transport of two K+ ions to the inside. This changes the membrane potential on the inside, making the inside of the cell more negative or hyperpolarized, which leads to forward movement of electric impulse

So, the correct answer is 'It pumps out 3 Na$^+$and pumps in 2 K$^+$ '

Multiple choice evs - i constituents of food minerals in our diets types of nutrients nutrients and deficiency

Which vitamins are present in much smaller amounts in cells?

  1. $A$
  2. $D$
  3. $B $ and $C$
  4. $K$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Vitamins $B$ and $C$ are present in much smaller amounts in cells. These vitamins are micronutrients. These are required in very minute amounts. Together, they are extremely important for the normal functioning of the body. Their main function is to enable the many chemical reactions to occur in the body.

Multiple choice zoology living and non living characteristics of life attributes of living organisms signs of life biology : an introduction living world and classification

Characteristics of living things are

  1. Made up of cells

  2. Growth

  3. Response

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

All living things and dead are made up of the cells which perform life processes for maintaining life. They give the response to the stimulus or environmental factors. But growth is the characteristic of both living and dead as dead like wood shows growth by the absorption of water. Thus, the growth is the characteristics of living things but not the defining or fundamental properties of living things. Hence, the correct answer is option D.

Multiple choice zoology living and non living characteristics of life attributes of living organisms signs of life biology : an introduction living world and classification

The structural unit of a non-living thing is

  1. Electron

  2. Neuron

  3. Cell

  4. Molecule
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Electron is a stable sub-atomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids. 

Molecule is a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction. 
Cell is the structural unit of a living being.  
A neuron is an electrically excitable cell that processes and transmits information through electrical and chemical signals. 

Multiple choice zoology living and non living characteristics of life attributes of living organisms signs of life biology : an introduction living world and classification

Both living things and nonliving things are made of 

  1. Cells

  2. Molecules

  3. Tissues

  4. Organs
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Every living being is composed of cells which act as the basic structural unit. these cells are in turn made up of more simpler molecules like amino acids, sugars. And all non- living things are also made up of repetitive sequence or mixing of one or more types of molecules.
Hence the correct option is B.
Multiple choice zoology living and non living characteristics of life attributes of living organisms signs of life biology : an introduction living world and classification

Cellular organization has ______ stages

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

The components of the cell and the arrangement of the individual parts within the cell form the cellular organisation. There are five stages which include cell, tissue, organs, organ systems and organisms. The cellular organisation provides the complete about the working model of the cell and its components.

So, the correct option is '5'.

Multiple choice evs transportation in living organisms circulatory system and organs blood and blood vessels circulatory system blood pressure

Which of the following statement is true ?

  1. Vessels are multicellular with narrow lumen

  2. Tracheids are multicellular with narrow lumen

  3. vessels are unicellular with narrow lumen

  4. Tracheids are unicellular with wide lumen
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Vessels are multicellular structures formed by the fusion of several cells, and they have a relatively narrow lumen compared to the overall plant structure, though they are wider than tracheids.

Multiple choice zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

Feulgen test, is unique for DNA, is a

  1. Gentian violet

  2. Neutral red

  3. Basic fuchsin

  4. Cotton blue
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • The feulgen test is a staining technique discovered by Robert Feulgen and used in histology to identify chromosomal material or DNA in cell specimens.
  • The Feulgen test, is unique for DNA, is a Basic Fuchsin.
  • It is used for demonstration of DNA (deoxyribonucleic acid) in tissue sections. 
  • So, the correct answer is 'Basic fuchsin',   
Multiple choice structure of dna and rna nucleic acids and polynucleotides nucleic acids and protein synthesis molecular biology biology

In eukaryotes basic structural unit made of histone and DNA 

  1. Nucleosome

  2. Nucleolus

  3. Chromosome

  4. Lysosome
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In eukaryotes DNA is tightly bound to histones which form a DNA protein particles called nucleosome. Each nucleosome contains 2 copies of each $H _{2A},H _{2B}.H _{3}$ and $H _{4}$ histone protein bounded on 146 BP of DNA.Each nucleosome bead is linked to next nucleosome bead by linker DNA.

Multiple choice biology protectors of biosphere structure of chloroplast plastids photosynthetic pigments

The factory for synthesis of sugars in autotrophic eukaryotes is

  1. Chloroplast

  2. Mitochondrion

  3. Endoplasmic reticulum

  4. Ribosome
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chloroplasts are the cell organelles where photosynthesis occurs. The light reactions occur in thylakoid membranes and dark reactions occur in stroma of chloroplasts. These reactions result in synthesis of sugars (glucose) in chloroplasts.

Multiple choice biology protectors of biosphere structure of chloroplast plastids photosynthetic pigments

From the following, an organelle containing chlorophyll is

  1. Chloroplast

  2. Endoplasmic reticulum

  3. Nucleus

  4. Mitochondria
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A. Chloroplasts are greenish plastids which possess photosynthetic pigments, chlorophylls and carotenoids and take part in the synthesis of food. Chlorophylls contain specialised light-absorbing green pigments, therefore help in photosynthesis.
B. Endoplasmic reticulum is a network of reticulum of tiny structures scattered in cytoplasm and composed of three structures- cisternae, tubules and vesicles.
C. Nucleus is a large organelle controlling all the activities of the eukaryotic cells and consists of nuclear envelope, nucleoplasm, nucleolus and chromatin.
D. Mitochondria are cylindrical double membrane organelles and composed of outer, inner membrane, crista and matrix.
So, the correct answer is 'Chloroplast'.
Multiple choice biology protectors of biosphere structure of chloroplast plastids photosynthetic pigments

Which of the following is not characterized as an organelle?

  1. Nucleus

  2. Golgi apparatus

  3. Lysosome

  4. Chlorophyll

  5. Chloroplast
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The eukaryotic cell also possesses several membrane-bound organelles. The cell is composed of the nucleus, Golgi complex, lysosome, chloroplast, mitochondria, etc. Chlorophyll is the coloured pigment inside the chloroplast which is involved in the process of photosynthesis.

Thus, the correct answer is option 'Chlorophyll'.

Multiple choice biology protectors of biosphere structure of chloroplast plastids photosynthetic pigments

Which of the following organelle acts as a site for photosynthesis in plants?

  1. Ribosome

  2. Mitochondria

  3. Chloroplast

  4. Endoplasmic reticulum

  5. Golgi apparatus
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The process of photosynthesis takes place in the chloroplasts, using chlorophyll, the green pigment involved in photosynthesis. Chloroplasts absorb sunlight and use it in conjunction with water and carbon dioxide gas to produce food for the plant. Chloroplasts capture light energy from the sun to produce the free energy stored in ATP and NADPH through a process called photosynthesis.