Biology · Science General

Cell Biology and Structure

3,062 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 botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

Choose the correct answer from the alternatives given:
In which part of the cell is DNA concentrated?

  1. Chromosomes

  2. Cell wall

  3. Ribosomes

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

The chromosomes are the threadlike structures of nucleic acids found in the nucleus of most of the living organisms, carrying the genetic material in the form of genes. Thus DNA is concentrated in the chromosomes.

B. The cell wall is the structural component of the cell that gives shape to the cell.
C. Ribosomes and the Golgi body are the organelles present in the cell. Ribosomes help ion protein synthesis.
D. Golgi apparatus helps to process and bundle macromolecules like proteins and lipids that are synthesized in the cell.
Hence, the correct answer is 'Chromosomes'.

Multiple choice evs identifying the plants absorption of water from the soil root system the root system

Cells of quiescent centre are characterised by

  1. Dense cytoplasm and prominent nuclei

  2. Light cytoplasm and small nuclei

  3. Dividing regularly to add to the corpus

  4. Dividing regularly to add to tunica
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • The quiescent centre or QC is a part of the root-promeristems that contains the initials of epidermis, cortex and stele.
  • The cells here divide less frequently as they are inactive and are present at the pole of cortex and stele.
  • The cells with QC have small dictyosomes, nuclei and nucleoli with little cytoplasm.
  • These cells also have little endoplasmic reticulum, mitochondria and contain low concentrations of RNA, DNA and protein than the other cells of the root apex.
  • So, the correct answer is 'Light cytoplasm and small nuclei'.
Multiple choice evs identifying the plants absorption of water from the soil root system the root system

Root cap regenerated/dead torn cells of root cap are replaced by the activity of

  1. Plerome

  2. Dermatogen

  3. Calyptrogen

  4. Periblem
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Calyptrogen is the formative tissue found in the growing point of a root, giving rise to the root cap. Calyptrogen, as a rule, is characteristic of monocotyledonous plants. In most dicotyledonous plants, instead of calyptrogen, there is a tissue that also gives rise to the root’s absorbent external piliferous layer; this tissue is called dermatocalyptrogen.
The correct option is 'Calyptrogen'.

Multiple choice evs identifying the plants absorption of water from the soil root system the root system

Root region with thin-walled, small cells having sense cytoplasm is

  1. Region of cell elongation

  2. Maturation region

  3. Proximal to cell elongation zone.

  4. Distal to cell elongation zone
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The protoplasm of the cell is surrounded by a primary cell wall which is laid down as the cell begins to grow. It is thin and composed of cellulose, hemicellulose and pectic substances. Once growth has ceased a secondary cell wall may form inside the primary cell wall.

So, the correct option is 'Region of cell elongation'.

Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

The substance which is synthesized in Golgi body is?

  1. Protein

  2. Polysaccharides

  3. Fats

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

The substance which is synthesized in golgi body is polysaccharides. Golgi is a part of the cellular endomembrane system, the Golgi apparatus packages proteins into membrane-bound vesicles inside the cell before the vesicles are sent to their destination. The Golgi apparatus resides at the intersection of the secretory, lysosomal, and endocytic pathways. It is of particular importance in processing proteins for secretion, containing a set of glycosylation enzymes that attach various sugar monomers to proteins as the proteins move through the apparatus.

Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

Carbohydrates, which are present in the cell membrane takes part in which of the following?

  1. Transport of substance.

  2. Cell recognition.

  3. Attachment to microfilament.

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

Carbohydrates which are present in the cell membrane take part in cell recognition. Cell recognition is defined as an active process giving rise to a specific response. 

Cell adhesion is a good example of cell recognition when it can be demonstrated that the adhesion is mediated by molecules having specific binding properties. Such cell adhesion molecules have now been identified in several cellular systems. Carbohydrates, or sugars, are sometimes found attached to proteins or lipids on the outside of a cell membrane. That is, they are only found on the extracellular side of a cell membrane. Together these carbohydrates form the glycocalyx. The glycocalyx of a cell has many functions. It can provide cushioning and protection for the plasma membrane, and it is also important in cell recognition. Based on the structure and types of carbohydrates in the glycocalyx, your body can recognize cells and determine if they should be there or not.

Multiple choice business organisation and correspondence environmental pollution and industries air pollution and its effects the environment and us environment and conservation

Which component of a living cell are affected by the pollutant SO$ _2$ ?

  1. Membrane system of a cell

  2. Wall

  3. Plasmodesmata

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

Sulfur dioxide (SO2) is known to damage plant cells by affecting the membrane system, leading to increased permeability and loss of cellular integrity.

Multiple choice bio-chemistry cell structure and organization eukaryotic cell kinds of cell introduction to eukaryotic cell

Eukaryotic cells have membrane bound organelles.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Organelles are the specialised and organised structures in a living cell. These may be bound by a single or double membrane (Exception is ribosomes which are non-membranous cell organelles present in both prokaryotes and eukaryotes). Membrane-bound cell organelles include nucleus, vacuole, endoplasmic reticulum, chloroplasts, mitochondria, lysosomes, Golgi apparatus and are present only in eukaryotes.
So, the correct answer is 'True'.
Multiple choice bio-chemistry unit of living - cell eukaryotic cell kinds of cell introduction to eukaryotic cell

.......... possesses an organised nucleus with a nuclear envelope.

  1. Prokaryotic

  2. Eukaryotic

  3. Both A and B

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The eukaryotic cell is a cell which contains a membrane-bound nucleus. The nuclear membrane that surrounds nucleus in eukaryotic cells gives the defined structure to the nucleus which consists genetic material. So, the correct answer is option B.
Multiple choice bio-chemistry unit of living - cell eukaryotic cell kinds of cell introduction to eukaryotic cell

 Which of the following types of cell has a well developed cell nucleus?

  1. Prokaryotic

  2. Eukaryotic

  3. Both A and B

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

Eukaryotic cells contain a membrane-bound nucleus. The nuclear membrane that surrounds nucleus in eukaryotic cells gives the defined structure to the nucleus which consists genetic material and thus eukaryotic nucleus is called as well developed nucleus.

Multiple choice bio-chemistry unit of living - cell eukaryotic cell kinds of cell introduction to eukaryotic cell

Which of these cell organelles have double membranes?

  1. Mitochondria

  2. Chloroplast

  3. Nucleus

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

Mitochondria are organelles in cells of eukaryotes. They are double-membraned and the inner membrane forms numerous folds called cristae which extend into the matrix.

The nucleus is surrounded by a nuclear envelope which is double-membraned structure and consists of an outer membrane and an inner membrane that are perforated to allow entry of components into the nucleus.
Chloroplasts are organelles present in plants. They are double-membraned and the inner membrane shows the presence of thylakoids.
Thus the correct answer is option D.

Multiple choice bio-chemistry unit of living - cell eukaryotic cell kinds of cell introduction to eukaryotic cell

Which of the following statements is true for eukaryotic cells?

(i) They have unicellular cells only.
(ii) They have a well-organized nucleus.
(iii) They have lysosomes and peroxisomes.
(iv) Blue-green algae are eukaryotic cells.

  1. ii and iii

  2. ii only

  3. i and ii

  4. i and iv
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Eukaryotic cells contain a well organized, membrane-bound nucleus and organelles (mitochondria, lysosomes, Golgi apparatus) and not found in prokaryotes like bacteria, cyanobacteria. Eukaryotic cells are more complex than prokaryotic cells and are found in a great many different forms. Thus, the correct answer is option A.

Multiple choice bio-chemistry unit of living - cell eukaryotic cell kinds of cell introduction to eukaryotic cell

A cell that is bound solely by a plasma membrane, contains ribosomes, cytoplasm, a nucleus, mitochondria, and Golgi bodies could be characterized as 

  1. Prokaryote

  2. Eukaryote

  3. Fungi

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

Cell organelles like mitochondria, nucleus, Golgi apparatus etc are components of an eukaryotic cell

So, the correct answer is 'Eukaryote'

Multiple choice bio-chemistry unit of living - cell eukaryotic cell kinds of cell introduction to eukaryotic cell

Eukaryotic cells include

  1. Only single envelope system

  2. Prochromosomes

  3. True sap vacuoles

  4. Only 80S ribosomes
Reveal answer Fill a bubble to check yourself
C,D Correct answer
Explanation

  • The eukaryotic cell contains double membrane-bound organelles like mitochondria, Golgi body, lysosomes, etc.
  • Prochromosomes are not present in the eukaryotic cell rather its DNA is linear and condensed to form a structure called chromosomes.
  • True sap vacuoles are present in plant cells they serve as storage of material.
  • The eukaryotic cell contains 80S ribosomes which are made up of two units first one is a small unit (40S) and the second one is a large unit (60S).
So the solution is 'option C  and D.