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 cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

Large cells have a

  1. High metabolic rate.

  2. High respiration rate.

  3. Low surface: volume ratio.

  4. High surface: volume ratio.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

As a cell increases in size, its volume increases much faster than its surface area. This results in a decrease in the surface area to volume ratio, which limits the efficiency of nutrient and waste exchange.

Multiple choice botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

Metabolically active cells have

  1. Lower nucleocytoplasmic ratio.

  2. Higher nucleocytoplasmic ratio.

  3. Higher surface: volume ratio.

  4. Both B and C.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Metabolically active cells require efficient exchange (high surface area to volume ratio) and often have a large nucleus to manage cellular processes (higher nucleocytoplasmic ratio).

Multiple choice botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

Volumes of prokaryotic and eukaryotic cells are ........... respectively.

  1. $0.2-10\mu {m}^{3}$ and $1000-10000\mu {m}^{3}$
  2. $0.1-10\mu {m}^{3}$ and $100-1000\mu {m}^{3}$
  3. $0.1-5.0\mu {m}^{3}$ and $3-30\mu {m}^{3}$
  4. $0.1-1.0\mu {m}^{3}$ and $10-100\mu {m}^{3}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Prokaryotic cells are generally much smaller, typically in the range of 0.2 to 10 cubic micrometers, while eukaryotic cells are significantly larger, ranging from 1000 to 10000 cubic micrometers.

Multiple choice botany cell theory, cell specialization, and cell replacement number and shape of cells unicellular and multicellular organisms diversity and classification in animals

The average volume of a eukaryotic cell is

  1. Between 1 $\mu \, m^3$ and 1,000 $\mu \, m^3$
  2. Between 100 $\mu \, m^3$ and 1,000 $\mu \, m^3$
  3. Between 10 $\mu \, m^3$ and 100 $\mu \, m^3$
  4. Generally greater than 10,000 $\mu \, m^3$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A cell of 1 μm^3 volume average to the maximum 1,000 μm^3 most highly expressed proteins in a cell.

So, the correct option is 'Between 1 μm^3 and 1,000 μm^3'.

Multiple choice zoology skeleton and movements introduction to movement introduction to locomotion movement

Taxis is movement in

  1. Single cell

  2. Single-celled organism

  3. Cell organelles

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

Taxis is a kind of behavioural response of a cell, cell organelles or an organism to an external stimulus such as light or food. It is the orientation of an organism or a cell in a specific spatial relationship to a stimuli. If the movement is towards the stimuli it is positive taxis and if it is away from the stimuli it is negative taxis. 

Thus, the correct answer is option D. 

Multiple choice bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

Which tissue is responsible for providing insulation to the body?

  1. Epithelial tissue

  2. Adipose tissue

  3. Fibrous connective tissue

  4. Nervous tissue

  5. Muscle tissue
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Adipose tissue, or fat, is an anatomical term for loose connective tissue composed of adipocytes. Its main role is to store energy in the form of fat, although it also cushions and insulates the body.

Multiple choice zoology important and common human diseases diseases caused by changes in lifestyle diseases and toxic substance non-infectious diseases

Which one of the following in not a feature of cancerous cells?

  1. They divide in an uncontrolled manner.

  2. They do not remain confined to one localized area.

  3. They compete with normal cells for vital nutrients.

  4. They show contact inhibition.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cancer is a group of disease, that involves abnormal cell growth (abnormal cell division), with the potential to invade or spread to other parts of the body. They compete with normal cells for nutrients. Contact inhibition is a growth mechanism, which functions to keep cells growing into a layer one cell thick or monolayer. The cancer cells do not show contact inhibition and they grow uncontrollably.
Thus, the correct answer is option (D), 'They show contact inhibition'.

Multiple choice zoology important and common human diseases diseases caused by changes in lifestyle diseases and toxic substance non-infectious diseases

HeLa cells used in cell biology are

  1. Cancerous cells grown in cancer research laboratory

  2. Cervial cancer cell derivatives

  3. Both A and B

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

  • HeLa cells are the cell type in immortal cell lines used in scientific research. It is the oldest and most commonly used human cell line.
  • The line was derived from cervical cancer cells taken on February 8, 1951, from Henrietta Lacks, a patient who died of her cancer on October 4, 1951.  These cells are grown in a laboratory and are used for conducting many experiments.
Thus, the correct answer is option C.

Multiple choice zoology important and common human diseases diseases caused by changes in lifestyle diseases and toxic substance non-infectious diseases

Cancer cells are characterized by

  1. Uncontrolled growth

  2. Invasion of local tissue

  3. Spreading to other body parts

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

Cancer is a group of diseases involving the abnormal cell growth where there is invasion of the local tissue and there is a potential to invade or spread to other body parts .
Therefore, the correct answer is option D.

Multiple choice zoology important and common human diseases diseases caused by changes in lifestyle diseases and toxic substance non-infectious diseases

Which one of the following is not a property of cancerous cells?

  1. They compete with normal cells for vital nutrients.

  2. They do not remain confined in the area of formation.

  3. They divide in an uncontrolled manner.

  4. They show contact inhibition.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

During tumorigenesis, cancerous cells undergo rapid cell division and compete with normal cells for nutrients.
Cancer cells spread to other parts of the body, a process called metastastize i.e., are not confined in area  of formation.
Cancer is the result of cells that uncontrollably grow and do not die.
So, statements A, B and C are correct.
Normal cells when grown in culture, will become growth inhibited, when they encounter another cell. This is contact inhibition and Cancer cells show no contact inhibition as they do not stop dividing and keep growing.
Thus, the correct answer is option (D), 'They show contact inhibition'.

Multiple choice zoology important and common human diseases diseases caused by changes in lifestyle diseases and toxic substance non-infectious diseases

................. is the process by which cancer cells spread from one region of the body to other 

  1. Hypostasis

  2. Metastasis

  3. Parastasis

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

Metastasis is the movement of spreading of cancer cells from one organ or tissue to another. Cancer cells usually spread through the blood or the lymph system. It is mainly caused due to the mutagens which cause a sudden heritable change in the DNA content which leads to fatal abnormalities.
So, the correct answer is option B.

Multiple choice zoology important and common human diseases diseases caused by changes in lifestyle diseases and toxic substance non-infectious diseases

Cancer cells are characterised by 

  1. Uncontrolled growth

  2. Spreading to the other body part

  3. Invasion of local tissue

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

Cancer cells are cells that divide rapidly, forming solid tumours or flooding the blood with abnormal cells. Malignant cancerous cells spread from their initial site to other organs or tissues resulting in metastasis. Cancer cells undergo invasion of local tissue i.e., direct extension and penetration by cancer cells into neighbouring tissues. Hence, cancer cells are characterised by uncontrolled growth, spreading to other body part and invasion of local tissue.

So, the correct answer is 'All of the above'.

Multiple choice zoology important and common human diseases diseases caused by changes in lifestyle diseases and toxic substance non-infectious diseases

Transformation of a normal cell to cancer cell may start with changes in 

  1. Cytoplasm

  2. Nucleus

  3. Mitochondria

  4. Fibronetin
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • A gene is the basic physical and functional unit of heredity. Genes are made up of DNA and DNA is present inside the nucleus.
  • Mutations in genes can cause cancer by accelerating cell division rates or inhibiting normal controls on the system, such as cell cycle arrest or programmed cell death. As a mass of cancerous cells grows, it can develop into a tumour.
  • Hence Transformation of a normal cell to cancer cell may start with changes in  Nucleus.
  • So, the correct answer is 'Nucleus'.