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

Which one is not property of cancer cells 

  1. They show contact inhibition

  2. Divide in uncontrolled manner

  3. Compete with normal cells for vital nutrients

  4. Do not remain confined to area of formation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. 
  • All cancer cells show the five properties. They are: 
  1. Continuous growth and division. 
  2. Avoidance of programmed cell death. 
  3. Competes with normal cells for vital nutrients.
  4.  Promoting blood vessel construction. 
  5. Invasion of tissue and formation of metastases. Hence, the property which cancer cells does not have is they show contact inhibition.
 So, the correct answer is '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

Proliferation of cancer cells is not limited because of:

  1. Differing surface proteins

  2. Differing cholesterol level

  3. Aberrant chromosomal complement

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

The difference between normal tissues and cancer tissues is the rate of metabolism.  In normal cells, hundreds of genes intricately control the process of cell division. Normal growth requires a balance between the activity of those genes that promote cell proliferation and those that suppress it. However, in the case of cancer cells, they involve abnormal growth. Cells become cancerous after mutations accumulate in the various genes that control cell proliferation. Hence proliferation of cancer cell is not limited because of differing surface proteins and aberrant chromosomal complements. Thus, the correct answer is option D.

Multiple choice general knowledge our skeletal system and the skin other systems in the body introduction to skeletal system busy at work - our internal organs

Consider the following statements:
$1$. Bones and blood are mesodermal in origin.
$2$. Mast cells are modified basophils and secrete heparin.
$3$. Adipose cells store fat.
Which of the statements given are correct?

  1. $1$ and $2$
  2. $2$ and $3$
  3. $1, 2$ and $3$

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

Bones and blood are connective tissues derived from the mesoderm. Mast cells are indeed modified basophils that release heparin and histamine. Adipose cells are specialized for fat storage.

Multiple choice botany plant physiology mineral absorption transport of food, water and minerals mineral transport theories of translocation transport in the phloem of plants

Choose the correct answers from the alternatives given.
An example of selectively permeable membrane is

  1. Plasmalemma

  2. Cell wall

  3. Chloroplast membrane

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

Cell membrane, also known as plasmalemma, is the innermost membrane of a plant cell. It is surrounded by a cell wall. The cell membrane is a selectively permeable membrane that allows only some type of compounds to pass through. The membrane has a phospholipid structure that contributes to this property.

Hence, the correct answer is 'Plasmalemma'.

Multiple choice bio-chemistry the muscular system and digestive system in human beings busy at work - our internal organs skeletal and digestive system from tasting to digestion types of ecological pyramids introduction to human digestive system

Choose the correct answers from the alternatives given.
In Paramecium, the phenomenon of cyclosis is associated with

  1. digestion

  2. excretion

  3. locomotion

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

Cyclosis is the movement in the fluid in the cytoplasm where the proteins and nutrient in the cytoplasm get digested.

So, the correct option is 'digestion'.

Multiple choice biology structural organization in living organisms tissues of plants levels of organisation in plants kinds of plant tissue

Which of the following are the types of simple permanent tissues?

  1. Parenchyma

  2. Sclerenchyma

  3. Collenchyma

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

Simple permanent tissues are simple as they are made up of only one type of cell. They are known as permanent tissue because they have lost the power of division and are specialized. They are classified into three main types parenchyma, sclerenchyma, and collenchyma.

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

Multiple choice botany plant tissues introduction to tissue tissues - "the teams of workers" introduction to tissues

Histology is study of

  1. Tissues

  2. Cells

  3. Structures discernible with naked eyes

  4. Changes in form and structure during development
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

  1. Cytology is the branch of biology that deals with the structure of a cell.
  2. Histology is the branch of biology that deals with the study of microscopic anatomy or tissue.
  3. Morphology is the study of structure discernible with a naked eye.
So the correct option is 'Histology'

Multiple choice botany plant tissues introduction to tissue tissues - "the teams of workers" introduction to tissues

State whether the following statements are true or false.
An extracellular matrix helps some cells to adhere to neighbouring cells.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Extracellular matrix is the network of macromolecules like collagen, enzymes etc, which provide structural support to the cells. They help in the formation of tissues and organs. Extracellular matrix functions as cell adhesive as they are helpful in the interaction between cells and matrix.

So, the correct statement is 'True'.

Multiple choice cancer - causes, signs and diagnosis human health and diseases zoology

Cancer treatment is a difficult process. Which of the following is a reason for it?

  1. Cancer call can undergo uncontrolled division.

  2. Cancer cells adapt and evolve in response to treatment.

  3. Cancer cells become unresponsive to growth signals.

  4. All of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Cancer cells divide uncontrollably and exhibit properties such as loss of contact inhibition and loss of anchorage dependence which can also make them break away from the original site and travel to distant places in the body where they can begin forming a new cancer. This property is called as metastasis. Hence, treatment of cancer is a difficult process. Cancer cells become unresponsive to anti-growth signals which makes them grow uncontrollably.
So, the correct answer is, 'Cancer cell can undergo uncontroled division'.
Multiple choice zoology movement and locomotion in man structure of skeletal muscle muscles and their structure skeletal muscles

An animal cell with numerous nuclei is called

  1. Coenocyte

  2. Syncytial

  3. <p>Plasmodium</p>

  4. Both A and B
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • Syncytial refers to a multinucleate condition where a single cell has more than one nucleus per cell i.e., multiple nuclei with a common cytoplasm.
  • It is caused primarily due to multiple cell fusions of uninuclear cells.
  • This condition usually arises when cells are infected with certain types of viruses (HIV, pneumoviruses etc.).
  • In animals, this condition is seen in skeletal muscles (large skeletal muscle fibres are formed by the fusion of individual muscle cells).
  • So, the correct answer is 'Syncytial'.
Multiple choice biology animal tissue muscular tissues muscle tissue muscle tissues

Among the following, which has the longest group of cells in the body?

  1. Connective

  2. Muscle

  3. Epidermal

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

Muscle tissue is the longest group of cells in the human body. These provide the structural framework to the body. They have contractile proteins which, contracts and relax to provide easy and flexible movements. Therefore, the correct answer is option B.

Multiple choice biology animal tissue muscular tissues muscle tissue muscle tissues

Which of organelle regulates the muscle contraction during internal movements?

  1. Ribosomes

  2. Golgi bodies

  3. Sarcoplasmic reticulum

  4. Both A and B
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Sarcoplasmic reticulum is similar to endoplasmic reticulum present in other cells. It is present in sarcoplasm (cytoplasm of the muscle cell) of the muscle fiber (muscle cell).
  • The main function of the Sarcoplasmic reticulum is to store calcium ions (Ca2+).
  • When nerve signal reaches the neuromuscular junction it triggers the release of calcium from sarcoplasmic reticulum which in turn facilitates muscle contraction by binding to troponin.
  • Hence the organelle regulates the muscle contraction during internal movements is sarcoplasmic reticulum.
  • So, the correct answer is'Sarcoplasmic reticulum'.