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 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 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 internal structure of root, stem and leaf internal structure of monocot leaf internal structure of leaf (dicot and monocot) anatomy of leaf

Cells which help in rolling and unrolling of leaf lamina in grasses are 

  1. Complementary cells

  2. Motor cells

  3. Passage cells

  4. Companion cells
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • The leaves of monocots have a large bubble-shaped epidermal cell called bulliform cells.
  • They are also known as motor cells.
  • They are present in the adaxial surface of the leaves.
  • They play an important role in the unfolding of the developing leaves and in the rolling and unrolling of mature leaves in response to the alternating wet and dry conditions.
  • So, the correct answer is 'Motor cells'.
Multiple choice botany internal structure of root, stem and leaf internal structure of monocot leaf internal structure of leaf (dicot and monocot) anatomy of leaf

The number of types of cells presents in the adaxial epidermis of grasses

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

The upper surface of the leaf is known as the adaxial surface. The type of cells presents in the adaxial epidermis of grasses is bulliform cells (only one type). These are large bubble-shaped cells present in the adaxial or upper surface of the leaves in monocots. So, the correct answer is '1'.

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot leaf internal structure of leaf (dicot and monocot) anatomy of leaf internal structure of dicot leaf

Bulliform cells differ from other cells in being

  1. Large, thin-walled, vacuolate containing water

  2. Large, thick-walled, contain abundant chloroplasts

  3. Small, thick-walled, contain starch

  4. Small, thin-walled, contain calcium oxalate
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The large sized, thin-walled, vacuolated, water containing colourless epidermal cells present on the adaxial epidermis of an isobilateral leaf or monocot leaf are called Bulliform cells. They differ from other cells in being size, structure and function.

So, the correct option is ‘large, thin-walled, vacuolated containing water’

Multiple choice botany internal structure of root, stem and leaf internal structure of monocot leaf internal structure of leaf (dicot and monocot) anatomy of leaf

Which one is correct about bulliform/ motor cell?

  1. It is seen in grasses.

  2. It is large-sized, colorless, vacuolate cells on the adaxial surface of monocot leaf.

  3. Both of the above

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

Bulliform cells or the motor cells are the modified epidermal cells present on the upper surface or the adaxial surface of the monocot leaf (the grasses). They are colourless, large-sized and vacuolated cells. They regulate the rolling of leaves to prevent the loss of water. When water is adequately present, they become turgid and keep the leaf open and exposed. When there is scarcity of water, the become flaccid and roll-up the leaf to prevent the loss of water.

Hence, the correct nswer is 'Both of the above'

Multiple choice zoology earthworm earthworm - reproductive system reproduction in earthworm introduction to reproduction

Nutritive substance for cocoon secreted by

  1. Mucous cells

  2. Albuminous cells

  3. Yellow cells

  4. All of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The clitellum plays an important role in reproduction. Its glands produce mucous which becomes a sheath containing nutritive material. The sheath slides forwards, collecting eggs and sperm from the genital openings of the worm. The sheath finally slides off from the head of the worm. As it separates from the worm, its ends are sealed. It now becomes a cocoon.

So, the correct option is 'Mucous cells'.

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

Which of the following involves in sectioning of tissues?

  1. Immunofluoresence

  2. Stain

  3. Microscope

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

The study of tissue is known as histology or, in connection with disease, histopathology. The tissues are studied by the use of paraffin block in which tissue is embedded and then sectioned, the histological stain and then observed under the microscope. Therefore, the correct answer is option D.

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

Tissue means _________________.

  1. Similar cells having common origin

  2. Similar cells having common origin and functions

  3. Cells having same metabolic activities

  4. Similar cells with same metabolic activity
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A tissue is defined as a group of similar cells that have a common origin and perform similar functions. This is the standard biological definition emphasizing both structural similarity (same origin) and functional unity (common function).

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

A tissue is a grouping of cells similar in

  1. Function

  2. Structure

  3. Heredity

  4. Origin and function
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
 A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues. The English word is derived from the French tissu, meaning something that is woven, from the verb tisser, "to weave". 
So, the correct answer is 'Origin and function.'
Multiple choice botany plant tissues introduction to tissue tissues - "the teams of workers" introduction to tissues

The tissue is defined as a group of

  1. Cells which are dissimilar in origin, but are similar in form and function

  2. Cells which are similar in origin, but dissimilar in form and function

  3. Cells which are dissimilar in origin, form and function

  4. Cells which are similar in origin, form and function
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In biology, tissue is a cellular organizational level between cells and a complete organ. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues. So, the correct option is "D" (Cells which are similar in origin, form, and function).