Tag: cell-the basic unit of life

Questions Related to cell-the basic unit of life

A distinguishing feature of latex cells is that they are

  1. Single celled elements with anastomosing branches

  2. Single celled elements with nonanastomosing branches

  3. Multicelled elements with anastomosing branches

  4. Multicelled elements with nonanastomosing branches.


Correct Option: B

Which amongst the following is more complex in body plan, from evolution point of view?

  1. Bacteria

  2. Human

  3. Both have same complexity

  4. Data insufficient


Correct Option: B
Explanation:

If the appearance of complexity is concurrent with evolution then, human beings are more evolved and complex than bacteria. Humans are the multicellular organism with the well-developed brain. Bacteria is the primitive unicellular organism.

safranin stains

  1. Thick walled cells

  2. Lignified cells

  3. Suberized cells

  4. LIving cells


Correct Option: B
Explanation:

Safranin is a biological stain composed of azonium compounds, which is utilized to study histology and cytology. In particular, safranin stains lignified tissues like xylem even in the presence of cellulose particles. Fluorescent safranin staining is useful to stain the cell wall of woody plants and produce green or yellow fluorescence in the secondary cell wall and red or orange fluorescence in the middle lamella region under a fluorescent microscope. 

So, the correct answer is option B, Lignified cells. 

The longest living cells amongst the following are

  1. RBC

  2. B cells

  3. T cells

  4. Neurons


Correct Option: D
Explanation:

All cells usually have a fixed life span. The cells divide for a certain period of time, after which they die. This has been explained by the phrase "programmed cell death". The lifespan of each type of the body cells differ and it depends on the function it is destined to perform. Neurons are long lived and are generally non-mitotic. Memory T cells and memory B cells can provide long lasting immunity from exposure to antigens, they too are long lasting but their life span is less than that of a neuron.

The lifespan of RBC is shortest amongst the options which are given, it is 115 days. Thus, the correct answer is option D.

PPLO is the smallest cell.

  1. True

  2. False


Correct Option: A
Explanation:

PPLO is pleuropneumonia-like organisms. It has the diameter of 0.1 micrometer. It is the smallest known cell. 

The largest cell measuring .........., is the egg of an ostrich.

  1. 130 mm-150 mm

  2. 130 mm-180 mm

  3. 130 mm-170 mm

  4. 170 mm-190 mm


Correct Option: C
Explanation:

The cell is the structural unit of life and its size ranges from 0.5 micrometers to 100 micrometers. An egg of ostrich is a single-celled structure and know as the largest cell in the world with the size of 130 mm-170 mm. Thus, the correct answer is option C.

The nucleus is separated from cytoplasm by

  1. Protoplasm

  2. Cell membrane

  3. Cell wall

  4. Nuclear membrane


Correct Option: D
Explanation:

In the eukaryotic cell, the nucleus is separated from the cytoplasm by a double lipid bilayer membrane known as a nuclear membrane. It encloses the genetic material of a cell. It is also known as karyotheca.

Which of the following is a membrane enclosed organelle found in eukaryotic cells containing most of the cell's genetic material?

  1. Nucleus

  2. Cytoplasm

  3. Vacuoles

  4. Plasmalemma


Correct Option: A
Explanation:

A eukaryotic cell has a nucleus bounded by a double wall membrane structure known as a nuclear membrane. The nuclear membrane has nuclear pore that regulates the exchange of materials between cytoplasm and nucleoplasm. The nucleus contains the chromatin threads and the nucleolus. The gel-like texture of the nucleoplasm embedded with chromatin threads gives it a dense appearance.

What is the central role of nucleus?

  1. Diffusion

  2. Osmosis

  3. Excretion of toxic materials

  4. Reproduction


Correct Option: D
Explanation:

A eukaryotic cell has a nucleus, bounded by a double wall membrane structure known as a nuclear membrane. The nuclear membrane is a discontinuous membrane having nuclear pores, which act as a protein channel for regulating the exchange of materials between cytoplasm and nucleoplasm. It regulates the cell in various ways but, the primary function of the nucleus is to contribute in cell division during reproduction by undergoing karyokinesis.
So, the correct answer is option D.

Which part of the cell contains genetic information?

  1. Plasma membrane

  2. Nucleus

  3. Chloroplast

  4. Mitrochondria


Correct Option: B
Explanation:

The DNA is the genetic material of the organism which is present in the nucleus. The DNA is bound to the histone proteins and packaged in the nucleus. The DNA contains the segments of genes which encode for the proteins. This genetic information is present in the nucleus of the living cells. 

Thus, the correct answer is option B.