Tag: biology

Questions Related to biology

How many of the following statements are wrong:
(i) Increase in mass and increase in number of individuals are twin characteristics of reproduction.
(ii) In unicellular organisms, reproduction is synonymous with growth.
(iii) Cellular organisation of the body is the defining feature of life forms.
(iv) Photoperiod affects reproduction in seasonal breeders only in plants.
(v) Living organisms are self regulating interactive systems.

biology breath and blood of life different types of circulatory systems stomata and transpiration transport in organisms

  1. 1

  2. 2

  3. 3

  4. 4

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Correct Option: B

Enterohepatic circulation is related to

biology breath and blood of life different types of circulatory systems stomata and transpiration transport in organisms

  1. Bile ducts

  2. Bile pigments

  3. Cholesterol

  4. Cholecystokinin.

Show answer
Correct Option: B

Match column I with column II and select the correct option from the codes given.


Column I Column II
A. Hypotonic (i) No net flow of water
B. Hypertonic (ii) Water moves into the cell
C. Isotonic (iii) Water moves out of the cell

biology movement in and out of the cell diffusion across cells diffusion and osmosis inter cellular movement

  1. A-(ii), B-(iii), C-(i)

  2. A-(iii), B-(ii), C-(i)

  3. A-(i), B-(ii), C-(iii)

  4. A-(ii), B-(i), C-(iii)

Show answer
Correct Option: A

Many freshwater organisms cannot live for long in seawater because the surrounding water will be ______ to body cells and ______ may occur.

biology movement in and out of the cell diffusion across cells diffusion and osmosis inter cellular movement

  1. Hyper tonic, Exosmosis

  2. Hyper tonic, Endosmosis

  3. Hypo tonic, Exosmosis

  4. Hypo tonic, Endosmosis

Show answer
Correct Option: A
Explanation:

In the sea water , the surrounding water is salty and hence hypertonic to the body cells, Thus, water will move from its higher concentration to ts lower concentration leading to exosmosis. Therefore, many fresh-water animals cannot live for long in sea water and vice versa. 

Which of the following occupies the space between the cell wall and the shrunken protoplast in a plasmolysed cell?

biology movement in and out of the cell diffusion across cells diffusion and osmosis inter cellular movement

  1. Isotonic solution

  2. Hypotonic solution

  3. Hypertonic solution

  4. Water

Show answer
Correct Option: C
Explanation:

If a plant cell is kept in hypertonic solution, water comes out from the cell sap due to exosmosis. Water loss from the cell sap results in contraction of protoplast, which is referred to as plasmolysis. The cell is surrounded by the hypertonic solution, and the cell wall allows entry of most of the solutions. The hypertonic solution enters the cell wall freely but is not allowed to cross the cell membrane. 

Thus, the space between the cell wall and condensed protoplast is filled with hypertonic solution in a plasmolyzed cell.

A cell shrinks on being kept in a solution. The solution is 

biology movement in and out of the cell diffusion across cells diffusion and osmosis inter cellular movement

  1. Isotonic

  2. Hypotonic

  3. Hypertonic

  4. None of the above

Show answer
Correct Option: C
Explanation:
If a cell gets reduced in size or shrinks when placed in solution, the solution is hypertonic because a hypertonic solution has lesser concentration of solvent molecules than the fluid inside the cell so the solvent molecules are forced outside the cell from the region of higher concentration to the lower concentration by the process of exosmosis. The cell turns flaccid.
So, the correct answer is option C.

If the external solution balances the osmotic pressure of cytoplasm, it is said to be isotonic.

biology movement in and out of the cell diffusion across cells diffusion and osmosis inter cellular movement

  1. True

  2. False

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Correct Option: A
Explanation:

If the osmotic pressure outside the cytoplasm is the same as inside then it is known as an isotonic solution.

In an isotonic condition, amount of water entering the cell is the same as the amount of water going out of the cell. Hence no swelling or shrinking occurs.
So the correct answer is 'True'.

If alcohol treated cell is kept in hypertonic solution it___________.

biology movement in and out of the cell diffusion across cells diffusion and osmosis inter cellular movement

  1. Burst

  2. Remains same

  3. Plasmolysis

  4. None of these

Show answer
Correct Option: B
Explanation:
If alcohol-treated cell is kept in hypertonic solution, alcohol never enters into the cell, and the cell remains the same as alcohol prevents water loss from the cells.
So, the correct  option is 'remains same'.

The space between plasma membrane & cell wall of plasmolysed cell is occupied by?

biology movement in and out of the cell diffusion across cells diffusion and osmosis inter cellular movement

  1. Isotonic solution

  2. Hypertonic solution

  3. Hypotonic solution

  4. Water

Show answer
Correct Option: A
Explanation:

When a plant cell is placed in a hypertonic solution it will lose water by exosmosis. This process is called plasmolysis. The protoplasm will shrink and will move inwards and away from the cell wall. As a result, the hypertonic solution will occupy the space between the plasma membrane and the cell wall.

So, The correct answer is (B).

What will happen if we put a plant and animal cell in the isotonic solution?

biology movement in and out of the cell diffusion across cells diffusion and osmosis inter cellular movement

  1. No change

  2. Cell swells

  3. Cell shrinks

  4. Cell bursts

Show answer
Correct Option: A
Explanation:

An isotonic solution is a solution, which contains the same concentration of solute as in a cell. If animal and plant cells are kept in isotonic solution then cells will not swell or shrink. Hence, there will not be any change in cells.