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प्रश्न
Explain why:
Bacteria and fungi do not grow in pickles, jams, jellies and squashes.
उत्तर
Jam, jellies and pickles are kept in hypertonic solution of sugar or salt in which plasmolysis of bacteria and fungi takes place. This kills the bacteria and fungi and hence, pickles, jam and jellies are preserved properly.
APPEARS IN
संबंधित प्रश्न
(a) Mention whether the following statement is true (True) or false (False)
(b) Correct the false statement by altering the last word only.
A plant cell placed in hypotonic solution gets Plasmolysed.
Choose the correct answer:
Grapes when placed in a strong sugar solution shrink because of __________
Two potato cubes each 1 cm3 in size, were placed separately in two containers (A and B), the container A having water and the other (B) containing concentrated sugar solution. After 24 hours when the cubes were examined, those placed in water were found to be firm and had increased slightly in size and those placed in concentrated sugar solution were found to be soft and somewhat decreased in size. Use the above information to answer the questions that follow:
Name and define the physical process being investigated in this experiment.
Give Reasons for the following.
On sprinkling common salt on grass growing in a lawn, the grass is killed.
Give Reasons for the following.
Plants begin to die when the excess of soluble fertilizers are added to the soil?
A plant cell kept in a drop of water was examined under the low power magnification of a microscope, as shown:
(i) What would you do to bring this cell back to its original condition?
(ii) What scientific term is used for such condition?
(iii) Draw the same cell if it is kept in a strong sugar solution.
Fill in the Blank
The pressure which develops in the cortical cells of root which force a part of the water upward ____________.
Multiple Choice Question:
Marine fish when thrown under tap water bursts because of:
Multiple Choice Question:
When a plant wilts, the sequence of events will be as follows:
