Tag: botany

Questions Related to botany

Which one is the driving force for the process of passive absorption of water in roots?

  1. Root pressure

  2. Transpiration in leaves

  3. Activity of aquaporins

  4. Increase in imbibition pressure in root cells


Correct Option: B
Explanation:

Passive absorption is absorption by the pull from transpiration without the active involvement of root cells, The shoots and leaves of the plant experience transpiration due to evaporation of water from their surface.

So, the answer is, "Transpiration in leaves".

Transpiration ratio is the ratio of moles of H$ _{2}$O transpired / moles of CO$ _{2}$ fixed. This ratio is measure of

  1. The efficiency of guard cells on stomatal movement.

  2. Effectiveness of stomata is maximizing photosynthesis, while minimizing water loss.

  3. Distinguishing a xerophyte from a glycophyte.

  4. Stomatal pore size of the leaves.


Correct Option: B
Explanation:

Water is required to generate the reducing power, which is used to reduce carbon dioxide during photosynthesis. The water molecules are split up and oxygen released as a by-product. The protons are used to synthesize reducing power. Now all the water that is absorbed is never used up. In fact, the water that is actually used is a small fraction of water that is absorbed. Hence, transpiration ratio is calculated to find out the effectiveness of stomata in maximizing photosynthesis and minimizing loss of water.

Water moves up against gravity and even for a tree of $20$m height, the tip receives water within two hours. The most important physiological phenomenon which is responsible for the upward movement of water is ____________.

  1. Cohesive forces

  2. Adhesive forces

  3. Transpiration pull

  4. Root pressure


Correct Option: C
Explanation:

According to transpiration pull theory, due to transpiration, the water column inside the plant comes under tension. This is called 'transpiration pull'. On account of this tension, the water column is pulled up passively from below to top of the plant(almost like a rope). A tension of one atmosphere is sufficient to pull water to a height of about $20$ meters.

So, the correct answer is 'Transpiration pull'

Choose the correct answers from the alternatives given.
Which of the following forces is responsible for moving water up to the tops of the tallest trees?

  1. Atmospheric pressure

  2. Root pressure

  3. Guttation

  4. Transpiration


Correct Option: D
Explanation:

Loss of water from the leaves causes water stress to develop from the top of the trees which forces more and more water to rise from the roots to the leaves. The column of the water is maintained due to cohesion and adhesion forces and the water moves up due to transpiration pull.

Hence,the correct answer is 'Transpiration'.

Choose the correct answers from the alternatives given.
What is the action spectrum of transpiration?

  1. Blue and infra red

  2. Green and ultraviolet

  3. Orange and red

  4. Blue and red


Correct Option: D
Explanation:

An action spectrum is a graph of the rate of a physiological activity plotted against the wavelengths of light. it shows which wavelengths of light is most effectively used in a specific reaction. In photosynthesis, chlorophyll is much more efficient at the blue and red wavelengths of light to carry out photosynthesis. Since transpiration is indirectly related to photosynthesis, its action spectrum would be similar to photosynthesis.

Hence, the correct answer is 'Blue and red'.

Choose the incorrect statement regarding herbarium.

  1. Dried specimens are poisoned by using DDT

  2. The collections are kept inside metallic vasculum

  3. Herbarium sheet is $41\times 29$cm

  4. It is used for alpha taxonomic research


Correct Option: A

Which of the following chemicals is used for poisoning the specimens in herbarium technique?

  1. $Hg _2Cl _2$

  2. $AgNO _3$

  3. $HCl$

  4. $HgCl _2$


Correct Option: A

How many collection of specimen in central national herbarium (Sibpur)?

  1. $888000$

  2. $2500000$

  3. $8880000$

  4. $250000$


Correct Option: A

Duplicate of holotype from same collection of same locality, date and same branch of plant is called

  1. Syntype

  2. Paratype

  3. Neotype

  4. Isotype


Correct Option: D
Explanation:
Isotype (in plant taxonomy) A plant specimen that is a duplicate of or very similar to the type specimen and can be used as a reference specimen if the type specimen is lost. In simple language, the isotype is the duplicate of the holotype.
So the correct option is 'Isotype'.

Find out the correct sequence of various stages in a herbarium preparation:
$(i)$ Drying. $(ii)$ Poisoning. $(iii)$ Collection. $(iv)$ Labelling. $(v)$ Mounting. $(vi)$ Deposition. $(vii)$ Stitching.

  1. $(iii)\, \rightarrow \, (i)\, \rightarrow \, (ii)\, \rightarrow \, (v)\, \rightarrow
    \, (vii)\, \rightarrow \, (iv)\, \rightarrow \, (vi)$

  2. $(iii)\, \rightarrow \, (ii)\, \rightarrow \, (i)\, \rightarrow \, (v)\, \rightarrow
    \, (vii)\, \rightarrow \, (iv)\, \rightarrow \, (vi)$

  3. $(iii)\, \rightarrow \, (i)\, \rightarrow \, (ii)\, \rightarrow \, (v)\, \rightarrow
    \, (vii)\, \rightarrow \, (vi)\, \rightarrow \, (iv)$

  4. $(iii)\, \rightarrow \, (i)\, \rightarrow \, (ii)\, \rightarrow \, (vii)\, \rightarrow
    \, (v)\, \rightarrow \, (vi)\, \rightarrow \, (v)$


Correct Option: C