Tag: plant physiology

Questions Related to plant physiology

Which of the following is related with transfer of food material?

botany plant physiology mineral absorption transport of food, water and minerals mineral transport theories of translocation transport in the phloem of plants

  1. Xylem

  2. Collenchyma

  3. Phloem

  4. Parenchyma

Show answer
Correct Option: C
Explanation:

Xylem tissue is comprised of dead cells involved in the process of transport of water and minerals. Transport of water is under the influence of transpiration pull and is a physical process. 

Phloem tissue is comprised of living cells involved in the process of translocation of sugars. Translocation of sugars requires living cells and is a physiological process. The sugars are transported under the influence of pressure difference between source and sink, which leads to mass flow.

Leaf photosynthates are transported to other parts of higher plants through

botany plant physiology mineral absorption transport of food, water and minerals mineral transport theories of translocation transport in the phloem of plants

  1. Cambium

  2. Pith

  3. Xylem

  4. Phloem

Show answer
Correct Option: D
Explanation:

Phloem is involved in transport of sugars. Phloem cells are living cells, which carry out the physiological process of sugar transport in higher plants.

By many evidences, it can be known that the downward movement of food takes place through

botany plant physiology mineral absorption transport of food, water and minerals mineral transport theories of translocation transport in the phloem of plants

  1. Phloem

  2. Xylem

  3. Collenchyma

  4. Sclerenchyma

Show answer
Correct Option: A
Explanation:

Movement of food takes place through phloem tissue. This can be demonstrated through ringing experiment in which, if ring of vascular tissue including phloem is removed in a dicot tree. The plant parts located below the point of ringing will die because these parts do not get food.

Thus, the correct answer is option A.

How many of the following features are related to Dixon and Jolly model of water transport in plants?
a. Cohesion between water molecules
b. Transpiration pull
c. Pushing of water by negative root pressure
d. Surface tension
e. Pushing of water by positive root pressure.

botany plant physiology mineral absorption transport of food, water and minerals mineral transport theories of translocation transport in the phloem of plants

  1. $4$

  2. $5$

  3. $2$

  4. $3$

Show answer
Correct Option: A

Bulk flow or mass flow.

botany plant physiology mineral absorption transport of food, water and minerals mineral transport theories of translocation transport in the phloem of plants

  1. Can be achieved through root pressure

  2. Can be achieved through transpiration pull

  3. Can be achieved either through a positive Hydrostatic pressure or a negative hydrostatic pressure

  4. More than one option is correct

Show answer
Correct Option: A

Select the odd one our w.r.t. porins.

bio-chemistry plant physiology active transport and passive transport types of plant transport atp

  1. Not associated with the inner membrane of plastids

  2. Associated with the outer membrane of mitochondria

  3. Found in outer membrane of gram positive bacteria

  4. Allow movement of low molecular weight hydrophilic substances

Show answer
Correct Option: A
Explanation:

Porins are beta barrel proteins that cross a cellular membrane and act as a pore, through which molecules can diffuse. Unlike other membrane transport proteins, porins are large enough to allow passive diffusion, i.e., they act as channels that are specific to different types of molecules. Porins from non-green plastids and from the outer mitochondrial membrane were re- constituted into planar lipid bi-layers. The proteins showed high pore-forming activities and similar single- channel conductance. So, the correct option is "Not associated with the inner membrane of plastids".

Facilitated diffusion can be differentiated from active transport except

bio-chemistry plant physiology active transport and passive transport types of plant transport atp

  1. Energy does not required

  2. Show saturation effect

  3. Accumulation of molecule

  4. (1) and (3) both

Show answer
Correct Option: D
Explanation:

In facilitated diffusion ,special proteins help move substances across membranes without expenditure of  ATP energy. While in case of Active transport it uses energy to pump molecules against a concentration gradient .

In both case , transportation rate reaches a maximum when all of the protein transporters are being used (saturation).
So the correct option is 'One and three both' .

The process of facilitated diffusion is different from active transport due to

bio-chemistry plant physiology active transport and passive transport types of plant transport atp

  1. Involvement of membrane protein

  2. Its response to protein inhibitors

  3. Being a downhill process

  4. Saturation of transport

Show answer
Correct Option: A

Facilitated diffusion can not cause net transport of molecules from a low to a high concentration because -

bio-chemistry plant physiology active transport and passive transport types of plant transport atp

  1. This would require output of energy

  2. This would require Input of energy

  3. Both (1) and (2)

  4. None of these

Show answer
Correct Option: A

The physical process involved in the release of molecular oxygen from leaves is

bio-chemistry plant physiology active transport and passive transport types of plant transport atp

  1. Diffusion

  2. Transpiration

  3. Osmosis

  4. Capillarity

Show answer
Correct Option: A
Explanation:

Diffusion is a slow process and is not dependent on a living system. Diffusion is very important to plants since it the only means for gaseous movement within the plant body. Intake of carbon dioxide and release of oxygen through stomata occurs through the process of diffusion. Diffusion rates are affected by the gradient of concentration, the permeability of the membrane separating them, temperature and pressure.