Tag: atp

Questions Related to atp

Choose the correct answer from the alternatives given.
If a cell is placed in an isotonic solution, what will occur?

  1. Salts will move into the cell from the surrounding solution

  2. Water will move into the cell from the surrounding solution

  3. Salts will move out of the cell into the surrounding solution

  4. None of the above will occur

Correct Option: D
Two or more isotonic solutions are those that have the same osmotic pressure across a semipermeable membrane. When a cell is placed in an isotonic solution, there will be no or equal exchange of salts between them; hence, then cells will neither shrink nor burst and there will be no movement of salts between the cells and the surrounding solution.

So, the correct answer is 'None of the above will occur'.

During phloem transportation sugar is moved in form of sucrose in to the companion cells and them into the living phloem sieve tube cells by -

  1. Passive transport

  2. Active transport

  3. Facilitated diffusion

  4. Osmosis

Correct Option: A

Pholem is the food-conducting tissue.

The sugar sucrose is transported from the companion cells to the sieve tube by the mechanism for simple diffusion because of the concentration gradient.
The concentration of the sucrose is higher in the companion cells an lower in sieve tubes.
So, the correct option is 'Passive transport'

A root concentrates minerals by?

  1. Active transport

  2. Facilitated diffusion

  3. Osmosis

  4. Diffusion

Correct Option: A

Percentage of water left in the soil when a plant begins to wilt is known as

  1. Wilting coefficient

  2. pH value of soil

  3. Field capacity

  4. Water holding cpacity

Correct Option: A

Water held tightly by soil particles around them is called as hygroscopic water. It is held in a very thin film and is not available to plants. Plants are able to absorb capillary water, which is present in the capillary spaces between soil particles. Run away water is also not available to plants. 

Field capacity denotes total water content in a field including hygroscopic water, capillary water and chemically bound water. 
The percentage of water left in soil when plants begin to wilt is called as wilting coefficient. At wilting coefficient soil contains hygroscopic and chemically bound water.

Absorption of mineral elements from the soil occurs through

  1. Diffusion

  2. Active transport

  3. Osmosis

  4. All of the above

Correct Option: B

Absorption of mineral elements from the soil involves active transport by the cells. Minerals may also be absorbed as ions rather than salts.

In trees, death of protoplasts is essential for vital function such as

  1. Stomatal movements

  2. Food transport

  3. Water transport

  4. Both water and food transport

Correct Option: C

Water transport is a physical process and not a physiological process. It does not require living cells and protoplasm. The driving force is the transpiration pull generated by loss of water through leaves. This is the reason why xylem tracheids and vessels are dead on maturity. Food transport is a physiological process and requires living cells similarly stomatal movement also is a physiological process and requires living cells.

Nobel prize in 1991 for discovering the single ion channels in cell was awarded to

  1. Waston and Har gobind Khorana

  2. Erwin Neher and Bert Sakmann

  3. Nirenberg and Kornberg

  4. Holley and Matthaei

Correct Option: B

In 1991, the Nobel prize in medicine or physiology was given to Erwin Neher and Bert Sarkmann for the discovery of single ion channels in cells. They were able to develop a technique that registers very minute variations in electric currents that passes through a single ion channel. This new method helped them to watch the activity of a single molecule.  

Thus, the correct answer is option B.

The process by which minerals get absorbed is

  1. Active absorption

  2. Passive absorption

  3. Both A and B

  4. None of the above

Correct Option: C

The minerals are mainly absorbed by roots which are in direct contact with the soil. Absorption of water is known as water uptake. Short distance transport of water takes place from cell to cell  across the membranes involving physical processes such as diffusion, osmosis and water potential differences. Long distance transport involves complex processes such as root pressure and transpiration pull. transport There are two processes by which mineral absorption takes place:

1. There is rapid uptake of ions into the outer free surface passively down the gradient of electrochemical potential energy. 
2.  The movement of ions into the inner space requires the expenditure of energy and is called active uptake.
Thus, the correct answer is option C. 

Which statement is incorrect for ion-channels?

  1. They are protein

  2. Movement through them is simple diffusion

  3. Movement through them is from high to low concentration

  4. All ions pass through the same type of channel

Correct Option: D

Ion channels are special proteins through which ions flow along the concentration gradient. These channels are important, because the membrane is made up of bilayer of lipids and will not allow transport of water soluble ions. However lipid soluble components can dissolve in membrane lipids and can be transported across the membrane without special carrier or transport proteins.
But all ions cannot pass through same transport protein because volume of each ion will be different. There are different transport proteins for transport of different ions.

ATP is required for

  1. Active process

  2. Passive process

  3. All types of processes

  4. None of the above.

Correct Option: A