Q. Fill in the blanks:
1. In plant cells the vacuoles can occupy up to (a)______ of the volume of the cell.
2. In plants, the tonoplast facilitates the transport of a number of ions and other materials (b)______ concentration gradient into the vacuole, hence their concentration is significantly (c)________ in the vacuole than in the cytoplasm.
3. In Amoeba the (d)________ vacuole is important for excretion.
4. In many cells, as in protists (e)______ vacuoles are formed by engulfing the food particles.

 2356  239 Cell : The Unit of Life Report Error

Solution:

a. In plant cells the vacuoles can occupy up to 90% of the volume of the cell
b. In plants, the tonoplast facilitates the transport of a number of ions and other materials against concentration gradient into the vacuole, hence their concentration is significantly higher in the vacuole than in the cytoplasm.
c. In Amoeba the contractile vacuole is important for excretion.
d. In many cells, as in protists food vacuoles are formed by engulfing the food particles.