Exponential growth is shown by:
1.  Unicellular forms
2.  A cell in tissue culture
3.  Embryo
4.  Multicellular plants

Geocarpic fruit is:

1. Potato

2. Peanut

3. Onion

4. Garlic

Differentiation of shoot is controlled by:

1. High auxin : cytokinin ratio

2. High cytokinin : auxin ratio

3. High gibberellin : auxin ratio

4. High gibberellin : cytokinin ratio