BOTANY Higher Secondary Second Year - Textbooks Online

1. Beverage plants
ECONOMIC IMPORTANCE
The seeds of Coffea arabica (Coffee plant) are roasted and powdered
for making coffee. The stimulating effect of coffee is due to the presence
of alkaloid “caffeine”.
2. Medicinal plants
The drug ‘quinine’ obtained from the bark of Cinchona officinalis is
used throughout the world in the treatment of malarial fever. The extract
obtained from the fruits of Randia tinctoria possesses insecticidal and
insect repellant properties.
3. Dye plants
The dyes alizarin and purpurin are obtained from the roots of Rubia
tinctoria (madder). A red dye is extracted from the root and barks of
Oldenlandia umbellata (Dye root). A yellow dye is obtained from the
barks of Morinda angustifolia.
4. Timber plants
Timber of commercial value is obtained from Adina cordifolia
(Manjakkadambu) and Morinda tinctoria (Nuna tree).
5. Ornamental plants
Gardenia jasminoides (cape jasmine), Ixora coccinea (Iddlipoo) and
Mussaenda frondosa (Vellai madandhai) are grown in gardens.
Self evaluation
I . Choose and write the correct options.
1. Rubiaceae is placed under the series
a. Inferae b. Heteromerae
c. Bicarpellatae d. Unisexuales
2. The phyllotaxy in Ixora coccinea is
a. alternate b. opposite decussate
c. whorled d. spiral
3. In Ixora coccinea, the stamens are
a. monadelphous b. syngenesious
c. epipetalous d. diadelphous
33