Page 99 - General and Inorganic Chemistry for Advanced Secondary Schools Students Book Form Five and Six

Biology for Secondary Schools

Classes of the division (b) They have parallel leaf venation,
Angiospermophyta as shown in Figure 5.22 (b).
The division Angiospermophyta is (c) The embryo of monocot seeds
bears one cotyledon.
divided into two classes. These classes are (d) Monocot leaves are composed of
FOR ONLINE READING ONLY
Monocotyledoneae and Dicotyledoneae. an open or closed sheath which
The word “Mono” means one and “Di” encloses the stem.
means two. Monocots have been named (e) Their vascular bundles in stems

from having one cotyledon and dicots are scattered, as shown in Figure
from having two cotyledons. Cotyledon 5.23 (a).
is the part of seed that develops into the (f) They have fibrous root system
leaves after germination. (Figure 5.23 (b)).
(g) They have long and thin leaves.
Class Monocotyledoneae
This class contains plants with one
cotyledon. Examples of plants in this
class include maize, sugarcane, wheat,
millet, sisal, coconuts and banana
plants.

Distinctive features of the class
Monocotyledoneae
(a) Flower parts normally occur in
three or multiples of three. See Figure 5.22: Monocot plant (a) floral
Figure 5.22 (a). arrangement (b) parallel leaf venation

Figure 5.23: Monocot stem and root (a) vascular bundle scattered in stem (b) fibrous
root system

Student’s Book Form One Student’s Book Form One 93

15/10/2024 09:24:34
Biology FORM 1 new.indd 93
Biology FORM 1 new.indd 93 15/10/2024 09:24:34