Transcript Ch 22 Introduction to Plants

1.
2.
3.
Form a Hypothesis Which are more likely to be
dispersed by animals- the seeds of an angiosperm
or a gymnosperm- explain
Explain How do the three methods of
categorization differ from scientific methods
Form an Opinion Is it useful or misleading to
categorize angiosperms in ways that do not reflect
evolutionary relationships- defend your opinion
CH 22 INTRODUCTION TO PLANTS
22.4 Flowering Plants


Flowering plants are by far the most abundant
organisms in the plant kingdom
They evolved much more recently than did other
seed plants.
Flowers and Fruits


Angiosperms reproduce sexually by means of
flowers
After fertilization, ovaries within flowers develop
into fruits that:
 Surround
 Protect
 Help
disperse the seeds.

Ovaries
 Surround
and protect seeds inside of flower.
Advantages of Flowers


Attract animals that carry pollen with them to the
next flower they visit
More efficient pollination than gymnosperms.
Advantages of Fruits

Fruit
 Structure


containing one or more matured ovaries
Seeds from the fruit enter the animal’s digestive
system after it eats a fruit
Seeds travel a far distance before leaving the
digestive system.
Angiosperm Classification

Cotyledons
 Number

Monocot
 One

of seed leaves
seed leaf
Dicot
 Two
seed leaves.

Pg 543.
Angiosperm Diversity

Grouped according to:
 Number
of their seed leaves
 Strength and composition of their stems
 Number of growing seasons they live.
Monocot Vs Dicot

Differences include the distribution of vascular
tissue in stems, roots, and leaves, and the number
of petals per flower.

Woody plants
 Made
primarily of cells with thick cell walls that
support the plant body

Herbaceous plants
 Have
stems that are smooth and nonwoody.