Angiosperms are a major group of land plants that include flowering plants. They have several key features including bearing seeds in an ovary of a carpel and producing flowers. Angiosperms are also the dominant plants in most terrestrial ecosystems and are the primary producers, providing the basis for most terrestrial food webs. They also have immense economic importance as they provide the vast majority of our food sources from grains, vegetables, fruits, and nuts. Additionally, many angiosperms are sources of important drugs and medicines used to treat diseases.

1. Economic importance of
Angiospermic Plants
Presented by- Pankaj Kushwaha
Department of Biomedical Sciences
BU Jhansi-284121

2. Angiosperms
• The angiosperms (also called flowering plants) are a major group
of land plants with 250,000 species.
• Angiosperms being seed plants, exhibit a life cycle that is in many
respects similar to that found in gymnosperms.
• Angiosperms comprise one of the two groups in the seed plants,
the other group being gymnosperms.
• The flowering plants cover their seeds by including them in a
true fruit.
• They bear the reproductive organs in a structure called a flower;
the ovule is enclosed within a carpel (female reproductive organ
of a flower), which will lead to a fruit. In gymnosperms, the ovule
is not enclosed at pollination and the seeds are not in a true fruit,
although occasionally fleshy structures may cover the seed.

4. General features
• Dominant sphrophytic plant
• Vessels present in their xylem and companion cells in the
phloem
• The ovule develops within ovary of a carpel and enclosed by
ovary wall
• All are heterosporous (producing mega and microspores)
• Pollination in angiosperms is indirect in which pollen is
deposited on the stigma of the carpel rather than directly on the
ovule as is the situation in gymnosperms.
• Double fertilization characteristically occurs in angiosperm to
produce embryo as well as endosperm, nutritive tissue for the
future embryo, is not haploid (n) but triploid (3n) and forms
after fertilization

5. Classification
• The flowering plants are usually treated as a division
in biology.
• The Cronquist system (Cronquist 1981), which places
flowering plants into two broad categories of
monocotyledons and dicotyledons, is still widely used but
is no lon
• the flowering plants are divided into two groups, which in
the Cronquist system are called Magnoliopsida (at the rank
of class, based on Magnolia) and Liliopsida (at the rank of
class, based on Lilium). ger believed to reflect phylogeny.

6. Flowering plant diversity
• Over 250,000 species of flowering plants have been described, within about
460 families.
• The most diverse families of flowering plants, in order of number of species,
are:
1. Orchidaceae (Orchid family): 25,000 or more species
2. Asteraceae or Compositae (Daisy family): 20,000 species
3. Fabaceae or Leguminosae (Pea family): 17,000
4. Poaceae or Gramineae (Grass family): 9,000
5. Rubiaceae (Madder family): 7,000
6. Euphorbiaceae (Spurge family): 5,000
7. Malvaceae (Mallow family): 4,300
8. Cyperaceae (Sedge family): 4,000
9. Araceae (including aroids subfamily): 3700
• In the list above (showing only the 9 largest families), the Orchidaceae,
Poaceae, Cyperaceae, and Araceae are monocot families; the others are dicot
families.

7. Economic importance
Primary producers
Source of Food
Source of Drugs

8. Primary Source
In most terrestrial ecosystems, angiosperms account for most of
the photosynthetic conversion of radiant energy into chemical
energy. Angiosperms thus for most terrestrial food chains

9. Source of Food
The vast majority of our food comes directly or indirectly from
angiosperms ;all cereal grains and most vegetables, fruits, and n
uts are obtained from angiosperms,-
most spices are obtained from angiosperms, and- most non-
alcoholic and alcoholic beverages are made from angiosperms.

10. Source of Drugs
Many angiosperms produce chemicals with significant medicinal properties.
Other angiosperms produce chemicals with significant effects on the human
central nervous system. Mescaline – from peyote cacti (Lopinophara),
Opium – from pappies (Papover), Cocaine – from coca plants (Erythroxylum),
Caffeine – from coffee plants (Coffea)
Quinine used in treating malaria
Vincristine used in treating leukemia
Curare used as a muscle relaxant in open-
heart surgery
Diosgenin used as a precursor to the active ingredient
in oral contraceptives