1. Angiosperm Reproduction
A Botany Application

2. Background

3. Through the span of geological time, major groups of vascular plants have risen to dominance, only to decline to small groups within the flora of the Earth
The Angiosperms or flowering plants are the group that is now in total dominance on our planet

4. We live in the "Age of the Angiosperms"
We live in the "Age of the Angiosperms". There are more than 250,000 species, grouped into 12,500 genera and about 300 families
Angiosperms dominate almost every terrestrial habitat – except the tundra and northern coniferous forest

5. Because of their abundance and distribution, Angiosperms are a major part of the environment of other organisms
They have a huge effect on other organisms, especially those that eat them
Herbivorous mammals have dramatically increased in numbers with the worldwide spread of grasses

6. The success of Angiosperms is directly related to their flowers – or reproductive structures
Many flowers have bright colors, attractive shapes, and pleasant aromas

7. These features help to ensure successful sexual reproduction as they attract organisms
Also, Angiosperms have a way of dispersing its seed which gives it the ability to move great distances

8. Parts of a Flower

9. Angiosperms are classified by the structure of their flowers
The parts and the arrangement of those parts is an important identification key

11. Receptacle - the top of the stem that supports the flower
Sepals - collectively they are called the calyx (CA)
They are the outermost floral parts and are usually leaf-like and green
They enclose the bud of the flower

12. Petals - collectively they are called the corolla (CO)’
They are just inside the sepals, petals are usually delicate and brightly colored in order to attract insects

13. Stamens - collectively they are called androecium (A)
Word origin andro means “male”
They are the male reproductive parts of the flower and are located inward from the sepals and petals

14. Stamens are comprised of:
Anther - the sac-like part which contains the pollen
Filament - the stalk that connects the anther to the flower

15. Anthers can be attached to the filament in a number of ways:

16. Pistils - collectively are called the gynoecium (G)
Word origin gyno means “female”
They are the female reproductive parts of a flower
They are located in the center of the flower

17. Pistils are generally are comprised of:
Stigma - the pollen-receptive part at the top. The surface of the stigma is sticky which allows it to trap pollen grains
Style - the stalk that connects the stigma to the ovary

18. Ovary - the enlarged section at the base where egg cells are produced
Carpels are the basic unit of the ovary
There is one seed and one stigma for each carpel

19. Arrangement of Flower parts

20. Flower parts are normally arranged in four concentric circles called whorls

21. The sepals protect the developing flower and make up the outermost whorl
The petals are usually brightly colored and make up the next inside whorl

22. The stamen is found in the next whorl and contains the anther and its filament
The innermost whorl contains carpels – the basic ovary unit

23. Some flowers may be missing some of basic flower parts
Complete flowers have all four flower parts: sepals, petals, stamens, and pistils
Incomplete flowers are missing 1 or more of the flower parts

24. A perfect flower will have a stamen and a pistil
An imperfect flower will be missing a stamen or pistil
perfect imperfect imperfect

25. Flower parts by multiples

26. A monocot will typically have its flower parts in multiples of 3
3 or 6 sepals
3 or 6 petals
3 or 6 stamens
3 or 6 pistils

27. A dicot will typically have flower parts in multiples of 4 or 5
4, 5, 8, 10 sepals
4, 5, 8, 10 petals
4, 5, 8, 10 stamens
4, 5, 8, 10 pistils

28. Floral Formulas - Diagrams

29. A floral formula is way to show the structure of a flower using symbols
 The standard set of symbols are shown below:

30. These floral parts will always be listed in the same order
First sepals CA
Second petals CO
Third stamens A
Fourth carpels G

31. The numbers of each flower part is shown using a superscript after its letter
CA – Co – A - G

32. The numbers of each flower part is shown using a superscript after its letter
CA – Co – A - G

33. A floral diagram is a way to show the cross-section of a flower
This would be how it would appear if all of its parts were at the same horizontal level
A floral diagram is a good representation of a flower

34. The 4 symbols representing basic floral parts:

35. When floral structures are fused (attached to each other) they are connected with a line on the diagram
Notice the symbol on the right
indicates fused petals 

36. Angiosperm Reproduction
The End