1. Reproduction with cones and
flowers
• Alternation of generations
• Diploid sporophyte generation alternates
with haploid gametophyte generation

2. Life Cycle of gymnosperms
• Takes place in cones, which are produced
by a mature sporophyte
• Pollen cones - male – pollen grains
• Seed cones – female – ovules - which
develop into a new embryo following
fertilization

3. Structures of Flowers
• Sepals – protection during development
• Petals – located inside sepals, used to
attract pollinators
• Stamens – male parts consisting an
anther and filament,
• filament – long stalk that supports the
anther
• Anther – oval sac where meiosis takes
place

4. Cont.
• Carpels – innermost floral part – (pistils)
where ovary produces gametophytes
• From the ovary, a stalk extends narrowing
into the style, at the top is the sticky
stigma

5. Life cycle of angiosperms
• Reproduction takes place within the
flower. Following pollination and
fertilization, the seed develop inside
protective structure
• Pollination for most angiosperms is by
animals

6. Fertilization
• Occurs when pollen lands on same
species, pollen tube grows into style
releasing two sperm nuclei
• 1 Sperm fuses with egg to produce diploid
zygote, 2nd fuses with nuclei in embryo-sac
which will grow into food-rich tissue called
endosperm

7. Seed development and germination
• Angiosperm seeds mature the ovary walls
thicken to form a fruit that encloses the
developing seed
• Seeds dispersed by animals are typically
contained in fleshy, nutritious fruits
• Wind and water require seeds that are
lightweight to be carried or float

8. Cont.
• Dormancy – seed is alive, just not growing
• Factors like temperature and water can
change dormancy
• Germination – seed absorbs water,
cracking open seed coat, roots emerge
and seed begins to grow

9. Plant Propagation
• Vegetative reproduction includes the
production of new plants from horizontal
stems, from plantlets, and from roots
• Plant propagation –cuttings, grafting or
budding is use to make many identical
copies of a plant or to produce offspring
from seedless plants

10. Agriculture
• 10,000 to 12,000 – people began to
harvest food
• Most people world wide depend on a few
crops; wheat, rice, corn