Polytrichum:
Polytrichum is dioecious – Antheridia and archegonia is present
on different plants.
Gametophyte:
- The main plant body is gametophyte.
- Gametophyte is haploid. It develops antheridia and
archegonia.
- Antheridia produce antherozoids and archegonia produces
egg.
- Antherozoids fuse with egg to produce oosphore.
Sporophyte:
- Oosphore is the first stage of sporophyte generation.
- It is diploid.
- Sporophyte has 3 parts they are foot, seta and capsule.
- Haploid Spores are produced in the capsule by meiosis.
- Spore is the first stage of gametophyte.
- Spores germinate to a gametophyte protonema stage.
Marchantia:
The plant body is a gametophyte protonema, which develops from
the haploid spore.
Gametophyte:
- They are dioecious. Male reproductive plants are antheridia and
female is archegonia.
- Antheridia produces numerous male gametes but archegonia
produces only one egg.
- By means of rain water the sperm reaches the archegonia and
fertilize the egg.
- Zygote develops inside the archegonia into a sporophyte.
Sporophyte:
- The diploid sporophyte grows on the gametophyte.
- Inside the sporangium the meiotic division occurs, producing
haploid spores.
- The cap of the sporangium opens and spreads the spores.
- The spores then can grow into a new gametophyte.
Ceratopteris:
It has haploid heart shaped gametophyte generation and a diploid
sporophyte generation.
Gametophyte:
- The haploid gametophyte is either male or hermaphrodite.
- Antheridiogen determines whether it is male or
hermaphrodite.
- In the absence of antheridiogen, spores become hermaphrodite,
developing both antheridia and archegonia.
- In the presence of antheridiogen the spores develop only
male.
- Ceratopteris use water for fertilization; sperm swim to
fertilize the egg.
Sporophyte:
- After the fertilization, the sporophytes grow small roots and
leaves. The gametophyte dies.
- The sporophyte mature and undergo meiosis and produces
spores.
- These spores regenerates the life cycle.
Pine:
It has the dominant sporophyte generation.
Both the gametophyte and the next generation new sporophyte
develop on the parent body.
Sporophyte:
- Cones are formed on the mature sporophyte plant.
- Inside male cones, male spores develops into male
gametophyte.
- Inside female cones, female spores develop into female
gametophyte.
- Each female gametophyte develops a egg.
- Pollination occurs when pollen is transferred from male to
female cone.
- After fertilization diploid zygote is formed.
- The zygote develops into a embryo within the seed which is
formed from the ovule in the female cone.
- The seed germinates to a mature sporophyte tree.
Lily:
Lilly is a aromatic, flowering aquatic plants.
The root and stem of the lily plant grow under the surface of
water.
- Lilly begins its life cycle with a seed.
- The seed settles to the ground, becomes a seedling and
grows.
- Flowers are the sexual organs of the plant, upon maturity
flowers grow for reproduction with male and female parts, on the
mature sporophyte plant.
- Insects are the pollinator which goes inside the flower of lily
there by the pollen can reach the ovary and fertilize the egg.
- Fertilization results in the formation of seed.
- Seeds are released by plant and life cycle continues.