#Sexual Reproduction:
Both meiosis & fertilization are essentially present.
Uniparental and biparental.
⬇️ ⬇️
1) hermaphrodite. 1)most animals
animals. 2)dioecious plants
2)monoecious plants. ⬇️.
↙️ ↘️ Separate ♂️& ♀️plants
Bisexual. Unisexual Ex: date palm,papaya
Flower flower
Ex. Mustard,. ⬇️
Pea,. But male and female
China rose. Flower on same plant
Ex: maize, cucurbits
Sexual Reproduction is more complex, elaborate and time taking
Phases:
Juvenile phase :- Time period before reproductive maturation of organism.
In plants, it is time period before first fflowering.
Reproductive phase : - Time period where organism is reproductively fertile.
Senescent Phase - Involve aging & death.
→ In annual & biennial plants-
⬇️. ⬇️
(4-5 monthy) (15-16 months)
Juvenil - Vegetative
Reproductive - Flowering & Fruiting.➡️ Once in life
Senescence. of monocarpic plant
Perennial plants Grow for multiple years
1) Some are monocarpic Ex: Bamboo (50-100 yrs)
↳ Flowering, fruiting only once.
11) Perennial & Polycarpic Flowering➡️fruiting multiple times.
Ex: mango
Time period between two flowering seasons = Intermediate gap of reproductive phase.
Strobilanthus Kunthiana (Neelakuranji) :- Flowers of this plant are observed at a gap of 12 yrs.
This is an Annual Plant & complete its life cycle in about 6 months, remaining gap of flowering is spent in seed dormancy.
Flowers observed after 12yrs are on new plant
This plant is found in Nilgiri hills, (Kerala & Karnataka)
Stages:
Pre- fertilization-
Gamete formation :- if parent plant haploid
⬇️ Mitosis
Gamete
Eg. Most algae, bryophyte and pterido prothallus
Meiosis
If parent organism diploid (2n) ➡️ Gametes
Ex: Most animals and Higher Plants
* Spirogyra ➡️Iso-aplanogamy
⬇️
Male gamete➡️ Amoeboid Movement.
* Red Algae - Oogamy but no flagella
⬇️
Male gamete ➡️Amoeboid Movement
Gamete transfer :- (Algae, Bryophyte, pteridophyte)➡️ water
Gymno, Angio - Pollen tube
In seed forming plants, seed setting or formation is more successful as it is not depended on water for fertilisation.
Fertilisation :-
External fertilisation:- In water ➡️ in most algae. Exception - Spirogyra, Chara -Internal
Internal fertilisation-: Bryo, Pterido, Gymno -➡️Inside archegonium
Angio ➡️Embryo Sac
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