Saturday, July 4, 2020

EASY BOTANY TASTY BOTANY -a magic botanical touch 

REPRODUCTION IN ORGANISMS  part 3  prefertilisation
events of sexual reproduction prior to fuion of gametes, includes gametogenesis  and gamete transfer.
GAMETOGENESIS- process of formation of haploid male and female gametes.
HOMOGAMETES-gametes simillar in appearance.
HETEROGAMETES- gametes dissimilar in appearance .(male- antherozoid /sperm;female egg /ovum)
BISEXUAL,/ MONOECIUS /HOMOTHALLIC     /
HERMAPHRODITE (ANIMALS like earth worm ,leech ,tape worm , sponge )male and female reproductive strucures on  same organism.eg  cucurbits ,coconut .
UNISEXUAL/DIOECIUS  / HETROTHALLIC . male and female reproductive structures on Different organisms. eg papaya,  date palm , marchantia , cockroach .
unisexual male flower - staminate , unisexual female flower - pistillate 
CELL DIVISION DURING GAMETE FORMATION 
gametes are haploid   in haploid plants (algae , fungi, bryophytes)  gametes produced by MITOSSIS.
in diploid organisms specialised cells known as meiocytes or gamete mother are produced  which undergoes MEIOSIS and produces haploid gametes.

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