sponge spawning. coral spawning - sperm coral spawning - eggs

Download Sponge spawning. Coral spawning - sperm Coral spawning - eggs

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  • Sponge spawning

  • Sponge spawning

  • Coral spawning - sperm

  • Coral spawning - eggs

  • Coral spawning - eggs

  • Palolo worm (polychaete annelid)Consist of anterior atoke and a posterior epitokeOn two or three nights, epitokes break free from the atokes and swim to the surfaceMass spawning of palolo worms

  • Palolo worms swarming

  • Palolo worms

  • Palolo worms

  • Uterine horns in some mammals

  • Acanthocephalans (spiny-headed worms

  • Acanthocephalan in situ

  • Acanthocephalan reproductionMales have an eversible penisAfter mating with a female, the males neatly cap the female gonopore with cementMales will also attempt to cement shut the gonopores of other males!

  • Last male advantageIn a number of animals with internal fertilization, the last sperm to enter the female reproductive system have the advantageExamples are birds and insects

  • Damselflies mating

  • Dragonflies mating

  • Dragonflies and damselfliesMale curls his abdomen to transfer sperm from the ninth abdominal segment to accessory genitalia on the second abdominal segmentThe male and female adopt the wheel position to transfer sperm to the femaleBefore copulating, the male will scoop out any pre-existing sperm from the females reproductive tractMales sometime hold on to the female while she ovipositsOther males hover around the female during oviposition

  • Onychophora

  • Onychophora reproductionMale deposits a spermatophore (a protective structure enclosing sperm) on the forest floorA female stumbles across a stomatophore and appresses her ventral side to the spermatophoreThe spermatophore causes her ventral body wall to rupture (ouch!), providing a means for sperm to enter her body

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