Snail Reproduction!
Snail reproductive system
Snails reproduce by sexual reproduction. Snails reproduce Most snails are hermaphrodites, which means that they possess both the male and female reproductive organs. The male reproductive organ is the penis sheath and the female reproductive organ is the ovaria. Snails reach sexual maturity at about age 1. Snails go through a particular mating custom that can last up to 12 hours. The snails preform a "love dance" where they circle around each other for several hours and touch tentacles/bite each other. The snails then press against each other and touch genital pores which stimulates the shooting of a "love dart" or spear like structure (known as the gyspobelum) into one another which is not necessary for the reproductions but signals for the snails to exchange sperm by internal fertilization. Fertilization occurs when the female and male gamete join. The female gamete is most commonly larger than the male gamete. These gametes are produced by meiosis.The love dart process is part of courtship. After sperm is exchanged eggs are fertilized in the ovaria. The haploid amount of chromosomes are 14. The genes of the snails are located on their chromosomes. Mitosis occurs in the development of the snail embyro.
Sources:
http://www.ndsu.edu/pubweb/~mcclean/plsc431/maternal/maternal1.htm
http://www.snail-world.com/How-do-Snails-Reproduce.html
http://en.wikipedia.org/wiki/Reproductive_system_of_gastropods
http://animals.about.com/od/mollusks/ig/World-of-Snails/Hibernation.htm
Sources:
http://www.ndsu.edu/pubweb/~mcclean/plsc431/maternal/maternal1.htm
http://www.snail-world.com/How-do-Snails-Reproduce.html
http://en.wikipedia.org/wiki/Reproductive_system_of_gastropods
http://animals.about.com/od/mollusks/ig/World-of-Snails/Hibernation.htm
Channeled Whelk Development!
Whelks develop in small egg cases laid by the mother for 3-13 months. Usually 100-150 eggs that are strung together are laid at a time. These egg capsules provide lots of protection and a good environment for the whelk embryos to develop. The eggs that hatch first often eat their siblings that are unborn. Whelks do not have a larvae stage unlike most gastropods. Instead as soon as they hatch as juveniles they are simply miniature versions of their adult selves. They are expected to live about 10 years and reach sexual maturity at about 5 years. After laying egg cases, the mother does not give her offspring any parental care whatsoever.
Sources:
http://www.asnailsodyssey.com/LEARNABOUT/WHELK/whelRepr.php
http://molluscs.at/gastropoda/index.html?/gastropoda/sea/common_whelk.html
http://www.sussex-ifca.gov.uk/index.php?option=com_content&view=article&id=77&Itemid=173
Sources:
http://www.asnailsodyssey.com/LEARNABOUT/WHELK/whelRepr.php
http://molluscs.at/gastropoda/index.html?/gastropoda/sea/common_whelk.html
http://www.sussex-ifca.gov.uk/index.php?option=com_content&view=article&id=77&Itemid=173