The egg cells of the female snail are stored in the ovaria, which are located in the top of the spine, closely to the digestive system.
To produce an egg, the egg cell is brought to the receptaculum seminis. In this place, where the sperm from the male is stored, the fertilisation of the egg cells takes place.
The spermatozoa (sperm cells) of the male can survive for more than a month in the female, and several egg clutches can be fertilised with a single copulation.
The albumen (yolk) from which the snail embryo is living is added by the proximal albumen gland and further during its way through the eggs tube by the distal albumen gland.
These glands increase considerably when the female is about to produce eggs. And while the ovaria are located in the top of the shell, the albumen glands are located in the top of the mantle cavity and in the reproductional season they move closer to the shell opening and can even fill a large part of the right mantle cavity.
The male reproductive tract consist of the testis and vas deferens, the seminal vesicle and the prostate gland, the penial sac, the penis and the penis sheath.
The cream-yellow testis can be found in the upper part (1.5 to 2.5 coils) o
f the shell along the dark coloured digestive gland.
The short tubules (vasa efferentia) inside the testis fuse to form the vas deferens.
The vas deferens passes down to the seminal vesicle, beneath the kidney chamber. In this seminal vesicle, the sperm cells are stored.
The prostate gland is closely connected with the seminal vesicle and is situated next to the seminal vesicle (they appear as one structure from the outside).
The prostate gland passes down the right margin of the mantle skirt, along the rectum and ends in the penial papilla, next to the anal papilla at the roof of the right mantle cavity.
During mating activities, this penial papilla bends towards the sperm groove in which the sperm is conducted. From this sperm groove the sperm is conveyed in the penial duct at the base of the penis.
The penis itself is coiled in a basal pouch (penial sac) when not used. On erection the penis comes out of the penial sac and is grasped around on the lower thirth by a muscular penial sheath from the mantle. It's the latter, which can be seen when the snails are mating. The real penis is rather thin, whip-like and often stays out of sight.
WATER SNAIL
Members of the Ampullariidae family are either male or female. Males and females of some species can be distinguished by shell-shape, but for many, there is no outward physical difference. Upon examination of the mantle, however, the male will have a relatively large penis sheath in front of the gills, the female will not.
A female Pomacea snail will lay her eggs in clutches above the waterline, generally at night. Usually 200 to 600 eggs can be laid. Eggs of Marisa snails are also laid in clutches, but below the waterline, on vegetation. Depending on the temperature, eggs of either genera hatch after two to three weeks. The young will eat the same diet as the adults.
Land snails are functional hermaphrodites, with each individual having two sets of sex organs; testes, sperm and penis; ovaries, eggs, an oviduct and a pouch or receptacle for holding in reserve the sperm of another individual.
In rare cases, self fertilization is possible but normally mating is between two individuals of the same species.
Egg-laying follows in various locations including under logs and deep moist leaf litter.
SELF FERTILIZATION IS POSSIBLE BECAUSE...
Some snails are hermaphrodites, producing both spermatozoa and ova. Others, such as Apple Snails, are either male or female. Prolific breeders, snails in pairs inseminate each other to internally fertilize their ova. Each brood may consist of up to 100 eggs. Garden snails bury their eggs in shallow topsoil primarily while the weather is warm and damp. After 2 to 4 weeks of favorable weather, these eggs hatch and the young emerge.
Asexual reproduction is the type where only one parent is involved in the act and there is no fertilization required. In other words, there is no fusion of gametes. It is common to find this type of reproduction in single cell organisms. It is also a common phenomenon for plants and fungi. Typically, in other sexual beings, the offsprings get half of the chromosomes from each parent. However, in asexually produced living beings like snails, the division of chromosomes is unclear. This has confused the scientists, and they are unable to conclude anything about the characteristics and traits in snails.
Asexual reproduction of snails is still enigmatic for biologists. However, it is a known fact that snails study their mates and have a lengthy reproduction ritual where the mate has to prove several things. Most snails are considered hermaphrodites and there is proof of snails mating. However, in certain species of snails, asexuality or parthenogenesis has been observed. It is often difficult to tell if a snail has reproduced through normal sexual reproduction cycle or through asexual reproduction.
LOVE DARTS...
Another unusual, yet interesting aspect of snail reproduction occurs when species of the genus Philomycus eject calcareous “love darts” into their mates to stimulate copulation.
Cupid does exist, if only in the world of land snails!
Common snails, like all land snails, are hermaphrodites.Despite this they still need to find another snail to mate with. When two snails meet during the breeding season (late spring or early summer), mating is initiated by one snail piercing the skin of the other snail with a calcified 'love dart'. The exact purpose of the 'love dart' is not fully understood but it seems to stimulate the other snail into exchanging small packets of sperm. After mating is complete the snails will produce eggs internally, which are fertilised by the sperm that has been exchanged.
THE END
VDU timey !!
Enjoy!!!!
VIEWS :
This project took up so much of my sunday ... And I know this is gonna take up my friday too.. Sobsob.. my other needs are calling and i have not eaten yet!!!
Starvation is coming!!!
Dinner dad bring home also have to wait , so hungry...
The internet.. Other websites are just calling out for me to start on them. My heart, it can take not much more!!!
There was this videos I saw which is DIS-GUS-TING !!! The two snails were mating and the person in the video separated them apart and there was this gluey subtance ... And fadly's video on laying eggs .. so slow .. so pink!!! I did'nt know snails' eggs were pink in colour !!!
At least now i know snails' eggs are pink, the semen is this sticky, love darts are painful , snails do have courtship , I learnt that the sperms of the snails are stronger[longer lifespan].
There are alot of similarities and difference between the human and snail male!! Firstly, they must be not enough space.[Quoted from our dear Ms Nada] For human, the canal to recreational and sewage and the coiled epididymis. For snail male, the penis even have a sac to store it . Let me emphasise.... A COILED PENIS !!! Poor snails, must be hurting very badly other then the intercourse period..
well, one thing i must share, boys, all the way for your pull ups!! good luck!!
Actually, I eavedrop on a conversation and found out that to improve on this, you might want to train on your handstand, on the wall .....
But im still hungry...
In the future, i think that with this newly found knowledge, I will be a fool in snails reproduction for one moment than a fool for one lifetime.[Quoted from our dear Mrs Hon]
Sad thing i want to share.. Yesterdsay, after the NAPFA test, I rushed all the way home. I wanted to do my English homework but, {tak!} i fell asleep!!! At around 10pm did i woke up to bathe and packed my bags. By the time im done, 11pm.. Sob Sob ....>...< the next morning, i intented to wake up at 3.30am. But , Guess what ...? I OVERSLEPT!!! Sorry MrsHon..
had a quarel . okay, modification, afew quarels .. Ahhh.. The next word would'nt be CHOOO. Don't worry. I feel very tired even at this point of time...
yay!!! I just finally went out to take a small piece of chocolate the length of my pinky, the size of my tumb .. Hehehee.. So satisfying ..
I hope nobody would mind that Im putting everything into one post.. Im trying my best not to mix my post with the other two.... So... I hope using different colours will help...
Ohh.. I suddenly reminded of something .. I discourage underage & premarital sex. I''m sure many of you would agree with me right ? Like what Ms Nada said, [It's easy to hit the Jackpot]
and what's more is that we and animals are two different things. We can control and think before action comes out of you. Therefore, if one really knows how to think, you would definitely discourage this.
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