So...was asked to research about snails and the way they reproduce for biology e-learning. 1st thing came into my mind: YUCK! X_X snails are one of the most disgusting thing on earth despite being the slowest D= . Its must be very random for Ms.Nada to come up with such idea =X
So I did my research.
1st of all, Snails are hermaphrodites and I was like, "EH?!?!" because I seriously didn't know about that. Well, I never know because I seriously don't bother knowing about snails =S I don't even want to think about them. So, they are hermaphrodites, which means, they still do sexual reproductions, but they are not picky between male or female.....or...
XD XD
Okay, so what do they actually do when they are mating? From what I found, they have a around six hours of marathon of rubbing, biting and "eystalk" waving...to me, sounds just like what we humans normally do when we are mating, just that snails do it super slowly(no doubt that they are the slowest on earth =.=)...which is why they takes hours...
During the process, they actually have this thing called "love dart" injected into each other which actually contain sperms. And it pierces right through each others skin...ouch! And then all the fertilisation occurs within both snails. Sperms combine with ovum, yada yada just like other sexual reproductions...=)
Then comes the eggs, and the fantastic yet disgusting thing is, snails' skin are transparent, which means..you can actually see eggs moving in the snail!!! D: I mean it, watch....
OMG rite?? @@
And different species of snails lay eggs at different places. So there is lots of variation. These eggs hatches after around 2 weeks or so.( At least this fact of snails are not exactly disgusting =S ) After hatching, the baby snails, find their calcium as soon as possible, mostly by eating their own eggs. Then it takes around 3 months for the snail to develop and ready to leave its nest and parents. Then the snail develops, become a adult snail, reproduce, and the cycle keeps going on and on.
So, Snails are actually very unique in their way of reproduction, but still disgusting D=. But there comes the fun of learning and knowing new things =). Now I can boast to others when we see a snail and talk about how they reproduce XD
God really create many special and unique things in this world =)
Well, many of us have seen snails before...
Either in the morning while walking to school or near dam areas
I had once encountered with snails before, but it ended tragically...
I was walking to school one fine morning... and found that the path way is occupied by snails. -Sigh- So I tip-toed my way across, to avoid crushing them. As I make my move, I noticed a particular pair... I wondered what are they doing and why? So i looked closer, "intersting" was the fist word... I was too engrossed looking at one and -CRACK- i accidentially steped one snail behind me...
I was curious, so i did my own research... and suprisingly, snails are amazing creatures...
To start of, Defination of a Snail: Any species of gastropod mollusk with a shell that glides along on a broad tapered foot and has a high coiled shell into which it can withdraw.
Some facts of Snails; The life span of a snail is about 5 to 10 years. They come in differen in shapes and sizes...
Snails are found in the ocean, in fresh waters, and on land. Most snails are marine and marine snails have gills in the mantle cavity. Most land and freshwater snails have no gills; they use the mantle cavity itself as a lung. Snails may be either scavengers (of dead plant or animal matter) or predators.
Snails eat plants with their tongues. There are thousands of tiny teeth on a snail's tongue, or radula.This is a chitinous ribbon bearing teeth which is moved over a supporting protrusible “tongue” with a to-and-fro action.
The radular apparatus has a twofold function: it serves both for rasping off food material (mechanically like an inverted version of the upper incisor teeth of a beaver) and for transporting the food back into the gut like a conveyor belt. A snail also grinds up small pieces of rock with its radula to get minerals it need for a strong healthy shell.
Interesting, don't you think?
Lets get back to the topic...
Well...
Most snails (prosobranchs) have separate genders and generally practice internal fertilisation. Some species of snails are hermaphrodites although they may act as a male or female at any one time. When two snails meet, they typically exchange sperm. Most gastropods lay eggs in a case, capsule or in gelatinous strings and masses.
When two snails meet and that the season of the loves, they begin by kisses: those are the preliminaries.
But the snails doesn't go directly from these preliminaries to copulation.
The snail, next to its head, has a muscular pouch. This muscular pouch, at a moment of the preliminaries, open and release a dart, an arrow, then, Cupid's arrow.
This arrow will go and get imbedded between the head and the shell of the partner. And this... the fact of being pricked by this dart, by this small arrow, will bring they to copulate.
Scientific investigation recently revealed that the "dart of love" is rather a means of injection. By using this dart, the snail giver injects at the recipient a mucus containing several types of hormones.
These hormones affect the genitals organs females of receptive snail.
They will emerge their penis from we don't where, but generally under the right eye. Then, our two accomplices exchange their small bag, called spermatophore, containing the spermatozoa.
By the miracle of biology, our two male snails transform themselves into female, to produce ovules, which will be fertilized by the stored spermatozoa of the partner. This act will last several hours (approximately 10-15).
There 15 to 20 days later, the snail will dig a hole of a few centimetres of deep. The quantity of eggs layed is approximately a hundred (that depends of the race, the age, etc...).About two weeks after mating, the snail scrapes a hole in the soil and lays its eggs there. A snail lays between 20 and 50 eggs at a time.
The eggs are covered up and they hatch after about four weeks.
VIDEO TIME!!!!
Well...
Let me start of with the project...
To me, this project is refreshing.
The topic was unexpected, but interesting indeed!
It had never crossed my mind before.
Well i guess that we are usually in a rush...
We dont see any significant in this small creature, but in a matter of fact...
If were to follow the trails of the snails, there is a lot that we could learn...
Like the song "Colours of the Wind" from the movie Pocahontas...
You think the only people who are people
Are the people who look and think like you
But if you walk the footsteps of a stranger
You'll learn things you never knew you never knew
Ya, other then watching an hour and a half of "how the snails Reproduce"...
(Which is like Super SUper SUPer SUPEr SUPER Slow)
I guess that is how Mother Nature works...
I would also wold like to cogratulate Ms Nada to be the first to use blogs as a way of approching things. In the matter fact that no other teachers, that i know, encorage students to do projects/reports by blogging.
Snails are the slowest animal in the planet.Most people dislike snails due to their slimy attribute. However, one thing fascinating about snails is its way of reproduction.
If you are entering into the wild world of snails, you will also begin to notice that the way in which they are built has allowed for their survival through centuries. One of the ways in which this has continued to build is through the abilities to reproduce by these creatures. The different features and ways in which they can do this also provides them with the capacity to keep slugging on the land.
Reproductive Make-up of Snails
Snails will be able to reproduce differently than almost any other type of creature because of their species and their make-up. This begins with the build that all snails have. Snails are considered to be hermaphrodites. This means that every snail will have both male and female reproductive organs. This is especially consistent among land snails and most marine snails. The only snails that have not adapted this attribute is some freshwater and marine species, specifically including Apple Snails and periwinkles. These two types of snails still have a separate male and female species.
SNAILS LAYING EGGS
All snails will be considered sexually mature by the time they are one year old. This is because the life span of most species does not last for more than five to seven years, allowing for a faster growth rate of the species. The make-up of the snails will include their reproductive organs on the side of their body. This is close to the top of their body as well, allowing for easier abilities to mate and to grow the baby snails.
Growing Into Baby Snails
The mating practices of snails is one that allows for new snails to be brought into the dirt and water at a consistent rate. Snails will go through a complete mating ritual with each other, usually which will communicate to the other snail for an average of two to twelve hours. At the end of this ritual, the pair will fertilize the eggs in the other. It is known that a snail can carry up to 100 eggs at a time.
When the eggs are fertilized, they will go through a process of growth inside the snail. This begins with the fertilization moving the snails into a specific amount of development inside the embryo. This takes place with the snails laying eggs and burying them into a cool place in order to develop. For land snails, they will be buried underneath the dirt in order to be cared for. With marine snails, the eggs will be placed next to a solid area, such as a rock. This will allow the eggs to stay in the same place and develop without being harmed.
It will typically take a snail egg two to four weeks in order to develop. As soon as they hatch, they will immediately move into a survival mode. This is because their shells will still be in a weak form. Their reaction is to find calcium as soon as they hatch by either eating their own egg or eating other eggs in order to get the extra nutrients. It will take around three months for the snails to completely form. While this takes place, they will stay in a nest that has been built for them, with the transformations being seen through a change in color, from a clear color into a blue then into the adult form that is representative of the species. After the snails are completely developed, they will detach from their parents and move into a different shell.
The mating procedures of snails is one that moves through a specific process that helps the species to grow and survive in their respectable areas. From the beginnings of sexual maturity to finding the rate mate to the hatching of the eggs, is a specific way in which the snails are able to move into a world of growing a larger snail family.
Now, the thing is, how do they actually do it? As in, having sex?
Snail reproduction is a curious tale. Snails are hermaphrodites, but although individuals contain both male and female sex organs, they do not self-fertilize. The two to six hour marathon session that is snail copulation is actually an exchange of sperm between two individuals, combined with plenty of rubbing, biting and 'eye-stalk' waving. Individuals use the received sperm to fertilize their own eggs — a process that is necessary to maintain genetic diversity in the population.
The exchange of rubbing,bitting and "eye-stalk" waving
What makes some snail species particularly interesting to is their use of 'love darts' during copulation. About one third of snail species manufacture hard, sharp darts which they 'fire' at the object of their affections (i.e. other snails).
An illustration of the "love dart"
It was incorrectly believed that these darts were a nuptial gift of calcium —a major constituent of snail shells—from one snail to another. Like a bunch of flowers or a box of chocolates in humans.Another belief was that the dart was intended to arouse the receiver and indicate the shooters readiness to mate.
However, those are only beliefs. There are scientific researches done.Basically, snails want to reproduce as much as possible. Snails that have a way of ensuring that their sperm, rather than another's, is used to fertilize eggs will therefore sire more offspring. This is known as sperm competition.
The love dart is a tool of male manipulation. Received sperm is moved to a storage area within the female reproductive system where it is used to fertilize eggs over a period of months or years. However, many sperm fail to reach the safety of the storage area and are instead digested in great numbers en route. Research conducted revealed that of the millions of sperm received by a snail, only 0.025 percent actually survive. Love darts contain mucus that temporarily contracts a part of the female reproductive system in a way that allows a greater number of sperm to reach the storage area and survive; In short, 'he shoots….she stores.'
Being hit with a love dart may increase the survival of sperm, but fortunately for some snails it is not essential for copulation. Poor shooting is commonplace— one third of all love darts either fail to penetrate the skin or they miss the target completely.
Being hit with a love dart may sound cute and comical, but for the recipient there may be costs. Love darts are the equivalent of being stabbed with a hypodermic needle. Evidence from mating trials conducted in the labs indicates that snails try to avoid being hit with love darts. Copulating snails are commonly seen jostling, in an attempt to hit but not be hit. But, all is fair in love and war.
Snails seriously have very unique way of reproduction.
In spring, when the Roman snails have been awake from hibernation for some time, it becomes time for mating. Depending on the weather and other environmental conditions, mating time may last until the end of June. Only until then the juveniles will have enough time to prepare for hibernation so they are able to survive winter.
REPRODUCTION SYSTEMS
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) of 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.
Research Aim: to learn about different parts of a flower and the types of reproduction systems of plants.
Introduction
Botanical Garden( place of research)
Why Botanical Garden?
1st founded by Sir Stamford Raffles, also the founder of Singapore at 1822. Its purpose was to introduce cultivation of economic crops. However, it was closed down in 1829 due to insufficient funding and lack of proper management after Raffles's death.
It was then in 1859 the garden were founded at its present site as a leisure park and ornamental garden by the Agri-Horticultural Society. The garden then undergoes many other developments over the years and now it is under the continued stewardship of Dr Chin as well as becoming a important and popular tourism site in Singapore.
The garden have a linear distance of about 2.5km between the Northen and the Southern end.It is divided into 3 zones that is the Bukit Timah Core, Central Core and the Tanglin Core. The map of the whole Botanical Garden can be viewed at www.sbg.org.sg/visitorinfo/mapofgroud.asp
In Botanical Gardens, you can find thousands of type of flowers and even some of the rarest species of flowers are found here. Other than the huge diversity of flowers, the popular heritage tree well known in the whole Singapore, the Tembusu tree, with a special feature of a distinctive low long branch which has become a popular spot for people to sit on and take photographs. The image of the Tembusu is also found behind the Singapore's 5 dollar note
The Tembusu Tree
There is no other place more suitable than the Botanical Garden in Singapore if you were to research on flowers and plants.
Flowers( findings before the trip to Botanical Garden )
What are flowers?
Flowers are actually the reproductive structure of a flowering plant(also known as Angiosperms). Flowers are usually both male and female, and are highly brightly coloured to attract insects to help them carry pollen used for sexual reproduction( insect pollination ).Some are not colourful as these flowers normally uses wind pollination.
Structures of a flower Stamen - male part of the flower. Consist of :
Anther- produces pollen grains
Filamen- the stalk that holds the anther in a suitable position to disperse the pollen.
Carpel - the female part of the flower. Consist of:
Style - stalk that connects stigma to the ovary
Stigma - swollen structure at the end of the style that receives pollen grains
ovary- contains one or more ovules which contains the female gamete(ovum)
Petal - modified leaves formed on the most conspicious part of a flower.
Sepal - modified leaves which enclose and protect the other parts of the flower in the bud stage.
Receptacle - enlarged end of the flower stalk which bears the other parts of the flower.
Is a type of epiphytic orchid.Cattleya orchids are one of the most popular kinds of orchids. The beautiful form and the complexity of the flower and their alluring scent have won the hearts of many.
The cattleya orchid is a monocotyledon angiosperms. Its is pollinated by insects. This is why it has a sweet scent to attracts insects. The insects will then help to transfer the pollen grains to the female part of the flower.
The stigma of the cattleya orchid, in fact, all orchid have 2 important roles. The seperate the anther from the mature part of the mature(fertile) part of the stigma to prevent self-pollination. The other role, which involves a part of the stigma called the viscidium, a sticky pad, when touched, it quickly adheres so that as the pollinator(insect) backs out of the flower the entire pollinarium is removed with it.
Plumeria "Donald Angus" (Frangipani)
The Plumeria or Frangipani is a insect pollinated flower.
Plumeria flowers are most fragrant at night in order to lure sphinx moths to pollinate them. The flowers have no nectar, and simply dupe their pollinators. The moths inadvertently pollinate them by transferring pollen from flower to flower in their fruitless search for nectar.
Taberbaemontana divaricata
Also commonly known as the Crape Jasmine or the pinwheel flower.Crape jasmine is an attractive evergreen tree with green twigs and milky sap. The shiny, opposite, dark green leaves, 3–6 inches long, are ovate and pointed, narrowing into a short stem that clasps the twig. The white, waxy flowers with five or six lobes are 1–2 inches in diameter. They have some fragrance at night and are produced most of the year.
Like many other flowers, it is a insect pollinated flower. Its fragrance and attracttive petals attracts insects.
Alpinia Purpurata ( Red Ginger )
The red ginger are native Malaysia plants with showy long flowers on long brightly coloured red bracts. They look like the bloom, but the true flower is the small white flower on the top.
It is a insect pollinated flower with the features of attractive looks to attract insects. Sometimes its also attract spiders.
Heliconia psittacorum x Heliconia spathocircinata( Golden Torch )
Heliconia is a insect pollinated plant. Its bright and attractive colour attracts animals and insects.
It is also a important food source for forest hummingbird. Sometimes it is even used for nesting. The Honduran White Bat also lives in tents that is made from heliconia leaves.
Reflection
After doing the research, it has helped us a lot by knowing how different plants have different ways of reproduction system. It is also very fascinating to know that all flowers have their own unique way to attract insects or adapt to the nature.
Besides that, we also get to know the chapter of reproductions of plants better by doing such research and have self discovery. It may a better and more effective to research ourself rather than to let the teacher teach the topic to us.
We also learn that teamwork is important after the research. During the trip to Botanical Garden, we almost lost our way back but everyone played a part on remembering the direction that we came from. This also tells us that we need to trust our teammates and not just be selfish and ignorant when we are working as a team.
Other than that, we also learnt that nature is a very beautiful thing. During the trip, the garden which was full with forest smell and clean air really makes anyone feels refreshed. On top of that, we get to see many breathtaking natural sceneries. After this trip, we all felt that to keep the environment clean and to save and conserve nature is something really important. It would be very cruel and unfair if the next generation is unable to see all the nature's beauty.
This was in fact the best research based trip that all of us have ever had.
Credits To
Ms Nada & Ms Tan!!!!!
without them, there will be no trip and all of us will just have to stay and stuck in a boring class looking at the boring textbook!
.jpg)
.jpg)
.jpg)
.jpg)
.jpg)
