How does pollen know where to land?
Are all types of pollen accepted guests on all types of stigmas?
How about animals? What happens when a male of one species mates with the female of another species? Do we have a baby?
How To Soar in PSLE - BTPS Way!!
Interact with complex questions / graphs / pictures to pick up valuable clues (don't highlight - just use your pen to underline words or scribble notes)
Start with Booklet A and do it meticulously with full focus - explore all 4 distractors before making final choice.
MANAGE your TIME - to score well, you need to try to finish ALL questions.
Specific answers = answers that are relevant to question.
When confused, choose any of the following strategies:
1. Ask, "What Science idea is being used in question?"
2. Pose other questions to clarify your thoughts
3. COMPARE to another set-up
4. COMPARE to a reverse situation
5. Connect to your knowledge in life (yes, you do have lots of prior / other knowledge)
6. Break down your answer in steps before crafting final answer.
Common problems with wrong answers:
*Answers are generic/vague and do not connect to that specific question
*Answers are not scientific and do not explain using Science ideas
*Answers do not make use of data provided when asked
*Answers did not make comparisons - use words like more/most etc..when asked
BTPS supports all P6 in achieving their PSLE GOALS!!
Start with Booklet A and do it meticulously with full focus - explore all 4 distractors before making final choice.
MANAGE your TIME - to score well, you need to try to finish ALL questions.
Specific answers = answers that are relevant to question.
When confused, choose any of the following strategies:
1. Ask, "What Science idea is being used in question?"
2. Pose other questions to clarify your thoughts
3. COMPARE to another set-up
4. COMPARE to a reverse situation
5. Connect to your knowledge in life (yes, you do have lots of prior / other knowledge)
6. Break down your answer in steps before crafting final answer.
Common problems with wrong answers:
*Answers are generic/vague and do not connect to that specific question
*Answers are not scientific and do not explain using Science ideas
*Answers do not make use of data provided when asked
*Answers did not make comparisons - use words like more/most etc..when asked
BTPS supports all P6 in achieving their PSLE GOALS!!
Thursday, March 12, 2009
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Science Around Me (SAM)
SAM is a Science journal that allows pupils to express themselves in their favourite ways about Science.
SAM is another great opportunity for pupils to THINK and TALK Science in a medium that is customised to their learning styles.
SAM allows teachers to informally assess understanding of the child and clarify misconceptions in their learning.
SAM is another great opportunity for pupils to THINK and TALK Science in a medium that is customised to their learning styles.
SAM allows teachers to informally assess understanding of the child and clarify misconceptions in their learning.
Factors Affecting the Environment by Gog Ru Yan - 6G
When Ice Changes into Water by Goh Chee Yan - 5G
Do you wonder whether the mass of ice changes when it melts into water. Try this out:
1. Put a few ice cubes into a plastic bag
2. Tie the mouth of the bag tightly
3. Weigh the bag of ice cubes (if there is condensation outside the bag, wipe it dry before weighing)
4. Place the bag in the sun
5. When ice has melted, wipe the outside of the bag dry (refer to step 3)
6. Weigh the bag
You will discover that the mass of the bag remains the same!
There is no change in mass when ice melts!!
1. Put a few ice cubes into a plastic bag
2. Tie the mouth of the bag tightly
3. Weigh the bag of ice cubes (if there is condensation outside the bag, wipe it dry before weighing)
4. Place the bag in the sun
5. When ice has melted, wipe the outside of the bag dry (refer to step 3)
6. Weigh the bag
You will discover that the mass of the bag remains the same!
There is no change in mass when ice melts!!
Simple Steps to fight Dengue by Elizabeth Wu 4C
38 comments:
- Well , actually , pollen does not know where to land . They are transferred from the male part of a flower to a female part BY WIND OR ANIMALS (not themselves).
- Yes , they are accepted . They will create a mix-species flower with the ovule ,the flower is most probably to carry characteristics of both of the flowers .
- For animals , I am not really sure but well , this blog is to express ideas . As for animals , I think what will happen is that there will still be a baby produced but it is a cross-bred. For example , I have read that a male dog that is of a different species when mates with a female dog of another species , they produce a crossbred . The same happens to fish .
Yuling =)
My thoughts are nearly similar but it is actually happens in a different way. Pollen does not Land like where they want to, we learnt that pollen actually uses different modes. It is more probable by wind than other forms(Probably the cost of hayfever) And animals like bee which are also called pollinators. With only a few exceptions. For the second point, it may not choose, the DNA chooses. It is rare to crosbred flowers of different genus (You may go find Carolus Linnaeus for this terms) if they have the chromosomes that are interchangable, it may mix and the microgametophytes will mix with the ovum to form a seed. Finally, it seriesly do depend on its genus. If they are the same , most likly it will have a baby ( A egg sometimes)
Pek Yu-Xuan Sean
Some of them can like the mule. It's the offspring of a male donkey and female horse - two different species. In order for different species to be able to breed, they must be closely related - usually within the same genus, and at least within the same family. Donkeys and horses both belong to the family Equidae and genus Equus.
To finish off what I previously said about cross-mutation since the third blogger actually state something about a mule. Well, we cannot count that in as in it force mutation, the offspring is likly to be infertile so it is possible but unlikly in the nature's way. These wierd offspring are the cause of human interference.
Pek Yu-Xuan Sean
You should tell us where the pollen grains will land.
Actually the pollen does not know where to land.I think they just land where there is a stigma.Yes...i think that they will land on any types of stigma.The flower's baby will have the characteristic of both flowers.
Oh...i am sure that a male of one species, can mate with another species,that is quite a similar group.(Later you will know what it means.)I have see one before.The baby will look more like the father.
I went to Korea,south korea and we went to their zoo.We went around the zoo with a bus.On the way,the tour guide tell us that he has a surprise for us to see.
Then, the bus stopped.The tour guide pointed outside.We looked and saw a lion and tiger and their baby.The baby looks like a lion,as the father is a lion and a bit like the mother,the tiger.
The tour guide told us,"The zookeepers here put the lion and the tiger together.After a while, they started to mate,then, they borned that animal.It is called a liger."
So i believe that a male of one species can mate with another in a similar group,like the lion and the tiger are so called big cats.
Rachel Neo--6 Faith
the pollens can be accepted by all stigma's,only that the plant might have differnet colours of types.
Actually, i think that pollen does not know where to land. they dont pollinate by themselves. they get pollinated by , most commonly, wind and animals.
For the second question,i think that,yup,they are accepted.They will make a combined species flower with the ovule.
For the third question, i think that im not so sure but i think that they will still have a baby but it might be disfigured or cross-bred.
Farid 5C =P
Pollen do not know where to land. They are carried by wind or animals to the stigma of a flower.
Pollen are accepted on all types of stigmas and will create a mixed-species flower together with the ovule.
~ I think that pollen does not know where to land as it is transferred from the anther to the stigma by wind or animals(most common).
~ Yes. They will make a new species of flower with the ovule.
~ I think they will still have a baby but it might be a cross-bred.
~ Andrea Tan 5C =D
I THINK(its only my own opinion) pollen know where to land. Because inside every pollen there is vegetative (non-reproductive) cells. And as we know, cell is a living thing (Did i get my concept mix up?)No I didn't.\
SO I think the cell will go according to smell or any other factor to go to the place it wants to go.
I think all kind of pollen are accepted. Because there are many different 'weird' animals like animal's cell come in contact with a SIMILAR animal's cell, it can still have a baby which looks like them.( thats what i read in some books) And when that happens, they will create a mix-species flower and the flower have a very high chance of carrying some of the characteristics of both of the adult flower.
For animals, the answer is a big YES. But they must be very closely related and in the same family. I will give some examples.
Horse and Donkey YES
Lion and Tiger YES
Horse and Zebra YES
jack and Mare YES ( they will create a mule)
Bull and Baffalo YES
Cat and dog NO
Marcus Chioh
Look like I still got some mis-conceptions,simply saying summerising the first problem with a few words.
Cross-Bred Animals with human interference is not a species, It does not have a healthy offspring or one that can continue to reproduce.
Charles Darwin is a evolutionary thinker and said that nature have it's own way mutation, but force bred is not, it can't continue to reproduce!It is true that animal of the same genus can be force with human interference can be bred but they are not a species.
Liger,Mule..etcetra, thay are not species.
Then Pollen have it's method of landing, the shape can actually affect it.
But other than that, not much else.
Pek Yu-Xuan Sean
When a male of a species mate with a female of another species, they will have a baby which is called a sterile.example a tiger mating with a lion will produce a linger.But this sterile cannot reproduce.this can also only happen when both animals are 'close'.
But as for pollen i have no idea.
Sry i forgot to type my name.post13is by
Pauline.
-Pollen do not know where to land. Pollen use agents such as wind,(very rare)water, pollinating inscets and animals. They may even self pollinate. This way, the pollen from the stamens reach the female part of the flower, the pistil. The tip of the pistil is the stigma. The pollen lands on the stigma. Once it arrives at the ovary it fertilises the egg (ovules).
Then the ovary begins changing. Simply, it becomes the fruit around the seeds. The seeds are the only part that are the result of the union between the male pollen and female eggs.
-I am not very sure of the second answer, but what i know is that flowers have specific designs which encourages the transfer of pollen from one plant to another of the same species. Many plants are dependent upon external factors for pollination, including: wind and animals, and especially insects. Even large animals such as birds, bats, and pygmy possums can be employed. The period of time during which this process can take place (the flower is fully expanded and functional) is called anthesis.
-I think that there will still be a baby produced. As some people already stated, dogs are able to crossbreed and so are fish. These produce new unique species of dogs, which can sometimes be suited for people with special conditions.
Joy Peh, 6Charity
Cros Breeding Pure breds of dogs may have more advantages, but it does deafeat the purpose of Mother Nature's natural selection. Then, this cros-bred will be sterile, like Pauline states. Then the bred is not able to reproduce. Anyway has read the question, it's say same species.
Pek Yu-Xuan Sean
- I think that will still be a baby. An example are the dogs. Different species will still be able to have a baby -- it will be a mix breed. The should apply for other animals.
- Pollen does not know where to land. Like some of you said, pollen grains are carried from one flower to another by either wind or animal and not by themselves.
Megan, 6Faith
I agree with Joy except the part when she said that pollen do not know where to land.
And Megan can you please make your comment more clear."Different species will still be able to have a baby -- it will be a mix breed. The should apply for other animals."
This statement can only be used for similar animals and some other animals cannot. So please be more scientific because not all species can have a mix breed. And only SIMILAR animals can have a mix breed and that mix breed cannot reproduce
MARCUS Chioh 6G
- The pollen does not know where to land. They are transferred from the male part (anther) of the flower to the female part (stigma) by either wind or animal.
- In my opinion, only some -those which are of the same genus- will be accepted.
- As for animals, both the male and female animals must be pure bred so that they will be able to crossbred. Animals which are born from different species are usually sterile.
-How does pollen know where to land?
Pollens do not know where to land. They use agents such as wind, water(very rare) and insects or even animals. If you read 'horrible science-horrible experiments', you will be able to read that one of the scientists found out that his mucus contained pollen grains. That tells us that pollen grains cannot control. Well, if you still say that they control their way out, do you hope to go inside one's nostril and be wet with mucus if you were a pollen grain? (sorry, I know it is disgusting)
- Are all types of pollen accepted guests on all types of stigmas?
-Unlike other pupils, I do not think so. Since pollen grain do not know where they are going, uncountable number of pollen grain must be floating in the air and all the pollen grain cannot be of the same species (don't tell me you don't agree with me...^^) and let's assume that the main character-pollen grain is an orchid's pollen grain that I am talking about.
This pollen grain of an orchid landed on a morning glory's stigma. Well, not in purpose, of course and you do know that there must be pollen grain of other species. However, if all those pollen grain of different species are accepted, where are those beautiful flowers that are 100% its species that we see in the florists' hands?
As the nucleus of the pollen grain of this flower and the ovule try to make it a seed, the chromozomes of the two become a pair. However, do you think that the genetic information present is the same as each other? All right, let's just assume you disagree with me, let's just assume that all pollen grain of different species and the stigma can reproduce. The different genetic information adds up together and the cross bred looks like half orchid and morning glory. Where do you think you can get the beautiful flowers from(100% its own species)? I mean, do you actually think that you can see them in this world?
In Korea, we give our parents beautiful carnations on parents' day. And when there is no carnation which LOOKS LIKE CARNATION, I will be very sad. I used to save so much money for it. Anyway, back to the point, these points make me think that all types of pollen grain are accepted by all types of stigma.
I wish to explain how plants can 'lure' animals to pollinate them to the same plant, like being close to other plant so that the pollinator do not have to travel far to get more nectar, making the pollen land on the plant. And, in severe case of cross pollination, where plants of different genera but the same family can cross pollinate, i really heard a mass-populating plant created by mixing plants of different families.
In the case of the family of orchidaceae, they actually can cross breed, and form new species, if i am not wrong, they actually do it with corn samples as well.
Pek Yu-Xuan Sean
Youn Yea Won (6C)
Well, I actually agree that I've seen a mix breed dogs, like my mom's friend's, it is born from a different type of dogs but a same type of species, dogs. Therefore, this tells us that the different types of the same species can give birth to a mix-bred!
ellia, YOU ARE CORRECT but I have seen a numbers of flowers that look like 2 flowers together. THX FOR LETTING ME KNOW ABOUT THE MUCUS part (its not digusting). Since Mucus are sticky, maybe the pollen grains when travelling to another flower got stuck there? You may never know.
"Where do you think you can get the beautiful flowers from(100% its own species)? I mean, do you actually think that you can see them in this world?"
MAYbe most of the 100% flowers are self pollination? So they can 100% have the same species because the pollen need not need to go to other flowers. Many flowers also self-pollinate so the 100% flowers may come from flowers that self-pollinate. And for the carnation part, I think they plant the carnation in a room for the korean festival to ensure that they are carnations and not mix species?
MARCUS CHIOH
Species as Carolus Linnaeus defined it is that same DNA, same features and the identical habit. It is impossible to have the identical species giving birth to a mutant. Lets take homo sapiens for example. A male and a female can give birth to a same species but have a bit of differenrs. That is due to the reccesive chromosomes.
Pek Yu-Xuan Sean
sEAN. what you say is like very hard to understand, do you mind if you make the words simplier so that everyone can understand? thanks
marcus chioh 6g
Marcus,
What you have said, I don't think it's correct because I don't think the 100% its species those flowers are not self pollinated. I mean, then where are the rest, the cross pollinated flowers? We have learned in p5 that flowers can both self-pollinate and cross-pollinate.
Sean,
Thanks for letting me know about Carolus Linnaeus defined it is that same DNA, same features and the identical habit thing. For the same species giving birth to a mutant thing that you are talking about, I was meaning let's say there is poodle and Si Tszu(I don't know how to spell, sorry). They gave birth to funny looking dog that blends the characteristic of both dogs. I was meaning that. Not two poodles giving birth to
a mutant. Sorry for misleading comment.
The pollen does not know where to go. Wind dispersed pollen must land on the same species of flowers to germinate the pollen tube. Insect pollinated plants needs the help of insects to transfer the pollen grains from the anther to the stigma. For some species, if they do not land on the same type of plants, the pollen tube will not germinate. Some, however can cross breed.
For animals, I think they might be able to crossbreed(provided they are the same type of animals.) Some might not be successful though... ...
Samuel Tay
"What you have said, I don't think it's correct because I don't think the 100% its species those flowers are not self pollinated. I mean, then where are the rest, the cross pollinated flowers? We have learned in p5 that flowers can both self-pollinate and cross-pollinate." ellia
I did not say that all the 100% flowers you saw was self-pollinated. I said MOST maybe about 80% and the rest the pollen got to land in the correct place so please understand properly
MARCUS CHIOH 6G
Pollen may not know where to land but they are actually transfered through the wind or animals according to what i've learnt.
Pollen do not actually know where to land. If there is such a thing, then won't there be overpopulation of plants?
*If you ask me...Yes, I think that the pollen grains are accepted. I think the pollen grains would land on any type of stigma and the flower produce would carry characteristics of both flowers.
*For animals, I'm not so sure. But I would say, YES, they would still have a baby but the baby might be what we call "DISFIGURED" or most probably cross-bred.
Renise Ngo (5C) >.<
Pollen grains do not know where to land because they have no sense of sight. They will land wherever their pollinators take them to.If,unfortunately,they land on an empty ground with nothing to reproduce with,they will be left there forever.
If pollen grains from the anther of an orchid plant lands on the stigma of a morning glory,the offspring will have the characteristics of both plants.
Animals will tend to stay in their own colony and mate with the opposite sex of the same species.e.g.a lioness will mate with a male lion. But there is a likelihood of animals of different species mating.Like this for example,a jaglion(offspring between a male jaguar and a female lion.)
i think that pollen does'nt know where to land cause it depends on which place the insect or wind takes the pollen to.
Sally 6G
is it possible for example for a cow and a horse to mate and have
offspring. The classical example of interspecies breeding is
ofcourse the mule, from a horse and a donkey. Other
examples are tigers breeding with lions to produce
'ligers', and sheep with goats. In all of these cases
the species are close enough to allow breeding, but
the offspring is sterile
Sally 6G
i think that it(the pollen) just goes with the wind and accepts where it lands. it will then develop into a mix-species flower. like,say,dogs.they also have cross breeding like the flower.
Yi Rui 6Grace
pollen does not know where to land it actually glides through the wind or it is transferred by animals. all types of pollen are accepted by stigma. when one species mates with another species i think that there were be a baby produce but a very different one jd
pollen do not know where to land as it is dispersed by wind ,animals,water ect.so maybe they will create mix species flower .
maybe there will be a baby but i think it would have both heredity from their parents and made them cross-bred
Kelvin Ruty (6G)
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