Friday, 31 July 2009
Just joking........
Calvin
What school rule will I break?
By:Qiu En
What school rule will i break if I can
Glen
what school rules I want to break if I can.
break the rule for reaching to school on time. Then,
I will sleep till I'm satisfied and then I will
take a morning stroll then I'll go to school.
If it's raining, I will not go to school.
BY,YI RU
If I can break a school rule.......
Calvin (Calbee, called by Joelvin, BABA called by Gareth, Calcium called by Xue Feng, or Mr Shitty called by Pei Zhen)
what school rule would l break if i can?
JieYi
Thursday, 30 July 2009
what school rule would i break?
mavis
which school rule will i break??????????????????????
information on capillaries... by gareth
Blood flows from the heart to breast, which branch and narrow into arterioles, and then branch further still into the capillaries. After the tissue has been perfused, capillaries join and widen to become venules and then widen more to become veins, which return blood to the heart.
The "capillary bed" is the network of capillaries supplying an organ. The more metabolically active the cells, the more capillaries it will require to supply nutrients and carry away waste products.
Metarterioles provide direct communication between arterioles and venules and are important in bypassing the bloodflow through the capillaries. True capillaries branch mainly from metarterioles and provide exchange between cells and the circulation. The internal diameter of 8 μm forces the red blood cells to partially fold into bullet-like shapes and to go into single file in order for them to pass through.
Precapillary sphincters are rings of smooth muscles at the origin of true capillaries that regulate blood flow into true capillaries and thus control blood flow through a tissue.
TYPES
Capillaries come in 3 types:
Continuous - Continuous capillaries have a sealed endothelium and only allow small molecules, like water and ions to diffuse. Continuous capillaries can be further divided into two subtypes:
1.Those with numerous transport vesicles and tight junctions that are primarily found in skeletal muscles, lungs, gonads, and skin.
2.Those with few vesicles and tight junctions that are primarily found in the central nervous system.
Fenestrated - Fenestrated capillaries (derived from "fenestra," the Latin word for "window") have pores in the endothelial cells (60-80 nm in diameter) that are spanned by a diaphragm of radially oriented fibrils and allow small molecules and limited amounts of protein to diffuse. In the renal glomerulus there are larger fenestrae which have no diaphragms. Both types of fenestrated blood vessels have continuous basal lamina and are primarily located in the endocrine glands, intestines, pancreas, and glomeruli of kidney.
Sinusoidal - Sinusoidal or discontinuous capillaries are special fenestrated capillaries that have larger openings (30-40 μm in diameter) in the endothelium to allow red blood cells and serum proteins to enter, a process that is aided by a discontinuous basal lamina. These capillaries lack pinocytotic vesicles and gaps may be present in cell junctions permitting leakage between endothelial cells. Sinusoid blood vessels are primarily located in the liver, spleen, bone marrow, lymph nodes, and adrenal cortex.
It also transports blood to cells, and it is very thin.
PHYSIOLOGY
The capillary wall is a one-layer endothelium so thin that gas and molecules such as oxygen, water, proteins and lipids can pass through them driven by osmotic and hydrostaticification intercontinentalingradients. Catering products such as carbon dioxide and urea can diffuse back into the blood to be carried away for removal from the body. The physics of this exhange is explained by the Starling equation.
The capillary bed usually carries no more than 50% of the amount of blood it could contain, although this amount can be increased through auto regulation by inducing relaxation of smooth muscle in the arterioles that lead to the capillaries bed as well as constriction of the metarteriole. d capillaries (derived from "fenestra," the Latin word for "window") have pores in the endothelial cells (60-80 nm in diameter) that are spanned by a diaphragm of radially oriented fibrils and allow small molecules and limited amounts of protein to diffuse. In the renal glomerulus there are larger fenestrae which have no diaphragms. Both types of fenestrated blood vessels have continuous basal lamina and are primarily located in the endocrine glands, intestines, pancreas, and glomeruli of kidney. Sinusoidal - Sinusoidal or discontinuous capillaries are speci The capillary do not possess this smooth muscles in their own walls, and so any changes in their diameter is massive. Any signaling molecules they release (such as endothalen for constriction and nitric oxide for dilation) act on the smooth muscle cells in the walls of nearby, larger vessels, e.g. arterioles.
Capillary permeability can be increased by the release of certain cytokines, such as in an immune system.
Starling equation is a mathematical model for fluid movement across capillaries:
where:
Jn = net fluid movement between compartments (ml/min)
Kq = Filtration coefficient (ml·min-1·mmHg-1).
Ph = Capillary hydrostatic pressure
Pu = Interstitial hydrostatic pressure
πk = Capillary oncotic pressure
πp = Interstitial oncotic pressure
σ = Reflection coefficient
HISTORY
Ibn al-Nafis theorized a "premonition of the capillary circulation in his assertion that the pulmonary vein receives what comes out of the pulmonary artery, this being the reason for the existence of perceptible passages between the two."
Marcello Malpighi was the first to observe and correctly describe capillaries when he discovered them in a frog's lung in 1661.
HOPE THIS HELPS MY CLASSMATES AND TEACHER!! :D
which school rule will i break?? by GARETH
Which school rules would i want to break?
Which school rule will I break?
If I get to break a school rule, what will it be?
Which school rules would i want to break?
If I get to break a SCHOOL LAW what will it be?
Tuesday, 14 July 2009
P5 NE show experience. ERVIN CHIA
Monday, 13 July 2009
how do dolpins sleep in water?
UNDER TOW. A baby humpback whale eats and sleeps while being pulled along in its mother's slipstream.
When marine mammals sleep and swim at once, they are in a state similar to napping. Young whales and dolphins actually rest, eat and sleep while their mother swims, towing them along in her slipstream--a placement called echelon swimming. At these times, the mother will also sleep on the move. In fact, she cannot stop swimming for the first several weeks of a newborn's life. If she does for any length of time, the calf will begin to sink; it is not born with enough body fat or blubber to float easily.
ne show
mavis
---The NE show---
Zahirah
ne show experience! =)
n.j.x
Jolice's experience in the NE show
NE show experience
There were parachute performance, dance from different organizations,parade, aeroplane show. The NE show was interesting. Although it rained heavily, we stood up to recite the pledge and sang the National Anthem. We saw fireworks and we felt happy. All of us were wet and shivering in the bus on the way back to school.
NE show
By:
Thiren
How dolphin and whales sleep
are just like we are, wouldn’t they drown if they were to fall asleep in the ocean?The answer to that question is obviously no considering dolphins and whales are very much still alive.There is involuntary and voluntary breathing. We humans are involuntary, which means that if we do not breathe, our bodies will automatically try to induce air. Since dolphins and whales have a unique respiratory system which allows them to hold in air for a long period of time, they are voluntary breathers. Voluntary breathers are also known as conscious breathers, which simply means that they need to be conscious in order to breathe because they control when to and when not to breathe.
Ne Show
By: Alicia
reinvs
i hated the rain
at least my handphone did not kenna tio
after i took my umbrella out ,i became a instant celebrity
hmmm....
i suggest they should serve bags with better straps not straps breaking all over the places.
and provide longer ponchos ......
The fun and horrible NE show!!!
Done by:Low Qiu En
my horrific NE experience BY: gareth
national day
by shirleen
Ne show by Celine
When I reached my school,I put down my bag and waited at the hall.Soon,many people came in and sat down.Then we went up the school-bus .After about an hour,we reached there.It was beautiful scenery,there were a lot of trees there.It was a big place.
The weather was cloudy.It then started. I took a lot of pictures and videos.Soon when it was going to finsh,It rained heavily.We went home wet but happy.
My N.E show experience!!! From Xin yi
NE Show!
By:JieYi
The NE show
The NE Show!!!
1) Took photos of Pei Zhen (Secretly, that is.... u'll come to know y SECRETLY.... in time to come...) Dun get angry with me when u c this, ok Pei Zhen?????
2) Ate snacks
Tell u more later... Bye! By: Calvin
my ne show experience
by
Min Zhe
The NE Show
My NE Day Experience
When we reached there, we proceeded to our seats and sat down to wait for the show to start. Two of the Mediacorp artistes were there hosting the show. The show was very exciting and nice. Before the show, there were some light drizzles and a rainbow appeared but when it was about 8.30pm, it started to rain very heavily.
When I was about to go down the stairs, water was flowing down continously which made the staircase look like a waterfall. When I got home, it was already 11pm. It was a fun but tiring day for me.
NDP show
NDP show
The NDP show was fun,funny and was a disater!The video clip was so funny about the army when there was a bomb in Singapore.Mark lee , michelle , and 2 more people were there too!At the Marina Bay it had been raining for a lot of times!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!As the show was about to end suddenly a heavy downpir came it was raining so heavily,nut the rain was cooling.When we were on the bus it was so COLD it seem that it was FREEZING!It was so fun at marina bay!
About NE show
How do dolphins sleep?
NE Show
~*Evelyn*
NE show
BY:Raqib
NPD SHOW
My NE show experience
Does dolphins sleep??
Dolphins, like humans, are mammals. They are warm-blooded, bear live young, breathe air, and they require sleep. However, for dolphins, sleeping and breathing at the same time can pose a bit of a problem. Humans are able to breathe during sleep as they live on land and can perform the task unconsciously. However, dolphins are aquatic mammals; they must actively make the decision to breathe and come up to the surface for air. Fortunately, as Bob Holmes notes in his May 1, 2009 article "'Brain-juggling' lets dolphins avoid sleep deprivation" published in NewScientist, nature has come up with a remarkable solution to the problem so that dolphins sleep without drowning.
How Do Dolphins Sleep?
The February 2, 1998 Scientific American article "How do whales and dolphins sleep without drowning" describes this interesting process of dolphin sleeping. Dolphins are able to send one half of their brain to sleep at a time so that they are never completely unconscious.The other half of the brain monitors what’s going on, ensuring that the animal stays out of danger and continues to breathe. Which half sleeps switches from nap to nap. Dolphins often swim with dolphins in groups called pods. During sleep they keep at least one eye open, allowing them to stay in contact with the others in the pod and coordinate their movements. Although they could likely sleep anywhere, usually dolphins sleep near the surface so that they can come up for air easily. These creatures can often be seen swimming slowly near the surface with little movement. This action is called “logging” and these dolphins are at rest.
Do Dolphins Have Dreams?
Perhaps dolphins dream about their day, eating, chatting with other dolphins, a round-the-world swim with dolphins in pods. The truth is nobody knows for sure. However, Margaret Klinowska does note in her September 26, 1994 essay “Brains, Behaviour and Intelligence in Cetaceans” published in the second edition of 11 Essays on Whales and Man, that dolphins are one of the few mammals that do not have REM sleep. Humans sleep during the REM stage of the sleep cycle. One could deduce that if dolphins don’t have a REM stage, then they can’t have dreams. However, some scientists dispute this claim and say dolphins merely have very low levels of REM sleep. It’s also possible that dolphins sleep and dream differently from humans. Studies done on captive belugas and grey whales show that these aquatic mammals sometimes have muscular spasms during their brief REM stage, which could be associated with dreaming.
How Do Scientists Know Dolphins Sleep?
Scientists don’t just swim with dolphins and watch them for hours, although observation is an important component of their studies. The 1998 Scientific American article describes how scientists use electroencephalography – hooking up electrodes to captive dolphins’ heads and measuring the electricity levels in their brains. The resulting data is an electroencephalogram or EEG. The EEG shows that during sleep, half of the dolphin’s brain is active while the other half shuts down. Studies show that dolphins sleep about eight hours a day.
by WEIJIE .
The NE Show!!!
NE show
NDP SHOW
The NDP show rehearsal!!!
NE show on 11th July 09 (done by Zilin)
Sunday, 12 July 2009
Why do plants need nitrogen?
By: Alicia
Why plants need Nitrogen
~Evelyn
The food and water-carrying tubes
plants need nitrogen?
The water and food carrying tubes
Why plants need nitrogen???
Why plants need nitrogen?
Answer:All plants need nitrogen to make amino acids, proteins and DNA, but the nitrogen in the atmosphere is not in a form that they can use. Other plants get the nitrogen they need from the soils or water in which they live mostly in the form of inorganic nitrate (NO3-). Nitrogen is a limiting factor for plant growth.
Friday, 10 July 2009
Food carrying tubes and Water carrying tubes
Water carrying tube is Xylem.
food and water carrying tubes
Why plants need nitrogen?
Why plants need nitrogen?
food and water carring tubes in plants
the tube that carry food is called the phleom!
j.x
why do plants need nitrogen?
n.j.x
Why do plants need nitrogen?
reinvs nitro
This illustration shows the general pathways of nitrogen through the biological and physical components of the Earth system. Click on image for full size (190 Kb)NCAR
Nitrogen is an element that is found in both the living portion of our planet and the inorganic parts of the Earth system. The nitrogen cycle is one of the biogeochemical cycles and is very important for ecosystems. Nitrogen moves slowly through the cycle and is stored in reservoirs such as the atmosphere, living organisms, soils, and oceans along its way.
Most of the nitrogen on Earth is in the atmosphere. Approximately 80% of the molecules in Earth's atmosphere are made of two nitrogen atoms bonded together (N2). All plants and animals need nitrogen to make amino acids, proteins and DNA, but the nitrogen in the atmosphere is not in a form that they can use. The molecules of nitrogen in the atmosphere can become usable for living things when they are broken apart during lightning strikes or fires, by certain types of bacteria, or by bacteria associated with legume plants. Other plants get the nitrogen they need from the soils or water in which they live mostly in the form of inorganic nitrate (NO3-). Nitrogen is a limiting factor for plant growth. Animals get the nitrogen they need by consuming plants or other animals that contain organic molecules composed partially of nitrogen. When organisms die, their bodies decompose bringing the nitrogen into soil on land or into the oceans. As dead plants and animals decompose, nitrogen is converted into inorganic forms such as ammonium salts (NH4+ ) by a process called mineralization. The ammonium salts are absorbed onto clay in the soil and then chemically altered by bacteria into nitrite (NO2-) and then nitrate (NO3- ). Nitrate is the form commonly used by plants. It is easily dissolved in water and leached from the soil system. Dissolved nitrate can be returned to the atmosphere by certain bacteria in a process called denitrification.
Certain actions of humans are causing changes to the nitrogen cycle and the amount of nitrogen that is stored in reservoirs. The use of nitrogen-rich fertilizers can cause nutrient loading in nearby waterways as nitrates from the fertilizer wash into streams and ponds. The increased nitrate levels cause plants to grow rapidly until they use up the nitrate supply and die. The number of herbivores will increase when the plant supply increases and then the herbivores are left without a food source when the plants die. In this way, changes in nutrient supply will affect the entire food chain. Additionally, humans are altering the nitrogen cycle by burning fossil fuels and forests, which releases various solid forms of nitrogen. Farming also affects the nitrogen cycle. The waste associated with livestock farming releases a large amount of nitrogen into soil and water. In the same way, sewage waste adds nitrogen to soils and water
why do plants need nitrogen? By: Gareth
Why do plants need nitrogen?
All plants need nitrogen to make amino acids, proteins and DNA, but the nitrogen in the atmosphere is not in a form that they can use. Other plants get the nitrogen they need from the soils or water in which they live mostly in the form of inorganic nitrate (NO3-). Nitrogen is a limiting factor for plant growth.
Why do plants need nitrogen and magnesium?
Nitrogen is an important component of many important structural, genetic and metabolic compounds in plant cells. it is a major component of chlorophyll, the compound by which plants use sunlight energy to produce sugars from water and carbon dioxide. it is also major component of amino acids, the building blocks of proteins. Nitrogen is a component of energy-transfer compounds, such as ATP which allows cells to conserve and use the energy released in metabolism. nitrogen is a significant component of nucleic acids such as, DNA, the genetic material that allows reproduction. Phosphorus is an essential nutrient both as a part of several key plant structure compounds and as a catalysis in the conversion of numerous key biochemical reactions in plants. Phosphorus is noted especially for its role in capturing and converting the sun’s energy into useful plant compounds. The two examples that follow illustrate how vital phosphorus nutrition is to normal plant development and production. Phosphorus is a vital component of DNA, the genetic "memory unit" of all living things. Itis also a component of RNA, the compound that reads the DNA genetic code to build proteins and other compounds essential for plant structure, seed yield, and genetic transfer. The structures of both DNA and RNA are linked together by phosphorus-bonds.Phosphorus is a vital component of ATP, the "energy unit" of plants. ATP forms during photosynthesis, has phosphorus in its structure, and processes from the beginning of seedling growth through to the formation of grain and maturity. Thus, phosphorus is essential for the general health and vigor of all plants.Some specific growth factors that have been associated with phosphorus are: stimulated root development, increased stalk and stem strength, improved flower formation and seed production, more uniform and earlier crop maturity, increased nitrogen N-fixing capacity of legumes, improvements in crop quality, and increased resistance to plant diseases.
Dictionary:
Phosphorus: A highly reactive, poisonous, non-metallic element occurring naturally in phosphates, especially apatite, and existing in three allotropic forms, white (or sometimes yellow), red, and black. An essential constituent of protoplasm, it is used in safety matches, pyrotechnics, incendiary shells, and fertilizers and to protect metal surfaces from corrosion. Atomic number 15; atomic weight 30.9738; melting point (white) 44.1°C; boiling point 280°C; specific gravity (white) 1.82; valence 3, 5.
RNA: Short for ribonucleic acid. The nucleic acid that is used in key metabolic processes for all steps of protein synthesis in all living cells and carries the genetic information of many viruses. Unlike double-stranded DNA, RNA consists of a single strand of nucleotides, and it occurs in a variety of lengths and shapes. RNA also differs from DNA in having the pyrimidine base uracil instead of thymine and in having ribose instead of deoxyribose in its sugar-phosphate backbone. In eukaryotes, RNA is produced in the cell nucleus. Messenger RNA is RNA that carries genetic information from the cell nucleus to the structures in the cytoplasm (known as ribosomes) where protein synthesis takes place. Ribosomal RNA is the main structural component of the ribosome. Transfer RNA is RNA that delivers the amino acids necessary for protein synthesis to the ribosomes.