Wei+Heng

Wei Heng Tan's Page __**Classification**__

 * Kingdom- Killing**


 * Phylum - People**


 * Class - Causes**


 * Order - Other**


 * Family - Family**


 * Genus - Gainig**


 * Species - Spices**


 * White Tiger**
 * What are the different CLASSES of vertebrates?**
 * 1) **Fish**
 * 2) **Reptiles**
 * 3) **Mammals**
 * 4) **Birds**
 * 5) **Amphibians**


 * What are some characterisitcs of each?**
 * 1) **Fish -A fish has scales,fins,breathes through its gills,swims,lives under water and lays eggs.**
 * 2) **Reptiles - They are ectothermic, they have 3 chambered hearts (not crocs though), they have scales, they have claws and they lay eggs.**
 * 3) **Mammals - they breathe aire,give birth to live young,mammary glands, 3 middle ear bones and they have hair.**
 * 4) **Birds-They have 4 chambered hearts, Their skin is covered with feathers, their bones are light weight, They lay eggs and Their forelimbs are modified as wings**
 * 5.Amphibians -They have smooth skin, dependent on moisture, they have 3 chamber hearts like the reptiles, they lack claws or toes and lay eggs.**


 * Solid- Solid is a fixed structure with strong sides and bonds. The feeling when you touch it is hard and strong.**


 * Liquid- Liquid is a weak structure which moves around to fit the container it is in. The feeling when you it is wet and weak.**

Student task four
 * Gas- Gas is a no bond substanstance that floats around its container. The feeling of gas depends on what type it is. Example if it was hot it would fell hot or warm.**
 * Colliods**
 * Foam-**
 * Foam is the mixture of gas and liquid. There for when mixed together you get the colliod foam**
 * We use the colloid foam in our every day lives sometimes not noticing it is to different types of matter put together ( gas and liquid).**
 * Some forms of foam we use every day are things such as:**
 * -Shaving cream**
 * Can you trust your senses?**
 * 1. Where does the most bending of the light occur in the eye?**
 * Answear: The Lens**
 * 2. Describe how the lens works**
 * Answear: It focous the light to the Cones and Rods**
 * 3. Why do we squint when exposed to bright light?**
 * We squint because there is to much light coming into our eye for the pupil to take**
 * ( I think this is because the pupil can not get any smaller so we squint to stop to much light coming in).**
 * 4. Which parts of the eye are involved in focusing?**
 * The parts of your eyes that are involed in focusing are lens, cornea and iris.**
 * 5. Discuss the implications of losing one eye?**
 * -Losing an eye effects you alot. Firstly it would be harder to see things without a joint perspective of two eyes and secondly it would also**
 * effect you when you wanted to play a sport such as tennis because it would be harder to know where the ball is and not hit close enough.**

Research an animal that has unsual senses. Include a picture Describe which sense are developed in a special way How do they work - how does the animal use them? Are any of the animal's senses UNDERDEVELOPED? Why do you think this is? Present all this on your student page.

= DOGS =


 * Scenes that are developed in a special way: Sight,Hear,Smell**
 * Sight:**
 * The dog's visual system has evolved to aid proficient hunting. While a dog's visual acuity is poor (that of a poodle's has been estimated to translate to a Snellen rating of 20/75), their visual discrimination for moving objects is very high; dogs have been shown to be able to discriminate between humans (e.g. identifying their owner) from distances up to a mile. As crepuscular hunters, dogs often rely on their vision in low light situations: they have very large pupils, a high density of rods in the fovea, an increased flicker rate, and a tapetum lucidum. The tapetum is a reflective surface behind the retina that reflects light back to give the photoreceptors a second chance to catch the photons.**


 * The eyes of different breeds of dogs have different shapes, dimensions, and retina configurations. Many long-nosed breeds have a "visual streak" – a wide foveal region that runs across the width of the retina and gives them a very wide field of excellent vision. Some long-muzzled breeds, particularly the sighthounds, have a field of vision up to 270° (compared to 180° for humans). Short-nosed breeds, on the other hand, have an "area centralis": a central patch with up to three times the density of nerve endings as the visual streak, giving them detailed sight much more like a human's. Some broad-headed breeds with short noses have a field of vision similar to that of humans. Most breeds have good vision, but some show a genetic predisposition for myopia – such as Rottweilers, where one out of every two has been found to be myopic.**


 * Hear:**
 * The frequency range of dog hearing is approximately 40 Hz to 60,000 Hz, which means that dogs can detect sounds far beyond the upper limit of the human auditory spectrum. Additionally, dogs have ear mobility which allows them to rapidly pinpoint the exact location of a sound. Eighteen or more muscles can tilt, rotate, raise, or lower a dog's ear. A dog can identify a sound's location much faster than a human can, as well as hear sounds at four times the distance.**

= Rabbits =
 * Smell:**
 * While the human brain is dominated by a large visual cortex, the dog brain is dominated by an olfactory cortex. The olfactory bulb in dogs is roughly forty times bigger than the olfactory bulb in humans, relative to total brain size, with 125 to 220 million smell-sensitive receptors. The bloodhound exceeds this standard with nearly 300 million receptors. Dogs can discriminate odors at concentrations nearly 100 million times lower than humans can. The wet nose is essential for determining the direction of the air current containing the smell. Cold receptors in the skin are sensitive to the cooling of the skin by evaporation of the moisture by air currents.**


 * Scenes that are developed in a special way: Taste**


 * Taste:**
 * Tongue contains 17,000 taste buds. **