Take a closer look at these eyes and see which one that match your eyes!
Tuesday, June 9, 2009
Eye Chart ..... see which one is your eye?
Take a closer look at these eyes and see which one that match your eyes!
Friday, June 5, 2009
Your beautiful EYES .... blue, brown, black or green?
Eyes are organs that detect light, and send signals along the optic nerve to the visual and other areas of the brain. Complex optical systems with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in cnidaria, molluscs, chordates, annelids and arthropod
s. The simplest "eyes", such as those in unicelluler organisms, do nothing but detect whether the surroundings are light or dark, which is sufficient for the entrainment of circadian rhythms. From more complex eyes, retinal photosensitive ganglion cells send signals along the retinophypothalamaic tract to the suprachiasmatic nuclei to effect circadian adjustmenRelationship to lifestyle
Eyes are generally adapted to the environment and lifestyle of the organism which bears them. For instance, the distribution of photoreceptors tends to match the area in which the highest acuity is required, with horizon-scanning organisms, such as those that live on the African plains, having a horizontal line of high-density ganglia, while tree-dwelling creatures which require good all-round vision tend to have a symmetrical distribution of ganglia, with acuity decreasing outwards from the centre.
Of course, for most eye types, it is impossible to diverge from a spherical form, so only the density of optical receptors can be altered. In organisms with compound eyes, it is the number of ommatidia rather than ganglia that reflects the region of highest data acquisition. Optical superposition eyes are constrained to a spherical shape, but other forms of compound eyes may deform to a shape where more ommatidia are aligned to, say, the horizon, without altering the size or density of individual ommatidia. Eyes of horizon-scanning organisms have stalks so they can be easily aligned to the horizon when this is inclined, for example if the animal is on a slope. An extension of this concept is that the eyes of predators typically have a zone of very acute vision at their centre, to assist in the identification of prey. In deep water organisms, it may not be the centre of the eye that is enlarged. The hyperiid amphipods are deep water animals that feed on organisms above them. Their eyes are almost divided into two, with the upper region thought to be involved in detecting the silhouettes of potential prey — or predators — against the faint light of the sky above. Accordingly, deeper water hyperiids, where the light against which the silhouettes must be compared is dimmer, have larger "upper-eyes", and may lose the lower portion of their eyes altogether. Depth perception can be enhanced by having eyes which are enlarged in one direction; distorting the eye slightly allows the distance to the object to be estimated with a high degree of accuracy.
Acuity is higher among male organisms that mate in mid-air, as they need to be able to spot and assess potential mates against a very large backdrop. On the other hand, the eyes of organisms which operate in low light levels, such as around dawn and dusk or in deep water, tend to be larger to increase the amount of light that can be captured.
It is not only the shape of the eye that may be affected by lifestyle. Eyes can be the most visible parts of organisms, and this can act as a pressure on organisms to have more transparent eyes at the cost of function.
Eyes may be mounted on stalks to provide better all-round vision, by lifting them above an organism's carapace; this also allows them to track predators or prey without moving the head.
Nose ..... how sensitive can it be?
Anatomically, a 
nose
is a protuberance in vertebrates that houses the nostrils, or nares, which admit and expel air for respiration in conjunction with the mouth. Behind the nose is the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passes through the pharynx, shared with the digestive system, and then into the rest of the respiratory system. In humans, the nose is located centrally on the face; on most other mammals, it is on the upper tip of the snout.In cetaceans, the nose has been reduced to the nostrils, which have migrated to the top of the head, producing a more streamlined body shape and the ability to breathe while mostly submerged. Conversely, the elephant's nose has elaborated into a long, muscular, manipulative organ called the trunk.
Air conditioning
As an interface between the body and the external world, the nose and associated structures frequently perform additional functions concerned with conditioning entering air (for instance, by warming and/or humidifying it, also for flicking if moving and by mostly reclaiming moisture from the air before it is exhaled (as occurs most efficiently in camels). The nose hairs are able to stop unwanted particles from entering the lungs.
Smelling
In most mammals, the nose is the primary large organ for smelling. As the animal sniffs, the air flows through the nose and over structures called turbinates in the nasal cavity. Turbulent flow will promote mixing of the air in the nasal cavity allowing the molecules of a newly inhaled breath of air to reach the sensitive epithelium as fast as possible. Laminar flow would imply a stationary layer of air around the epithelium only to be entered by diffusion. Sniffing will cause more turbulence also. At the olfactory epithelium, odor molecules carried by the air dissolve in the fluid covered cilia of the olfactory receptor neurons, where they bind to specific receptor proteins causing a depolarization of the receptor cell. At the glomeruli dendrites of many receptor cells sensitive to the same kind of odor converge and from there a signal is forwarded to the brains olfactory region.
Sense of direction
The wet nose of dogs is useful for the perception of direction. The sensitive cold receptors in the skin detect the place where the nose is cooled the most and this is the direction a particular smell that the animal just picked up comes from.
Thursday, June 4, 2009
Wednesday, June 3, 2009
Tuesday, June 2, 2009
Monday, June 1, 2009
Choose the shape of your face, here!
a. Long
b. Square
c. Round
d. Oval
e. Pear
f. Diamond
The face forms a part of the human body: the front of the head.
The term face refers to the central sense organ complex, for those animals that have one, normally on the ventral surface of the head and can depending on the definition in the human case, include the hair, forehead, eyebrow, eyes, nose, ears, cheeks, mouth, lips, philtrum, teeth, skin, and chin. The face has uses of expression, appearance, and identity amongst others. It also has different senses like smelling, tasting, hearing, and seeing.
Plastic surgery
Cosmetic Surgery can be used to alter the appearance of the facial features. Plastic surgery ( is a medical specialty concerned with the correction or restoration of form and function. While famous for aesthetic surgery, plastic surgery also includes two main fields: cosmetics and reconstructive surgery. The word "plastic" derives from the Greek plastikos meaning to mold or to shape; its use here is not connected with the synthetic polymer material known as "palstic") may also be used in cases of facial trauma, injury to the face. Severely disfigured individuals have recently received full face transplants.
Anatomy of the Face Underlying Facial ExpressionThe anatomy of the face is significant for understanding the behaviors, functions, and appearances of the face.
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