Sekali skla jengok & stadi balik psl fisioterapi ni best jgk...ngeee,lama dah tingglkan sume citer bab2 biologi,kmia nih. Klu la aku stdi btl2 tme SPM dlu,mybe skg aku dah xlma lg jd grduate in medic...heheh,pa ble bt. Bukn rzki aku dlm bidg ni So,dikesempatan nih bgs gk lyn ttg body structre.Copy dr intrnet ja....
The basic body structure consists of two body parts. They are the cephalothorax and the abdomen.
CEPHALOTHORAX
The cephalothorax consists of the external body parts. In short, it is basically the head of the spider.
It has a face that consists of a tiny mouth with no teeth.
It has fangs, or chelicerae, that is used to seize prey. They resemble a hollow claw that if looked at with a microscope, will show that they point in a downward position. Located at the base of these fangs are the poison glands. When the spider is pursuing the victim, it will pierce it with the fangs. Venom, which varies with different spiders, is injected. The venom will only paralyze the victim because a spider will not eat dead prey. Since the spider cannot actually chew, a digestive juice is injected. This breaks down the nutrients of the victim so that the spider may feed. It is kind of like sucking through a straw. This process is known as suctorial feeding.
Another feature on the head are a pair of pedipalp. "The pedipalps are either the second pair of appendages of spiders, and other arachnids, variously developed for grasping, sensing, fertilizing, etc." as defined by Webster's New World Dictionary4. Basically, if you look really close, these pedipalp look like a tiny pair of legs that have six segments (our fingers only have three). The segments closest to the head are used for crushing food.
What would a face be without those beautiful eyes?! We have two. A common number for a spider is eight, placed on their face in two rows of four. Depending on the spider, six, four, two, or zero (in the case of a cave spider this is literally blind.) Spiders' eyes are simple. This means that they are not divided into pieces like a compound eye. Some spiders that live in dark places or hunt at night have nocturnal eyes. These eyes are whitish in color and have a pearly luster. The rest of the spiders have diurnal eyes. These eyes vary in color.These previous sections make up their face.
The last major component of the cephalothorax, and one of the intimidating components to some is the legs. ALL spiders have eight legs. Each leg has seven segments. Most spiders have a tiny claw at the end of each leg and a little pad of hair around this claw to assist the spider in climbing.
ABDOMEN
The abdomen is the larger of the two body parts. It consists of all the internal body parts of the spider.
The nervous system has a brain acts as the control system for all the other parts of the spider. A spider does not "think" like a mammal does. Instead, it gains its knowledge of its surroundings by sense organs. Each hair on the spiders body contains a nerve. When touched, these nerves tell the spider how to respond.7
The circulatory system transfers blood throughout the spiders' body. Spiders have transparent blood. The circulatory systems includes a long, slender heart. If the spiders' body is broken or punctured, its blood will drain and the spider will die.
There are muscles in a spiders' body but the blood is necessary for the legs to extend. Low blood pressure would make the spider's legs curl up and make it unable to walk.
The digestive extends through the length of the body. The stomach pulls the food, or nutrient broth, through special digestive juices. The food is then distributed though the blood. Because of this unique process, there is no need for an excretory system.
At the base of the abdomen, there are fingerlike spinnerets. Most spiders have six, but some have four or two. At the tip of the spinnerets closest to the body, there is a spinning field. It is covered by as many as one hundred spinning tubes. Silk flows through these tubes from a silk gland inside.
We have a nose, spiders have a spiracle. It is located on the tip of the rear of the abdomen. It is located just in front of the spinneretts. A spider has two breathing organs, trachae and booklungs. Almost all trachae tubes carry air throughout the body. The air enters tubes through the spiracle. The book lungs consist of 15 or more folds. The air enters here and is passed through to go to the blood
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