Download - Sc Form 2 Chapter 1
SCIENCE FORM 2CHAPTER 1
THE WORLD THOUGH OUR SENSES
DUNIA MELALUI DERIA KITA
SENSORY ORGANS/ ORGAN-ORGAN DERIA
A stimulus is a change in the enviroment that produces a reaction in living thing/ Ransangan adalah suatu perubahan dalam persekitaran yang menghasilkan gerak balas kepada sesuatu organisma
Sense is the ability of the sensory organ to detect a stimulus/ Deria ialah kebolehan organ deria utk mengesan ransangan(perubahan)
The sensory organ enable a organism to detect changes that occur in enviroment/ Organ deria membolehkan organisma mengesan perubahan yang berlaku di sekelilingnya
All the information from the sensory organ will carry out to the brain to process the information through the nerve system/ Semua maklumat yg dikesan oleh deria akan dibawa ke otak utk diproses melalui sistem saraf
Respons is a reaction produced by stimulus/ Gerak balas ialah tindakan hasil drpd ransangan
Stimulus Sensory organ Nerves Brain Nerves Respons
SENSORY ORGANS/ ORGAN-ORGAN DERIA
SENSORY ORGANS /ORGAN-ORGAN DERIA
Tongue/ Lidah
Skin/ Kulit
Eye/ Mata
Nose/ Hidung
Ear/ Telinga
SENSE OF TOUCH/ DERIA SENTUHAN
Sensory organ response to pain, touch, pressure, heat and cold/ Deria kulit bertindak terhadap kesakitan, sentuhan, tekanan, kepanasan dan kesejukan
Skin also has 5 types of receptorsa) Pain receptor d) Cold receptorb) Touch receptor e) Pressure receptorc) Heat receptor
Sensitivity of skin depends on/ Kepekaan deria sentuhan bergantung kpda) Thickness of skin/ Ketebalan kulitb) Number of sensory nerves/ Jumlah saraf deria
SENSE OF TOUCH/ DERIA SENTUHAN
SENSE OF SMELL/ DERIA BAU
Nose is sensory organ for smell/ HidungOrgan deria bau
Sensory receptor sensitive to chemical in air/ Reseptor deria sensitif kpd bahan kimia dlm udara
The sensory receptor is located at the upper nasal cavity and cover with mucus/ Reseptor deria terletak di rongga atas hidung dan diliputi oleh mukus
When the chemical vapour dissolves, it stimulate and create information to the brain and the brain will identify the smell/ Apabila bahan kimia larut di dalam mukus, ia akan diransang dan menghantar maklumat ke otak dan otak akan menngenalpasti bau tersebut
SENSE OF SMELL/ DERIA BAU
SENSE OF TASTE/ DERIA RASA
Sensory organ for taste is tongue/ Lidah ialah organ deria rasa
Tongue is cover by taste buds which contains many taste receptor/ Lidah diliputi oleh tunas rasa yg mengandungi byk reseptor rasa
TasteTaste
SweetSweet SaltySalty SourSour BitterBitter
BitterBlack coffee
SourLime,
Vinegar
SaltySea water,
salt
SweetHoney, sugar
SENSE OF TASTE/ DERIA RASA
Taste receptor can only detect chemicals in food which dissolved in saliva/ Reseptor rasa boleh mengesan bhn kimia di dlm makanan yg terlarut di dalam air liur
Both of smell and taste are needed to detect flavour of food/ Kedua-dua deria bau dan rasa diperlukan utk mengesan rasa makanan
SENSE OF TASTE/ DERIA RASA
SENSE OF HEARING/ DERIA PENDENGARAN
Ear is sensory organ which detect sound/ Telinga adalah organ yg mengesan bunyi
The eustachian tube and the semicircular canals are NOT involved in the hearing mechanism/ Tiub eustachio dan salur separa bulat TIDAK terlibat dengan bunyi
SOUND PATHWAY/ LALUAN BUNYI
1 2
3
4
56
7
1. Pinna2. Auditory
Canal3.
Eardrum4. Ossicles
5. Oval window
6. Cochlea7. Auditory
nerve8. Brain
THE FUNCTION OF DIFFERENT EAR PARTS/ FUNGSI BAHAGIAN TELINGA
Functions
Pinna - Collect sound waves
- Direct them into auditory canal
Auditory canal - Sends the sound waves to the eardrum
Eardrum - Vibrates the same frequency as the sound
waves
Ossicles - Magnifies the vibration
- Transfer the vibrations from eardrum to oval
window
Cochlea - Detects vibrations
- Converts vibration to nerve impulses
SENSE OF SIGHT/ RANGSANGAN PENGLIHATAN
SENSE OF SIGHT/ DERIA PENGLIHATAN
Eye is a sense organ that detect light/ Mata ialah organ yang mengesan cahaya
Made up of three layers/ Terdiri daripada 3 lapisan
a) Sclera – outher layer/ sklera – lapisan luar
b) Choroid – middle layer/ koroid – lapisan tengah
c) retina – innermost layer/ retina – lapisan paling dalam
Parts of eyes that help focus the light onto retina/ Bahagian mata yang menolong memfokuskan cahaya ke dalam retina ialah a) Cornea/ Kornea b) aqueous humour/ gelemairc) lens/ kanta d) vitreous humour/ gelemaca
Eye able to focus light by changing the thickness of the lens/ Mata boleh memfokus cahaya dgn menukar ketebalan kanta
SENSE OF SIGHT/ DERIA PENGLIHATAN
The light path in the human eye is shown below
CorneaCornea Aqueous humourAqueous humour PupilPupil
LensLensVitreous humourVitreous humourRetinaRetina
Optic Optic nervenerve
FUNCTION OF THE DIFFERENT PART OF EYES/ FUNGSI BAHAGIAN MATA
Structure/ Struktur
Functions/ Fungsi
Sclera - Protect the eyes
Choroid - Support food and oxygen to the eyes- Absorb light and prevent reflection of light
Retina - Detect light- Produces nerves impuls
Yellow spot - Detect images of formed on it
Cornea - Helps to focus light on retina
Iris -Controls the size of the pupil-Controls the amount of light entering the eye
Pupil -Allow light to enter the eye
Structure/ Struktur Functions/ Fungsi
Lens - Focuses light on the retina
Suspensory ligaments - Holds the lens in place
Ciliary body - Changes the thickness of the lens
Aqueous humour - Helps to focus light on retina
Vitreous humour - Helps to keep the eye ball firm
Optic nerve - Sends nerve impuls from the retina to the brain
FUNCTION OF THE DIFFERENT PART OF EYES/ FUNGSI BAHAGIAN MATA
LIGHT AND SIGHT/ CAHAYA DAN PENGLIHATAN
1. Reflection and Refraction/ Pantulan &
Pembiasan
- Light can be reflected and refracted
- Reflection is bouncing of light off an object or surface/ Pantulan ialah pembalikan cahaya daripada objek atau permukaan
- We can see because the object reflects light into our eyes/ Kita boleh melihat sesuatu objek krn cahaya telah dipantulkan ke dalam mata kita
- - For examples,a) Dentist use the mirror to see the teethb) Contexs mirror at the bend road for safetyc) Vehicle rear-view
- Refraction is the bending of light as it passes from one transparent medium to another/ Pembiasan ialah pembengkokan cahaya apabila ianya melalui bahan lutsinar yang berbeza ketumpatan
As example, Pencil in this picture looks like bending in water. It’s actually not bending, but the light will reflection as it pass though the water which has different density.
It is bending or not?
Actually fish located
Fish located in our eyes
Defects of vision and ways to correct them/Kecacatan pada penglihatan dan caraMembetulkannya
The common defects of vision is/Kecacatan mata yang biasa ditemui ialaha) Long sightedness/ Rabun jauhb) Short sightedness/ Rabun dekatc) Astigmatism/ Astigmatisme
SHORT SIGHTEDNESS/ RABUN DEKAT Can see NEAR objects/
Boleh melihat objek dekat
FAR object appear blurredObjek yg jauh kabur
Image formed in FRONT of the retinaImej terbentuk di hadapan retina
IMEJ DI HADAPAN RETINA
Cause:-Eye ball is too big/long
Bebola mata terlalu besar/ panjang
Lens is too thickKanta mata yg TEBAL
Correction:- Use suitable concave lens
Gunakan kanta cekung
LONG SIGHTEDNESS/ RABUN JAUH
Can see FAR objects/Boleh melihat objek JAUH
NEAR object appear blurredObjek yg DEKAT kabur
Image formed in BEHINDof the retinaImej terbentuk di BELAKANG retina
IMEJ DI BELAKANG RETINA
Cause:- Eye ball is too SMALL/SHORT
Bebola mata terlalu KECIL/ PENDEK Lens is too THIN
Kanta mata yg nipis
Correction:- Use suitable CONVEX lens
Gunakan kanta CEMBUNG
LIMITATION OF SIGHT
Some common examples of the limitation of sight are
a) Blind spot b) Optical illusion c) Monocular and stereoscopic visions
DEVICES TO OVERCOME THE LIMITATION OF SIGHT
DEVICES TO OVERCOME THE LIMITATION OF SIGHT/ Alat untuk mengatasi had penglihatan
Device Function
Microscope To examine a very tiny organisms/ utk memeriksa organisma yg terlalu kecil
Magnifying glass
To magnify the image of small object/ utk membesarkan objek yg kecil
Telescope Enables us to see a far object/ membolehkan kita melihat objek yg jauh
Binoculars Enables to see far away object/ membolehkan melihat objek yg jauh
Ultrasound scanning
Enables to see the fetus of pregnant mother/ melihat janin pd ibu mengandung