parasitism ( sains form 2)

7/26/2019 parasitism ( sains form 2)

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SCIENCE; CH A P TERP A R A SI T



EXPLANATION OF PARASITISM;







O ther examples are (a) s tem borers and oil palm

lea ves

(b) tree barnacles and trees

(c) aphids and mus tard plan ts




•USUALLY, ALTHOUGH PARASITES HARM THEIR HOST

IN THE PARASITE'S BEST INTEREST NOT TO KILL THE

BECAUSE IT RELIES ON THE HOST'S BODY AND BODY

FUNCTIONS, SUCH AS DIGESTION OR BLOOD

CIRCULATION, TO LIVE.



EXPLANATION OF PARASITISM;• SOME PARASITIC ANIMALS ATTACK PLANTS. APHIDS ARE INSECTS THAT EAT THE SAP FROM T

ON WHICH THEY LIVE.

• PARASITIC PLANTS AND FUNGI CAN ATTACK ANIMALS. A FUNGUS CAUSES LUMPY JAW, A DISE

INJURES THE JAWS OF CATTLE AND HOGS.

• THERE ARE ALSO PARASITIC PLANTS AND FUNGI THAT ATTACK OTHER PLANTS AND FUNGI. A P

FUNGUS CAUSES WHEAT RUST AND THE DOWNY MILDEW FUNGUS ATTACKS FRUIT AND VEGE




• SOME SCIENTISTS SAY THAT ONECELLED BACTERIA AND VIRUSES THAT LIVE IN ANIMALS AN

THEM, SUCH AS THOSE THAT CAUSE THE COMMON COLD, ARE PARASITES AS WELL.

• HOWEVER, THEY ARE STILL CONSIDERED DIFFERENT FROM OTHER PARASITES. MANY TYPES O

PARASITES CARRY AND TRANSMIT DISEASE. LYME DISEASE IS TRANSMITTED BY DEER TICKS

• A PARASITE AND ITS HOST EVOLVE TOGETHER. THE PARASITE ADAPTS TO ITS ENVIRONMENT

AND USING THE HOST IN WAYS THAT HARM IT.




•HOSTS ALSO DEVELOP WAYS OF GETTING RID OF OR PROTECTING

THEMSELVES FROM PARASITES. FOR EXAMPLE, THEY CAN SCRATCH

TICKS. SOME HOSTS ALSO BUILD A SYMBIOTIC RELATIONSHIP WIT

ANOTHER ORGANISM THAT HELPS TO GET RID OF THE PARASITE.

•LADYBUGS LIVE ON PLANTS, EATING THE APHIDS AND BENEFITING

GETTING FOOD, WHILE THE PLANT BENEFITS BY BEING RID OF THE A

http://www.necsi.edu/projects/evolution/co-evolution/symbiosis/co-evolution_symbiosis.html

http://www.necsi.edu/projects/evolution/co-evolution/symbiosis/co-evolution_symbiosis.html

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parasitism ( sains form 2)