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www.GOALias.blogspot.com1.4 S1.4 SAPROTROPHSYou might have seen packets ofmushrooms sold in the vegetablemarket. You may have also seen fluffyumbrella-like patches growing on rottingwood during the rainy season (Fig. 1.7).Let us find out what type of nutrientsthey need to survive and from wherethey get them.Fig. 1.7 Packet of mushrooms, a mushroomgrowing on decayed materialBoojho wants to know howthese organisms acquirenutrients. They do not havemouths like animals do. They arenot like green plants as they lackchlorophyll and cannot make foodby photosynthesis.Fig. 1.8 Fungigrowing on breadWrite down your observations in yournotebook. Most probably you will seecotton-like threads spread on the pieceof bread.These organisms are called fungi.They have a different mode of nutrition.They secrete digestive juices on the deadand decaying matter and convert it intoa solution. Then they absorb thenutrients from it. This mode of nutritionin which organisms take in nutrients insolution form from dead and decayingmatter is called saprotrophic nutrition.Plants which use saprotrophic mode ofnutrition are called saprotrophs.Fungi also grow on pickles, leather,clothes and other articles that are leftin hot and humid weather for long time.Activity 1.2Take a piece of bread and moisten it withwater. Leave it in a moist warm placefor 2–3 days or until fluffy patchesappear on them (Fig. 1.8). These patchesmay be white, green, brown or of anyother colour. Observe the patches undera microscope or a magnifying glass.Paheli is keen to knowwhether her beautiful shoes,which she wore on specialoccasions, were spoiled by fungiduring the rainy season. Shewants to know how fungi appearsuddenly during the rainyseason.6SCIENCE