PLANTS HAVE OTHER NUTRITIONAL REQUIREMENTS THE STORY BEYOND PHOTOSYNTHESIS

PLANTS HAVE OTHER NUTRITIONAL REQUIREMENTS THE NEED FOR MACRONUTRIENTS Photosynthesis provides Carbon, Hydrogen and Oxygen in the form of glucose C 6 H 12 O 6 What other macronutrients are needed? Write them in your exercise book & why we need them What is the difference between macronutrients & micronutrients? Give some examples of micronutrients

PLANTS HAVE OTHER NUTRITIONAL REQUIREMENTS NITROGEN-FIXING BACTERIA Nitrogen gas (N 2 ) makes up 78% of the atmosphere however, this is not in a form that most organisms can use. ENTER: Nitrogen-fixing bacteria!

PLANTS HAVE OTHER NUTRITIONAL REQUIREMENTS WEATHERING OF ROCKS Weathering of rocks involves the physical and chemical breakdown of rock particles that produces water-soluble mineral salts. So what! The pH of the soil affects the availability of these ions for uptake by plants. These mineral salts are inorganic compounds that are absorbed as ions into the roots of plants. What features of plants assist them in taking up mineral salts? Explain the processes involved.

PLANTS HAVE OTHER NUTRITIONAL REQUIREMENTS MYCORRHIZAL ASSOCIATIONS Symbiotic relationship between plant roots and mycorrhizal fungi. This relationship increases the effective root surface area for nutrient absorption. The mycorrhizal fungi act as extended root hair substitutes.

HETEROTROPHIC STRATEGIES Heterotrophs must obtain organic compounds by eating other organisms or their products

HETEROTROPHIC STRATEGIES Nutritional requirements of heterotrophs Carbohydrates & Lipids Vitamins (organic) Minerals (inorganic) Amino Acids 9 Essential Amino Acids Glucose used in cell respiration Lipids required for cell membranes Required for protein synthesis Must be included in diet as heterotrophs cannot make 13 required Used in enzymes 20 required Structural components & in enzymes & vitamins

HETEROTROPHIC STRATEGIES FOOD MUST BE DIGESTED (CLASS ACTIVITY) Remember you should have your own set of notes from pages 111 to 114 from Heinemann Biology 1 Textbook.