Products of Photosynthesis

Fate of Products of Photosynthesis  Glucose used in respiration to produce energy  Glucose converted to more complex carbohydrates and stored, e.g. Sucrose Starch  Oxygen used in respiration or lost to air

Carbohydrates  Chemical compounds that contain O, H, and C atoms.  Consist of monosaccharides - simple sugars e.g. glucose, fructose, galactose  2 monosaccharides – e.g. sucrose, maltose, lactose  More than 2 – e.g. starch, cellulose, glycogen disaccharide polysaccharide

Monosaccharides  Simplest form of carbohydrates.  Consist of one sugar  Usually colorless, water-soluble, crystalline solids.  Some have a sweet taste.

Disaccharides  Composed of two monosaccharides  Like monosaccharides, they are crystalline, water-soluble, and sweet-tasting

Polysaccharides- Complex Carbohydrates  Polymers made up of many monosaccharides  Starch consists of several hundred glucose mols; insoluble in water  Glycogen is the storage form of glucose in animals  Cellulose is the structural components of plants

How to Distinguish between some Common Sugars  Glucose and fructose are reducing sugars  Benedict's reagent is used to determine if a reducing sugar is present. If it is a reducing sugar, the mixture will turn green/orange/red.  Sucrose is not a reducing sugar

Heterotrophic Nutrition

 Includes the activities by which organisms unable to manufacture organic molecules obtain and process preformed organic molecules from their environment.

Processes for Heterotrophic Nutrition  Ingestion – mechanisms by which take in food  Digestion is the process of breaking down food into molecules small enough for the body to absorb. Proteins, carbohydrates, and fat in our diets must be broken down and later, reassembled in forms useful to our body.

Processes for Heterotrophic Nutrition cont’d  Digestion Mechanical digestion – process by which foods are physically broken down to increase surface area for enzyme action, e.g. chewing, tearing, grinding, cutting Chemical digestion – process by which foods are broken down chemically by enzymes into simpler molecules; process called hydrolysis.  Egestion – process by which indigestible components of food are eliminate from the body.

Human Digestive System