Exam III Study Guide Lecture 15 Human Uses of Plants I Early Sites of Agriculture Intro to Agriculture the science art and practice of cultivating the soil producing crops and raising livestock A the near East the fertile crescent of Mesopotamia B C New World modern day South American and Peru potato cacao Mexico beans corn tomato the far East Southeast Asia the Yellow and Yangtze rivers D Modern agriculture 3 of the planet s land 97 of the land is non crop or non grazing its tundra desert forest mountain and tropical forest E Agriculture in the US land area is 1 9 billion acres 16 is used as crop land 34 is used for pasture peppers squash and grazing a Four major crops are planted on 80 of crop land corn wheat soy beans and hay b Vegetables fruits nuts are produced on 7 of the crop land cotton on 4 of the land c Steady increase in agriculture b c of improved crop varieties practices pest control and tailored fertilization of crops II Human Nutrition A Macronutrients 3 a Carbs 4cal g composed of i Monosaccharides basic building block glucose is metabolized during cellular respiration to produce energy fructose and galactose ii Disaccharides composed of 2 monosaccharides joined together sucrose is the most glucose fructose sucrose others include lactose milk sugar maltose found in germinating grains no nutritional value iii Polysaccharides contain hundreds of thousands of individual sugar units complex carbs starch long glucose chain found stored in plants potato wheat rice glycogen storage form of glucose in the human body excess glucose is converted into fat 1 Fiber derived from plants comes from cellulose not digestable but provides bulk dietary fiber can be soluble found in oat reduces cholestrol levels and risk of heart disease insoluble found in fruit bran vegetables absorbs water prevents constipation and may prevent certain cancers colorectal i Large complex molecules made from amino acids there are 20 ii Cells in the body take 11 out of 20 amino acids but 11 amino acids cannot be made iii 9 essential ones must come from the diet iv complete proteins contain all the essential amino acids animal sources are complete proteins from plant sources are incomplete combine different protein plant sources to get all essential ones v digestion requires digestive enzymes some proteins egg cannot be broken down high quality proteins contain all essential can be digested free their amino acids b Protein 4cal g c Fats 9 cal g i Saturated vs unsaturated 1 Depends on carbon hydrogen bonding of fatty acid chain carbon atoms are joined by a single bond saturated double bonds are unsaturated 2 Saturated solid room temp butter lard beef fat 3 Unsaturated liquid room temp corn oil olive oil 4 Unsaturated fats lower risk of 3 disease by lowering cholestrol levels Omega 3 fatty acids ii Cholestrol 1 Subcategory of lipids called steroids important for making cell membranes and human hormones 2 Eggs butter meat cheese high chol 3 Good vs bad cholestrol LDL bad HDL good helps decrease LDL B Micronutrients required in small amounts 2 kinds a Vitamins i Vitamin A formation of vision pigments healthy skin bone tooth development animal sources liver plant sources yellow orange dark green fruits lack of causes night blindness lack of bone growth ii Vitamin B complex 8 vitamins all water soluble act as coenzymes help in food breakdown release of energy deficiency causes fatigure weakness depression anemia good sources meat fish chicken whole grains seeds B12 only from animals iii Vitamin C important role in synthesis of collagen connective tissue of cells found in bones teeth good antioxidant helps in absorption of iron lack causes scurvy bleeding gums fatigue brittle bones iv Vitamin D helps to regulate calcium and phosphorus levels in normal bone development can be synthesized on exposure to sunlight lack causes bone malformation called rickets does not occur in plants milk dairy products b Minerals i calcium most abundant lack causes osteoporosis milk dairy products are good ii iii sources iron trace mineral needed in smaller amounts functions as component of hemoglobin molecule that carries oxygen in red blood cells lack can cause anemia good sources are liver fish poultry leafy veggies dried fruits legumes iodine trace mineral required for the formation of thyroid hormones lack causes goiter swelling of the thyroid gland iodized salt is best source III Dietary Guidelines A Food Pyramid Lecture 16 Grasses Legumes Starchy Staples I Grasses make up 25 of world s vegetation monocots herbaceous parallel leaf venation flower parts in three s scattered vascular bundles fibrous roots A include grains edible grains of cultivated grasses cereals major suppliers of calories advantage dry seeds can be stored for years concentrated food source B Flowers of grasses inflorescence is the structure containing all the flowers perfect bisexual wheat or rice imperfect unisexual corn wind pollination anthers are large produce a lot of pollen stigmas are double large to catch pollen C Grass fruit have simple dry fruits that do NOT open maturity caryopsis seed coat is fused to the ovary wall corn wheat rice dries until it s 5 15 water can withstand extreme cold heat grain parts include 1 endosperm 3n large cells filled with starch grains supplies food to germinating seedling 2 embryo or germ 2n young plant rich in oils proteins vitamins 3 bran outer layers of old fruit wall seed coat and aleurone layer secretes enzymes that digest the stored starch in the endosperm rich in protein vitamins D Wheat most widely cultivated grain cool dry climate origin wild wheat species found in near east crossed forming polypoid species that are used today i Types durum pasta bread wheat high gluten protein that gives bread elasticity together with a leavening agent yeast or baking soda is added to produce CO2 bubbles which are trapped and make the dough rise ii Wheat nutrition great source of carbs and fiber contains 13 protein concentrated in the bran and germ iii Corn or maize origin central Mexico thought to have evolved from Teosinte has a tassel inflorescence or group of male flowers end of the stem has an ear inflorescence of female flowers on a lateral branch silks coming from the ears are the individual stigmas of each female flower each attached to an ovule will become a seed flour corn soft endosperm easy to grind 1 popcorn oldest type of corn hard seed coat w high interal moisture 2 3 dent corn soft starch in the center hard