1. Tuesday, October 06, 2015Tuesday, October 06, 2015Tuesday, October 06, 2015Tuesday, October 06, 2015

2.   Macro: provide the body with energy  Micro: provide the body with small amounts of chemicals needed in biochemical reactions What is the difference between macronutrients & micronutrients?

3.   Kilocalories  1 kcal = amount of energy needed to raise 1 kg of H 2 O by 1 o C  Kilocalories are known as Calories to consumers.  1 kcal = 1 Calorie  So… The number of Calories in a food indicates how much energy the food provides. Which units do we use to measure energy from macronutrients?

4.  1.Carbohydrates : C,H,O in a 1:2:1 ratio a.Basic unit is the monosaccharide b.Sugars: a.Simple carbs that are absorbed by the body quickly c.Starches: a.Complex carbs that provide the body with steadier, long lasting energy d.Carb Energy a.Most carbs provide the body with 4kcal per gram 3 major groups of macronutrients.

5.  Simple Sugars

6.  ss

7.   Complex Starches

8.  dd

9.   Basic unit = amino acids  4kcal per gram Proteins

10.   20 different amino acids arrange in numerous ways to make proteins.  Protein structure and function depend on this arrangement. Amino Acids

11.  dd

12.   The human body can make many of the amino acids.  The remaining amino acids are obtained from food.  essential amino acids = amino acids that must be obtained from food. Where do we get our Amino Acids

13.   Basic unit is the Lipid  fatty acids attached to glycerol  9kcal per gram Fats

14.   Phospholipid Bilayer of Your Cells Lipid Functions

15.   Energy Storage Lipid Functions

16.   Vitamins & Minerals  Do not provide energy directly  Play key roles in biochemical reactions responsible for:  releasing energy  structural formation Micronutrients

17.   Adult nutritional requirements  2000-2800 kcal per day  500 million people worldwide are nutritionally deficient  13 million people die of starvation each year Undernourishment

18.  World Hunger

19.   Lack of a specific type of nutrient  Examples:  Kwashiorkor (lack protein)  Scurvy (lack Vit. C)  Beri beri (lack Vit. B1)  Rickets (Lack Vit. D)  Goiter (Lack iodine) Malnutrition

20.   Food supplies worldwide are increasing.  More food available per person  Why are so many people starving.  Food increases are in countries that already produced enough food  Long drought, civil war, political stability make it difficult for the neediest countries to improve food production. World Food Supply

21.  1.Green Revolution : 1960’s Developments of new strains of wheat & rice More response to fertilizers and irrigation Resistant to disease, grow faster, survive in variety of climates Modern farming methods and machinery increased efficiency Greater crop yields Increase gains, decreases price Food Production and Economics

22.   Intended to help underfed nations feed themselves  However, farmers in developing nations:  do not adequate water supply to maintain the new crops  Do not have money to buy fertilizers  Do not own modern machinery  Side effect of Green Revolution:  Huge crop yields in developed nations drive down prices, resulting in poorer farmers receiving lower profit for their crops. Green Revolution (cont)

23.   crops grown for purpose of selling  Poor farmers in developing nations can’t sell crops to other poor people in their own country  These farmers choose crops that can be exported Cash Crops

24.  dd

25.  dd

26.   Oceans can provide approximately 100 million metric tons of food per year without damaging marine biomes.  Currently, over 90 million metric tons per year are harvested Food from the Water

27.   Aquaculture: commercially grown food in controlled water environment  Reduces the overfishing of oceans  Produces over 21 million metric tons of food  Fish, clams, oysters Aquaculture

28.  dd

29.   Historically, Preparing soil, planting seeds, and maintaining crops were done by hand  Industrialized Agriculture (mid-20 th Century)  Equipment powered by fossil fuels replaced human- powered tools Modern Farming Techniques.

30.   Able to feed 5 people in 1850 per farmer; now able to feed 78 people after industrialized agriculture Industrialized agriculture’s positive impact on food production

31.   Requires a large amount of energy, pesticides, and fertilizers Industrial agriculture’s negative impact on environment?

32.   Pesticides kill most pests, but a small portion of the pest population is genetically resistant and will survive.  These resistant pests are able to reproduce, passing on the gene that is resistant to pesticides.  Result: more resistant individuals within the population. Pesticide Resistance

33.   Homozygous Dominant: TT  Heterozygous: Tt  Homozygous Recessive: tt Revisiting Mendelian Genetics

34.   Grow 1 or 2 crops that get highest prices  Problems:  No genetic diversity  Vulnerable to disease  soil becomes depleted of nutrients What is monoculture farming? Does this have a positive or negative impact on environment?

35.   Driven by economics and international trade  Negative Results  Soil erosion  Deforestation  Hunger  War  Desertification Modern Agriculture

36.  1.Crop Rotation : changing your crops on a regular cycle a.Prevents soil from becoming depleted of nutrients b.Prevents the need for nitrogen-based fertilizers 3 main components of Sustainable Agriculture

37.  ss Nitrogen Fixing Legumes

38.   Wind and Flowing Water are main agents of erosion  When topsoil is eroded, organic and mineral nutrients are lost.  This is bad news for farmers. 2. Erosion

39.   Cover Crops  Non food crops planted between growing seasons.  Drip irrigation  Delivers small quantities of water directly to roots of plants  No drain off  Reduce tillage  Process of turning the soil so that lower layers are brought to the surface.  Excessive tillage causes erosion. Reducing Erosion

40.  dd Drip Irrigation vs Flood Irrigation

41.   IPM: integrated pest management  Alternative to pesticides  Use natural predators to control pest populations  Bats, lady bugs, wasps, viruses, bacteria 3. Pest Management

42.  dd