Test 2 Objectives

Question 1

discuss the availability of fresh water on earth

Answer 1

less than 1% of water on earth is fresh water available for consumption

Question 2

list the top three uses of water in the United States

Answer 2

1. thermoelectric power
2. irrigation
3. public supply

Question 3

explain the water cycle by describing the movement of water between major reservoirs

Answer 3

-starts in ocean
-heat energy from the sun, evaporates and enters atmosphere
-cooler temperates in air, condense into clouds
-clouds get bigger and moist enough to release water, precipitates into ice caps and glaciers
-ice caps melt, runoff back into ocean

Question 4

discuss the benefits that floodplains provide for humans and ecosystems

Answer 4

store excess water, very fertile soils, reduce flood impact, filter stormwater, protect water quality

Question 5

compare groundwater and surface water as sources of fresh water for humans, including the methods used to extract water from these sources

Answer 5

groundwater: most of available freshwater, stored in aquifer pores and extracted by drilling and pumping, high to low energy
surface water: already on surface, high to low elevation

Question 6

describe how agriculture contributes to physical and chemical water pollution

Answer 6

fertilizers high in N and P

Question 7

explain the process of eutrophication and describe the harm that occurs as a result

Answer 7

nitrogen and phosphorous act as fertilizers and promote algae bloom.
as algae dies, it is decomposed by aerobic bacteria in water. bacteria use up oxygen in water and low dissolved oxygen (DO) levels result in dead zones (areas where large numbers of aquatic life have died from suffocation)

Question 8

explain how agricultural practices can be adjusted to reduce the amount of agricultural water pollution

Answer 8

changing fertilizer concentration or otherwise monitoring use

Question 9

name the six basic tastes and explain why each is important for humans to detect

Answer 9

1. sweet: sugar=quick energy
2. salty: maintaining body fluid levels
3. bitter: detecting toxic substances
4. sour: vitamin c
5. umami: protein and amino acids
6. fat: energy storage and essential fatty acids

Question 10

discuss how sensory information contributes to the formation of flavor images in our brains

Answer 10

smell and taste receptors send information to brain

Question 11

name the two types of starch produced in plants and discuss the role they play in staling bread

Answer 11

amylose: smaller, linear
amylopectin: larger, branched
dough is wet, water absorbed into crystalline structure of starch, bread dries

Question 12

name the four macronutrients that humans need to survive

Answer 12

1. water
2. carbs
3. proteins
4. fats

Question 13

describe the digestive process that occurs in the small intestine

Answer 13

accepts stomach contents, macros broken down by digestive enzymes and absorbed
4-hour process

Question 14

describe the digestive process that occurs in the large intestine

Answer 14

accepts small intestine contents, absorbs water and water-soluble salts, bacteria metabolize remaining nutrients and produce gas
week-long process

Question 15

name the three earliest cooking methods used and discuss the advantage of cooking food

Answer 15

1. dry roasting with fire
2. earth ovens (pits lined with stones)
3. boiling in water
   cooking kills pathogens, enhances flavor and texture

Question 16

discuss the advantages and disadvantages of the farming lifestyle compared to the hunter-gatherer lifestyle

Answer 16

hunter-gatherer: pros– consume less energy, work less; cons–more effort, unpredictable
farming: pros– all dietary needs met, consistent; cons–higher energy demands, physical labor

Question 17

explain the hypothesis that past climate may have influenced the shift away from hunting and gathering and toward farming

Answer 17

because hunter-gatherers followed food, they had no central settlement and were at the mercy of the climate, in terms of protection as well as food source. with farming they could store food for when sources were low, and could have permanent settlements to protect them from the elements

Question 18

describe the benefits and drawbacks of slash-and-burn agriculture in the neolithic era

Answer 18

Initially very fertile, but decline in fertility over time so they have to move and start over until the previous land is restored

Question 19

list three factors that influenced the ease with which agriculture was adopted by various societies

Answer 19

1. increased availability of farmland
2. food security
3. ability to settle

Question 20

name the innovations that led to a widespread adoption of agriculture ~5,000 years ago

Answer 20

discovery of metals, and subsequent availability of plows and other tools

Question 21

define landrace and explain how they arise and why they are valuable

Answer 21

landrace is variety of crop that is adapted to environmental conditions and agricultural practices of a specific geographic area
arise from selective breeding
help against pests, diseases, etc

Question 22

explain the process that Nikolai Vavilov used to identify the origins of diversity of modern crops

Answer 22

collected germplasm of domesticated plants and their wild relatives from all over the world

Question 23

explain how diversity in crops arises, why it is valuable to humans, and how seed banks protect crop biodiversity

Answer 23

develops via mutation or hybridization, promotes desirable traits, seed banks keep a supply of genetic material which can be used to breed

Question 24

describe the difference between wild wheat and domesticated what and explain how these differences helped humans

Answer 24

wild has smaller seeds, slower growth, lower yields, less gluten, and seeds detach easily
domesticated has larger seeds, faster growth, higher yields, more gluten, and retains seeds (which make them easier to harvest)

Question 25

describe the technological innovations that were required to make bread, and name their countries of origin

Answer 25

Egypt: yeast to leaven bread, flat-top ovens to bake
Greece: sifting to remove bran and make white flour, grindstones to make meal, domed ovens to bake

Question 26

name the two major cookware innovations that facilitated frying of foods, and name their countries of origin

Answer 26

Greece: ceramic pots and pans made of finer clay and fired at higher temperatures (withstand heat better); olive oil
China: cast iron from raw iron ore; sesame oil

Question 27

list two contributions of Jan Baptist van Helmont to cooking science

Answer 27

1. coined term “gas” in reference to “gas of wines” from fermenting grapes (same as CO2 from burning charcoal)
2. Suggested presence of digestive enzymes (“ferments”)

Question 28

explain how Robert Boyle’s research into air and pressure led to invention of pressure cookers by Dennis Papin

Answer 28

Boyle’s Law–inverse proportionality of pressure and volume
Pressure cookers–when temperature rises so does pressure and foods cook faster; added safety valve to release pressure before explosion

Question 29

describe the purpose of emulsifiers and explain how they work

Answer 29

purpose: stabilize emulsions
how: hydrophilic heads and lipophilic tails, create a barrier between hydrous molecules and fat molecules

Question 30

explain how the law of conservation of matter is demonstrated by Lavoisier’s formula “must of grapes=alcohol+carbonic acids”

Answer 30

mass lost by fermenting grapes is equal to mass of alcohol and carbonic acids released in the process
(mass of grapes before=mass of fermented grapes+products after)

Question 31

describe the food culture in 17th century Chine and how it differed from food culture in Europe

Answer 31

1. best chefs cooked for elite (same as Europe)
2. chefs also worked in tearooms, restaurants, etc (unique to China)
3. food and cooking as an art (lacked scientific influence of Europe)