Download Organic molecules

Worksheet 3: Organic molecules
This section will dealt with the main organic molecules in living things:
carbohydrates, fats ( lipids ), proteins and nucleic acids.
A)
Web site name: Florida Community College Jacksonville
Web URL: http://web.fscj.edu/David.Byres/foodfiles.htm
Read “Carbohydrates”
1)
What does the body use carbohydrates for? ________________________
2)
What two chemicals are given out when carbohydrates are burned?
____________________________________________________________
3)
Why can cows survive on grass, but not humans? ____________________
_____________________________________________________________
_____________________________________________________________
Move down to the section “How sweet is your sugar?”
4)
What is the sweetest chemical listed here? __________________________
5)
Lactose is found in milk. Why does milk not taste very sweet?
_____________________________________________________________
6)
Plants and animals typically contain a lot of glucose. Most soft drinks such
as Coke, Pepsi and Sprite contain fructose instead of glucose. Why is this?
_____________________________________________________________
_____________________________________________________________
B)
Web site name: John Jay College; New York
Web URL: http://web.jjay.cuny.edu/~acarpi/NSC/11-nutrients.htm
(or http://www.visionlearning.com/library/module_viewer.php?mid=61
Read the section “Nutrients and Biochemistry”
7)
What three chemical elements are found in carbohydrates? _____________
_____________________________________________________________
8)
Look at the diagram of glucose. How many Carbon (C) atoms does it have?
_____________________________________________________________
9)
What two molecules are joined to form sucrose?
_____________________________________________________________
10)
What is the difference between starch and glycogen? __________________
_____________________________________________________________
11)
List four common foods that contain starch : _________________________
_____________________________________________________________
C)
Web site name:
Health Check Systems
Web site address: http://www.healthchecksystems.com/label.htm
12)
How many calories are there in 1 gram of carbohydrate?___________
1 gram of fat?
13)
___________
Why are “Krispy Krunchies” not a very healthy choice of food? _________
_____________________________________________________________
_____________________________________________________________
Look at the “FDA Specifications for Healthy claims”
14)
Does “Fat-Free” really mean “no fat”? _____________________________
15)
What % of the Daily Values for Vitamin A, Vitamin C etc does food labeled
“Healthy” have to have? ____________ %
16)
Do you think any of these health claims on the chart are misleading? _____
If so, which ones? _____________________________________________
_____________________________________________________________
_____________________________________________________________
D)
Web site name: John Jay College; New York
Web URL: http://web.jjay.cuny.edu/~acarpi/NSC/11-nutrients.htm#fat
Read “Fats” (Lipids)
17)
What two molecules react to make up a fat?
_______________________ and ____________________________
18)
List three functions of fats and oils, apart from energy storage :
_____________________________________________________________
19)
What is the difference between saturated and unsaturated fatty acids?
_____________________________________________________________
_____________________________________________________________
20)
Which fats are particularly beneficial in the fight against heart disease?
_____________________________________________________________
E)
Web site name: New England Journal of Medicine
Web site address: http://content.nejm.org/cgi/content/abstract/337/21/1491
Read “Dietary Fat Intake and the Risk of Coronary Heart Disease in Women”
21)
How many women in the study suffered from heart attacks ( myocardial
infarction) ? ___________________________________________________
22) Was total fat intake is related to the risk of coronary disease?
_____________
23) How much does it reduce the risk of heart attack if women replace 5% of
energy from saturated fats with energy from unsaturated fats? _______%
(Saturated and trans unsaturated fats are found in animal products (meat, milk)
and margarine. Unsaturated fats are common in plants.)
F)
Web URL:
http://www.fda.gov/Food/ResourcesForYou/Consumers/NFLPM/ucm274590.htm
24)
What new type of fat is now listed on food labels? ____________________
25)
Why is this change being made? ___________________________________
26)
What type of foods contain this fat? ________________________________
27)
When must this new fat be added to food labels? _____________________
G)
Web URL:
http://www.elmhurst.edu/~chm/vchembook/568denaturation.html
28)
What is meant by “Proteins can denature”? _________________________
29)
_____________________________________________________________
What 3 things can denature a protein and disrupt its function?
1. ________________ 2. ________________ 3. __________________
H)
Web site name: Livestrong.com
Web URL:
http://www.livestrong.com/article/303329-the-best-sources-of-plant-protein/
30)
What are the best sources of plant protein? __________________________
http://www.livestrong.com/article/86743-dangers-protein-supplements/
31)
Many pharmacies and stores sell protein or amino acid pills as dietary
supplements. What are two problems that can be caused by eating too much
protein ? ______________________________________________________
32)
If you are on a diet and eating very little food, why should you include some
protein in your diet? ____________________________________________