Carbohydrate Lab
A.Biology
A. Introduction:
1. Give 3 examples of food that have
carbohydrates in them:
a.
b.
c.
2. List 2 ways that carbohydrates are used in
Your body:
a.
b.
3. Examine the word carbohydrate.
a. What do you think the “carbo” refers
to?
b. What do you think the “hydrate” refers
to?
4. Complete the Carboydrate Chart:
Carbohydrate
Meaning of Term Examples(List 3)
Type
Monosaccharide
Disaccharide
Polysaccharide
B. Monosaccharides – “simple sugars”
1. What 3 elements are present in simple
sugars?
2. How many atoms of carbon are in
monosaccharides?
3. Write the chemical formula for:
Glucose
Fructose
Galactose
(HINT: Always write C, then H, then O. Then
place a number as a subscript after each symbol
to show the number of atoms present)
4. Compare the number of hydrogen atoms to
the number of oxygen atoms in each sugar.
What is the ratio?
What compound does the ratio look like?
5. Look at the arrangement of the C,H,O atoms
in glucose, fructose and galactose. (Refer to
the model sheet).
a. What makes the three simple sugars
different?
b. Glucose, fructose and galactose are
isomers meaning that they are identical
in composition but different in
C. Dissacharides/Double Sugars
1. When 2 monosaccharides _______, a
dissacharide forms
2. Examples of Dissacharides:
a. glucose and glucose form
b. glucose and fructose form
c. glucose and galactose form
3. Construct a molecule of:
a. sucrose
b. maltose
DIRECTIONS FOR CONSTRUCTING:
1. Cut out the paper models needed along
the solid lines
2. Cut an “OH” from 1 model and an “H”
from the other model (Do NOT throw
these away)
3. Join the paper models to form the
disaccharide model(they should fit like
pieces of a puzzle)
EQUATION WRITING(White drawing
paper)
1. Write the names of the reactants that are
forming the dissacharide
2. Place a plus sign between the 2 names
3. Draw an arrow going from the reactants
to the right of your paper
4. Glue the dissacharide to the paper to the
right of the arrow
5. Place a plus sign after the dissacharide
model
6. Glue the “OH” and “H” together to form
another compound
7. Name the products under the model
8. Give your equation a title
9. Repeat for the second dissacharide
4. Forming Dissacharides
a. What needs to be removed from the
monosaccharides so that they can combine to form a
dissacharide? ________ and _______
b. What new compound is formed in addition to
the dissacharide?
c. What is the chemical formula of a
dissacharide?__________(HINT: write as a CHO
compound)
d. What type of chemical reaction occurred in
your equations? ________________(Research
dehydration synthesis and hydrolysis)
D. Polysaccharides
1. When 3 or more _________molecules are
joined a polysaccharide is formed
2. Construct a 3 unit polysaccharide using the
following directions:
a. Cut out 3 glucose models
b. Remove a “H” from one model
c. Remove an “OH” from the other model
d. Remove a”H” and an “OH” from the
third model (DO NOT throw these
groups away)
e. Setting Up the Equation
1. On your white drawing paper write
the names of the reactants and place
plus signs between them
2. Draw an arrow pointing to the right
f. Gluing Products
1. Glue the 3 models together so they
fit like parts of a puzzle
2. Glue the “OH” and “H” groups
together to form another compound
3. Place a plus sign between the models
4. Name the products
5. Give the equation a title
SUMMARY:
1. What 3 elements make up all carbohydrates?
________________________________________
2. What is the ratio between H and O atoms in
carbohydrate and water molecules? _________
3. What small molecules make up all disaccharides?
_____________________
4. What small molecules make up all
polysaccharides? _____________
5. What common molecule is formed when
monosaccharide molecules are joined?
________________
6. What type of chemical reaction occurs when
monosaccharide molecules are used to build
dissacharides or polysaccharides?
_______________________________