biology lab chemical composition of cells
Which of the following are components of a fatty acid?
A carboxyl group and a long hydrocarbon chain
Carbohydrates, like glycogen and cellulose, are examples of polymers. What is a polymer?
A chain of similar building blocks called subunits, or monomers
What is an emulsifier?
A substance that helps fat-soluble and water-soluble compounds mix together
Which enzyme catalyzes the breakdown of starch into sugars?
Amylase
Which of the following reagents is best suited for the detection of sugars?
Benedicts
Carbohydrate molecules consist of what three types of atoms?
Hydrogen,Carbon,Oxygen
How are lipids best defined?
Lipids are biological compounds that are not soluble in water.
A positive reaction for reducing sugar when detected with Benedict's reagent is indicated by
a change in color away from the blue of the reagent that varies.
What is a monomer?
a molecule that can be bonded to other identical molecules to form a polymer.
Proteins are polymers of ______.
amino acids
Why don't water and oil mix?
because water is polar and oil is non polar
The presence of proteins or peptides in a solution can be detected using _________ reagent.
biuret
Starch is best classified as a
carbohydrate
Proteins have many functions including
catalyst for chemical reactions, transport, support, motion, defense
Maltose is which type of carbohydrate?
disaccharide
Which of the following molecules can be formed when monosaccharides combine?
disaccharides,sucrose,polysaccharides,glycogen
Which of the following are examples of monomers?
fatty acids, monosaccharides, glycerol, amino acids
To test a solution for the presence of starch, ______ can be used
iodine
Which of the following molecules is completely insoluble in water?
lipids
Fructose is which type of carbohydrate?
monosaccharide
The three types of macromolecules that are used to build cells are carbohydrates, lipids, and
proteins
To test a solution for the presence of ______________ , Benedict's reagent can be used.
sugars
A positive reaction for protein with Biuret reagent is indicated by
the production of a purple color.
Triglycerides are composed of ___________ fatty acids and ___________ glycerol molecules.
three ; one
The difference between the structure of saturated fats and unsaturated fats is that ______.
unsaturated fats contain one or more double bonds between their carbon atoms
If an iodine test for starch is negative, what color would you expect to see in the tested sample?
yellow
Amylase is a(n)
enzyme
examples of proteins
enzymes, structural molecules, membrane channels, antibodies
The components of lipids that consist of long chains of carbon and hydrogen are called
fatty acids
Which of these occurs in both saturated and unsaturated forms?
fatty acids
What is the name given to a chain composed of many subunits, such as starch, cellulose, or a polypeptide?
polymer
Glycogen is which type of carbohydrate?
polysaccharide
Which type of molecule is starch?
polysaccharide
Varying shades of purple indicate a positive reaction for _____ when testing with Biuret reagent.
protein
Fatty acids without double bonds between their carbon and hydrogen molecules are called ______ fats
saturated
The difference between the structure of saturated fats and unsaturated fats is that ______.
saturated fats contain single bonds only between their carbon atoms
Fatty acids that contain double bonds between their carbon and hydrogen molecules are called ___________ fats.
unsaturated
Emulsifiers have a polar end and a nonpolar end that helps them to disperse lipids in ________ and other polar liquids.
water
A carbohydrate is a macromolecule that contains carbon, hydrogen, and oxygen in what ratio?
1:2:1
Which of these might be used to test for glucose in urine for a person with diabetes?
Benedict's reagent
Which of the following tests is best suited for the detection of fat and oils?
Brown Paper