BIOLOGY 156 LAB EXAM 1 QUESTIONS
AND ANSWERS
pH is the measurement of the hydrogen concentration in a solution. A difference
in one ph unit represents a 10 fold change in acidity
What is a pH? What does it measure?
A buffer is a solution that resists changes in pH when acid or alkali is added to it.
Buffers typically involve a weak acid or alkali together with one of its salts. An
example of a buffer in the blood stream is carbonic acid and Bicarbonate anion
What is a Buffer? Give an example found in the blood stream
7.35 and 7.45
What is the average blood pH?
Tests for the presence in sugar in an unknown solution. Orange/yellow is positive
Blue/green is negative
Whats is the Benedict's test? What color means substance is present and what
color means it is absent?
Iodine. Lugol's Solution. Positive = blue-black solution. Negative = brown-orange
What specific molecule reacts with starch? What solution contains this molecule?
What are the positive and negative colors
A red-colored dye used to identify fats in solution. It is lipid soluble and stains lipid
+ solutions red. Postive = Red Negative = will not dissolve and remain a black
powder
, What is Sudan IV? What is its special characteristic? What are the positive and
negative colors?
Sodium Hydroxide and Copper Sulphate. The copper ions react with the amino
groups in the protein. Positive = Purple Negative = Blue
What molecules test for protein in a solution? What happens when there is
protein in a solution? What are the colors for a positive and negative solution?
Carbon, Oxygen,Hydrogen and Nitrogen
What are the 4 most abundant elements in living organisms?
a) Fatty Acids
b) Nucleotides
c) Amino Acids
d) Monosaccharides
List the small molecule that composes the following: a)Lipids-fats-triglycerides,
b)DNA-RNA, c)Proteins, d)Polysaccharides
Contains a buffer, breaks down in stomach and releases anions and cations.
Anions combine with H+ ions to form another compound in turn removes some
H+ atoms in stomach and raises pH
How does taking an antacid tablet help an "acid stomach"?
Test hamburger with CuSO4 and NaOH. Prepare a ew solutions with known
amounts of protein (1g, 2g, 3g etc). Test each with solution - creates a color scale.
Test a known amount of patty and compare color to color scale
How would you determine how much protein is present in 1g of a hamburger
patty?
Enzymes are biological catalysts that speed up the rate of specific chemical
reactions. Enzymes bind to a specific region of a substate to produce specific
products
AND ANSWERS
pH is the measurement of the hydrogen concentration in a solution. A difference
in one ph unit represents a 10 fold change in acidity
What is a pH? What does it measure?
A buffer is a solution that resists changes in pH when acid or alkali is added to it.
Buffers typically involve a weak acid or alkali together with one of its salts. An
example of a buffer in the blood stream is carbonic acid and Bicarbonate anion
What is a Buffer? Give an example found in the blood stream
7.35 and 7.45
What is the average blood pH?
Tests for the presence in sugar in an unknown solution. Orange/yellow is positive
Blue/green is negative
Whats is the Benedict's test? What color means substance is present and what
color means it is absent?
Iodine. Lugol's Solution. Positive = blue-black solution. Negative = brown-orange
What specific molecule reacts with starch? What solution contains this molecule?
What are the positive and negative colors
A red-colored dye used to identify fats in solution. It is lipid soluble and stains lipid
+ solutions red. Postive = Red Negative = will not dissolve and remain a black
powder
, What is Sudan IV? What is its special characteristic? What are the positive and
negative colors?
Sodium Hydroxide and Copper Sulphate. The copper ions react with the amino
groups in the protein. Positive = Purple Negative = Blue
What molecules test for protein in a solution? What happens when there is
protein in a solution? What are the colors for a positive and negative solution?
Carbon, Oxygen,Hydrogen and Nitrogen
What are the 4 most abundant elements in living organisms?
a) Fatty Acids
b) Nucleotides
c) Amino Acids
d) Monosaccharides
List the small molecule that composes the following: a)Lipids-fats-triglycerides,
b)DNA-RNA, c)Proteins, d)Polysaccharides
Contains a buffer, breaks down in stomach and releases anions and cations.
Anions combine with H+ ions to form another compound in turn removes some
H+ atoms in stomach and raises pH
How does taking an antacid tablet help an "acid stomach"?
Test hamburger with CuSO4 and NaOH. Prepare a ew solutions with known
amounts of protein (1g, 2g, 3g etc). Test each with solution - creates a color scale.
Test a known amount of patty and compare color to color scale
How would you determine how much protein is present in 1g of a hamburger
patty?
Enzymes are biological catalysts that speed up the rate of specific chemical
reactions. Enzymes bind to a specific region of a substate to produce specific
products
