Chapter 6: Proteins
Student Learning Outcomes
1. Describe the structure and role of amino acids; distinguish essential from nonessential
amino acids and explain why adequate amounts of each of the essential amino acids are
required for protein synthesis.
2. Describe how amino acids are organized and used to form proteins.
3. Identify food sources of protein, distinguish between high-quality and low-quality
proteins, and describe the concept of complementary proteins.
4. Plan a health plant-based eating pattern than meets the body’s nutritional needs.
5. Describe how protein is digested, absorbed, and metabolized in the body.
6. List the primary functions of protein in the body.
7. Apply current recommendations for protein intake to determine protein needs for healthy
adults, and descrive what is meant by postivie protein balance, negative protein balance,
and protein equilibrium.
8. Describe several health concerns related to protein intake, including protein-calorie
malnutrition, food allergies, kidney disease, and inborn errors of metabolism.
9. Define nutritional genomics.
Fact Check: Should I Take Collagen for Healthy Skin?
● Collagen supplements are purported to promote skin elasticity and support bone and
joint health
● The collagen found in dietary supplements comes from cows, pigs, chickens, and fish
and has be hydrolyzed (broken down into small peptides) to promote absorption. Once
absorbed, these raw materials can then be used to synthesize collagen in cells if it is
needed.
● Although preliminary studies suggest the collagen supplements can increase skin
elasticity and enhance wound healing, it is unclear what dose of collagen or combination
of other ingredients is necessary to achieve these results.
Section 6.1 Concepts: Amino Acids-Building Blocks of Proteins
1. Describe the basic structure of an amino acid?
2. What is the difference between the essential and nonessential amino acids?
3. What are some examples of conditions in which a nonessential amino acid becomes
essential?
Overview of Protein
Body made up of thousands of proteins.
Contains nitrogen, carbon, hydrogen, and oxygen.
North Americans generally consume more than they need to maintain health.
Functions:
● Forms important structures in body
● Makes up key part of blood
● Regulates and maintains body functions
● Provides essential nitrogen (in the form of amino acids)
, ● Can fuel body cells
Amino Acids-Building Blocks of Proteins
20 different amino acids made up all proteins
● Contain nitrogen, carbon, hydrogen, and oxygen
Nine essential amino acids
● Not synthesized, must be consumed from diet 11 nonessential amino acids
● Can be synthesized in body
Typically supply 4 kcal per gram
Protein Functions:
● Regulates and maintains body functions
Essential Amino Acids
Nine essential amino acids
● Cannot be synthesized by humans in sufficient amounds ot at all, must be included in
the diet
Limiting amino acid
● Essential amino acid in lowest concentration in food or diet relative to body needs
Conditionally essential amino acids
● Nonessential amino acids that become essential during certain situations (For example,
rapid growth, disease, metabolic stress)
● Most plant sources of protein are incomplete proteins. However, soy protein is a
complete protein.
● Soy products such as soy milk, tofu, and edamame provide a plant source of all the
essential amino acids
Branched-Chain Amino Acids
Amino acids with branching carbon backbone
● Leucine, isoleucine, and valine
○ All areas essential amino acids
○ Used by muscles for energy needs
High amount of whey protein from milk.
● Popular with strength-training athletes
Section 6.2 Concepts: Protein Synthesis and Organization
1. With reference to protein synthesis, explain what happens during transcription and
translation.
2. Why is the order of the amino acids in a protein important?
3. What are some of the ways a protein can become denatured?
4. What is the difference between the genome and the epigenome?
Overview of Protein Organization and Synthesis
Proteins linked together by chemical bonds.
Peptide bonds
Student Learning Outcomes
1. Describe the structure and role of amino acids; distinguish essential from nonessential
amino acids and explain why adequate amounts of each of the essential amino acids are
required for protein synthesis.
2. Describe how amino acids are organized and used to form proteins.
3. Identify food sources of protein, distinguish between high-quality and low-quality
proteins, and describe the concept of complementary proteins.
4. Plan a health plant-based eating pattern than meets the body’s nutritional needs.
5. Describe how protein is digested, absorbed, and metabolized in the body.
6. List the primary functions of protein in the body.
7. Apply current recommendations for protein intake to determine protein needs for healthy
adults, and descrive what is meant by postivie protein balance, negative protein balance,
and protein equilibrium.
8. Describe several health concerns related to protein intake, including protein-calorie
malnutrition, food allergies, kidney disease, and inborn errors of metabolism.
9. Define nutritional genomics.
Fact Check: Should I Take Collagen for Healthy Skin?
● Collagen supplements are purported to promote skin elasticity and support bone and
joint health
● The collagen found in dietary supplements comes from cows, pigs, chickens, and fish
and has be hydrolyzed (broken down into small peptides) to promote absorption. Once
absorbed, these raw materials can then be used to synthesize collagen in cells if it is
needed.
● Although preliminary studies suggest the collagen supplements can increase skin
elasticity and enhance wound healing, it is unclear what dose of collagen or combination
of other ingredients is necessary to achieve these results.
Section 6.1 Concepts: Amino Acids-Building Blocks of Proteins
1. Describe the basic structure of an amino acid?
2. What is the difference between the essential and nonessential amino acids?
3. What are some examples of conditions in which a nonessential amino acid becomes
essential?
Overview of Protein
Body made up of thousands of proteins.
Contains nitrogen, carbon, hydrogen, and oxygen.
North Americans generally consume more than they need to maintain health.
Functions:
● Forms important structures in body
● Makes up key part of blood
● Regulates and maintains body functions
● Provides essential nitrogen (in the form of amino acids)
, ● Can fuel body cells
Amino Acids-Building Blocks of Proteins
20 different amino acids made up all proteins
● Contain nitrogen, carbon, hydrogen, and oxygen
Nine essential amino acids
● Not synthesized, must be consumed from diet 11 nonessential amino acids
● Can be synthesized in body
Typically supply 4 kcal per gram
Protein Functions:
● Regulates and maintains body functions
Essential Amino Acids
Nine essential amino acids
● Cannot be synthesized by humans in sufficient amounds ot at all, must be included in
the diet
Limiting amino acid
● Essential amino acid in lowest concentration in food or diet relative to body needs
Conditionally essential amino acids
● Nonessential amino acids that become essential during certain situations (For example,
rapid growth, disease, metabolic stress)
● Most plant sources of protein are incomplete proteins. However, soy protein is a
complete protein.
● Soy products such as soy milk, tofu, and edamame provide a plant source of all the
essential amino acids
Branched-Chain Amino Acids
Amino acids with branching carbon backbone
● Leucine, isoleucine, and valine
○ All areas essential amino acids
○ Used by muscles for energy needs
High amount of whey protein from milk.
● Popular with strength-training athletes
Section 6.2 Concepts: Protein Synthesis and Organization
1. With reference to protein synthesis, explain what happens during transcription and
translation.
2. Why is the order of the amino acids in a protein important?
3. What are some of the ways a protein can become denatured?
4. What is the difference between the genome and the epigenome?
Overview of Protein Organization and Synthesis
Proteins linked together by chemical bonds.
Peptide bonds
