PROTEINS
What is the primary site of protein digestion?
Small intestine
Which of the following conditions may result in a negative nitrogen balance?
Illness or injury
An amino acid that can form a special covalent bond called disulfide bond:
cysteine
Ceruloplasmin is a type of:
metalloprotein
What is the role of hydrochloric acid (HCl) in protein digestion?
Denaturing proteins
Which protein plays a role in regulating the nervous system and has antioxidant properties?
Taurine
What is the process by which the liver converts the carbon skeleton of certain amino acids into ketone bodies?
Ketogenesis
The most abundant protein in the human blood plasma.
albumin
Limiting amino acid in legumes:
methionine
A form of extreme undernutrition brought about by lack of calories and protein
marasmus
Which group of proteins includes antibodies and is involved in defending the body against infections?
Globulins
A conditionally essential amino acid:
tyrosine
What is nitrogen balance?
The difference between nitrogen intake and nitrogen excretion
Which type of protein is responsible for transporting lipids such as cholesterol and triglycerides in the blood?
Lipoproteins
Which of the following amino acids is involved in the transport of fatty acids into the mitochondria for energy production?
Carnitine
What is the significance of a positive nitrogen balance in athletes?
It may indicate muscle growth and repair
Which of the following is not a function of taurine?
Muscle contraction
What is the final product of protein digestion?
Amino acids
What is a negative nitrogen balance?
Nitrogen intake is less than nitrogen excretion
Which hormone stimulates the secretion of gastric acid and pepsinogen?
Gastrin
The protein found in human hair and finger nails as well as in horns, claws, and beaks of bird:
keratin
A branched-chain amino acid:
isoleucine
Intermediate of methionine metabolism which elevated levels has also been suggested to cause oxidative damage
homocysteine
Which enzyme, produced in the pancreas, further breaks down peptides into individual amino acids in the small intestine?
Trypsin
The enzyme pepsin is not denatured in the stomach despite the very acidic environment attributed to hydrochloric acid. How can this be?
pepsin is the only protein-enzyme that functions best in an acidic environment
A measure of protein quality that refers to the relative utilization of the protein in the body compared to a standard protein:
Biological Test
The index used to indicate the amount of protein utilized by the body.
nitrogen balance
Enzyme that cleaves amino acids from the carboxyl ends of the polypeptides
carboxypeptidase
Where does the majority of protein digestion occur in the digestive system?
Small intestine
All of the following are non-essential amino acids except:
Lysine
Which protein is involved in the transport of iron?
Transferrin
Which hormone stimulates the secretion of gastric acid and pepsinogen?
Gastrin
Which protein is involved in blood clotting and is converted to fibrin to form a mesh that stops bleeding and promotes wound healing?
Fibrinogen
A measure of protein quality that refers to the relative utilization of the protein in the body compared to a standard protein:
Biological Test
A form of extreme undernutrition brought about by lack of calories and protein
marasmus
What is the first step in protein digestion?
Breakdown by enzymes in the stomach
Which enzyme, produced in the pancreas, further breaks down peptides into individual amino acids in the small intestine?
Trypsin
Which of the following conditions may result in a positive nitrogen balance?
Recovery from illness or injury
What is the process by which the liver converts the carbon skeleton of certain amino acids into glucose?
Gluconeogenesis
An amino acid that can form a special covalent bond called disulfide bond:
cysteine
Which of the following conditions may result in a negative nitrogen balance?
Illness or injury
Which of the following proteins is involved in maintaining oncotic pressure in the blood?
Albumin
The acceptable macronutrient distribution range (%) of proteins based on TER (as shown in FEL) is:
10-15%
How does the process of acidification affect proteins in meat when subjected to an acidic environment, such as marination in vinegar or citrus juices?
It denatures the proteins, altering their structure and texture.
The most abundant protein in the human blood plasma.
albumin
All of the following are non-essential amino acids except:
Lysine
The protein found in human hair and finger nails as well as in horns, claws, and beaks of bird:
keratin
What is the primary function of the small intestine in protein digestion?
Absorption of small peptides and amino acids
The index used to indicate the amount of protein utilized by the body.
nitrogen balance
Limiting amino acid in legumes:
methionine
All of the following are essential amino acids except:
Glycine
What is the inactive precursor of pepsin?
Pepsinogen
Which group of proteins includes antibodies and is involved in defending the body against infections?
Globulins
Which of the following measures the amount of protein retained in the body after digestion and absorption?
Net protein utilization
Which of the following measures the amount of protein retained in the body after digestion and absorption?
Net protein utilization
Which protein is responsible for muscle contraction?
Actin
What is the end product of protein digestion?
Individual amino acids
Which enzyme is responsible for breaking down proteins in the stomach?
Protease
Which of the following protein sources has the highest biological value?
Beef
The principal nitrogen-excretion product of metabolism:
urea
Which of the following cells in the stomach produces pepsinogen?
Chief cells
Ceruloplasmin is a type of:
metalloprotein
All of the following are semi-essential amino acids except:
Glycine
How are individual amino acids absorbed in the small intestine?
Both B and C
Which enzyme is responsible for breaking down proteins in the stomach?
Protease
Which of the following amino acids is an imino acid?
proline
A conditionally essential amino acid:
tyrosine
Which of the following is a potential consequence of excess protein intake?
Kidney damage
All of the following are essential amino acids except:
Glycine
Where are the enzymes responsible for protein digestion produced?
Pancreas
Which of the following proteins is involved in maintaining oncotic pressure in the blood?
Albumin
What is the role of hydrochloric acid (HCl) in protein digestion?
Denaturing proteins
The protein found in human hair and finger nails as well as in horns, claws, and beaks of bird:
keratin
Which of the following amino acids is an imino acid?
proline
Which of the following is an example of a regulatory protein?
Insulin
Which type of protein is responsible for transporting lipids such as cholesterol and triglycerides in the blood?
Lipoproteins
The removal of nitrogen-containing amino groups which are used to form ammonia
deamination
A transport protein:
albumin
Precursor of serotonin:
tryptophan
What enzyme is responsible for the breakdown of proteins in the stomach?
Pepsin
A branched-chain amino acid:
isoleucine
How does the process of acidification affect proteins in meat when subjected to an acidic environment, such as marination in vinegar or citrus juices?
It denatures the proteins, altering their structure and texture.
All of the following are semi-essential amino acids except:
Glycine
What is a negative nitrogen balance?
Nitrogen intake is less than nitrogen excretion
What is the primary function of the small intestine in protein digestion?
Absorption of small peptides and amino acids
What happens to undigested proteins that reach the large intestine?
They are excreted in feces.
Which of the following is responsible for transporting amino acids from the small intestine to the liver?
Portal vein
Precursor of serotonin:
tryptophan
What is a positive nitrogen balance?
Nitrogen intake is greater than nitrogen excretion
Which of the following is the final product of protein metabolism?
Urea
Which of the following is a derived protein?
Gelatin
Enzyme that cleaves peptide bonds next to lysine and arginine
trypsin
What is the primary nitrogenous waste product of protein metabolism?
Urea
What is the primary source of nitrogen in the body?
Proteins
What is the primary function of the liver in protein metabolism?
All of the above
The acceptable macronutrient distribution range (%) of proteins based on TER (as shown in FEL) is:
10-15%
Enzyme that cleaves amino acids from the carboxyl ends of the polypeptides
carboxypeptidase
The removal of nitrogen-containing amino groups which are used to form ammonia
deamination
Enzyme that cleaves peptide bonds next to lysine and arginine
trypsin
How are individual amino acids absorbed in the small intestine?
Both B and C