NTD 411 Exam 3

Which cells release pepsinogen?

Chief

Which digestive hormone stimulates the release of proteolytic zymogens from the pancreas into the small intestinal lumen?

Cholecystokinin

What is the term for those amino acids that can be made from the essential ones? If enough of the essential ones are available these can be made.

Conditionally essential/indispensable

Methionine, an essential amino acid, is required to make the amino acid cysteine. What is true about a situation in which methionine is present in unusually small quantities?

Cysteine becomes an essential amino acid and must be supplied by another source other than methionine

In which organ does urea genesis occur?

Liver

The synthesis of protein is called:

Protein anabolism

Which of the following is true about protein synthesis?

Protein synthesis occurs in the rough endoplasmic reticulum

Which nutrient plays a significant role as a coenzyme in aminotransferase reactions?

Pyridoxal phosphate

Which of the following digestive endproducts cannot be absorbed into enterocytes?

Short polypeptides

An elevated ALT and AST indicates that:

The liver may be sustaining damage

All of the following contribute to ammonia in the body except:

Transamination

Which enzyme converts the other proteolytic zymogens to their active forms?

Trypsin

What is the biochemical process called in which ammonia is disposed of and detoxified?

Urea cycle

Chymotrypsin requires which mineral cofactor to be active in proteolytic activity?

Zinc

What is true about the movement of amino acids from the enterocyte throughout the body?

Blood draining from the small intestine carries amino acids through the portal vein to the liver

The RDA for protein for protein for an adult is:

0.8 g/kg body weight

How many amino acids are needed for human synthesis?

20

How many amino acids are essential/indispensable

9

What can be used in medical nutrition therapy to reduce nitrogen load and build-up of urea in the blood when are person is experiencing kidney failure?

A mixture of alpha-ketoacids of essential amino acids

All of the following contribute to ammonia in the body:

A. Deamination of amino acids C. Ingestion of aged foods such as cheese and processed meats D. Deamination of glutamine and asparagine E. Conversion of urea secreted into the colon to ammonia by intestinal bacteria

The portion of the amino acid left after the amino group has been removed is called a:

Alpha-ketoacid

Which of the following is true about diet and protein synthesis?

Animal protein sources better promote protein synthesis than plant

Amino acids not metabolized by the organ mentioned in #20 are the ______ ones.

Branched chain

The enterocyte membrane that faces the lumen (place where food and nutrients pass through) of the small intestine is called the _____ membrane.

Brush border

Which of the following is true about transport of protein digestive end products through the enterocyte membrane facing the lumen?

Different categories of amino acids (basic, acidic, neutral, aromatic) each have their own transport proteins

Which of the following is true about protein and amino acid sources?

Eggs can supply all amino acid needs so a person would not need to eat any other protein sources to supply amino acids

You would expect to see all of the following in advanced liver disease except:

Elevated blood urea

Enzymes that break peptide bonds from the ends of the polypeptide toward the middle are called:

Exopeptidases

Which digestive tract hormone stimulates the release of HCl and pepsinogen by the stomach?

Gastrin

Which of the following is true about carbon skeletons of amino acids?

Glucogenic amino acid carbon skeletons can be used in gluconeogenesis to make glucose

Which combination of plant protein sourced would provide a complete protein source in protein complementation

Hummus containing chick peas and sesame paste

Which of the following promotes protein anabolism and amino acid uptake by tissues?

Insulin

Which of the following is true of the urea cycle?

It disposes of ammonia from deamination

What is the definition of quaternary protein structure?

It is the association of more than one polypeptide to form a functional protein

What is true about deamination?

It occurs at a high rate when a person is in the unfed state (not having eaten in a long time)

Which is the main organ within which transamination and deamination occur?

Liver

What is the factor that promotes the conversion of pepsin to pepsinogen?

Low pH of the stomach caused by HCl

What aspect of an amino acid's chemical structure distinguishes it from monosaccharides and fatty acids?

Nitrogen

What is the effect of the amino acid leucine on protein synthesis?

Promotes it