Proteins
To use amino acids for energy, the nitrogen must first be removed from the amino acid. This process is called __________. amine transfer transamination nitrogen exchange deamination
deamination
A key function of protein in the body is __________. improving the body's immune response by acting as allergens donating or picking up hydrogen ions in the blood moving across cell membranes to regulate fluid balance acting as a covitamin to increase reaction times of body processes
donating or picking up hydrogen ions in the blood
Denaturation of proteins changes their __________. primary structure sequence of amino acids weight shape
shape
Protein should make up between __________ of the day's total energy intake. 45% to 60% 5% to 10% 10% to 35% 50% to 70%
10% to 35%
There are _____ unique amino acids in the human body. 9 11 26 20
20
Vegetarian diets are at risk of being deficient in __________. protein and fiber folic acid and vitamin B12 iron and zinc beta-carotene and vitamin E
iron and zinc
Proteins differ from carbohydrates and lipids in that they contain ___________. magnesium iron nitrogen phosphorus
nitrogen
Vegetarian diets may reduce risk for __________. nutrient deficiencies type 1 diabetes osteoporosis stroke
stroke
Which of the following actions or activities will not cause a protein's structure to break down? Lightly marinating. Gently stirring. Adding alcohol. Beating or whipping.
Gently stirring.
The side chain of an amino acid differentiates one amino acid from another. True False
True
Amino acids are bound together by a chemical bond known as an amino acid bond to form proteins. True False
False
Approximately 50 percent of every protein molecule is composed of nitrogen. true false
False
How does the body use the protein once it has been ingested? Consider the following statements and select the correct ones regarding protein use. If calorie intake is inadequate, amino acids can be used for production of energy. Amino acids are used to create new proteins. If you ingest more protein than your body needs, the protein is stored in muscle. The liver uses amino acids to create glucose.
If calorie intake is inadequate, amino acids can be used for production of energy. Amino acids are used to create new proteins. The liver uses amino acids to create glucose.
Once amino acids have entered the amino acid pool, their primary metabolic fate is to become part of a protein produced within individual cells. But this is not the only possible metabolic fate for amino acids. Which of the following could not be a metabolic fate for an amino acid after it becomes part of the amino acid pool? It could be used for energy production. It could be stored intact to be used for protein production another day. It could be used to make body fat. It could be used to produce glucose.
It could be stored intact to be used for protein production another day.
Which of the following is true regarding the relationship between amino acids and protein? Protein is made of nonessential amino acids only. Protein is made of essential amino acids only. Protein consists of a carbon atom bound to hydrogen, an amine group, and a side chain. Protein is made of essential and nonessential amino acids.
Protein is made of essential and nonessential amino acids.
To estimate whether a person's protein intake is adequate to meet his or her protein needs, researchers __________. assess the individual's muscle tone and strength use a nitrogen-balance procedure monitor the individual's body weight monitor the individual's blood pressure
use a nitrogen-balance procedure
Once the instructions have been transcribed to mRNA, the mRNA leaves the nucleus and binds to a ribosome in the cytosol. The ribosome moves along the mRNA reading the code that begins the process of translation. Which of the following statements correctly describes the function of tRNA during translation? During translation, tRNA carries the mRNA to the ribosome. During translation, tRNA carries the gene's instructions to the ribosomes. During translation, tRNA collects and transports the amino acids to the ribosome. During translation, tRNA transfers the instructions to the DNA.
During translation, tRNA collects and transports the amino acids to the ribosome.
Deamination occurs mostly in the brain. True False
False
Which of the following statements is FALSE regarding nitrogen balance? People who are injured or starving excrete more nitrogen than they consume. Children are generally in positive nitrogen balance. Most healthy adults are in neutral nitrogen balance. Pregnant women usually consume less nitrogen than they excrete.
Pregnant women usually consume less nitrogen than they excrete.
Amino acids found in the amino acid pool __________. can be used for protein synthesis help to synthesize essential amino acids require protein supplements to maintain their resources must come from animal products
can be used for protein synthesis
Excess protein consumed is converted to __________. hormones body fat glycogen stores amino acid pools
body fat
A nonessential amino acid is made __________. from excess glucose from excess dietary protein by transferring the amino group from one amino acid to a keto acid. A keto acid is an amino acid without the amine group. from excess fatty acids
by transferring the amino group from one amino acid to a keto acid. A keto acid is an amino acid without the amine group.
Nitrogen that has been removed during deamination __________. is stored in the liver is converted to a fatty acid and stored as a triglyceride is converted to urea and excreted through the urine
is converted to urea and excreted through the urine
Protein consumed in excess of body needs __________. is stored as body fat is used to build muscle is converted into glucose and used for energy acts as a regulatory hormone
is stored as body fat
Which of the following amino acids are considered essential? leucine, isoleucine, and proline asparagine, tryptophan, and valine histidine, tyrosine, and alanine lysine, methionine, and threonine
lysine, methionine, and threonine
How do we determine whether we are in protein balance? measuring the amount of nitrogen excreted as urea measuring the amount of protein we consume in grams monitoring weight gain and weight loss over a period of weeks measuring the amount of nitrogen consumed with the amount of nitrogen excreted
measuring the amount of nitrogen consumed with the amount of nitrogen excreted