Amino Acids and Proteins

Question 1

Define the following terms: Isoelectric point

Answer 1

pH at which a molecule carried no net charge.

Question 2

Define the following terms: Zwitterion

Answer 2

moments of differing charge but net neutral

Question 3

Define the following terms: Amphoteric

Answer 3

serves as both an acid and base

Question 4

Define the following terms: Amino acid

Answer 4

essential molecules that build protein

Question 5

Define the following terms: Peptide bond

Answer 5

from acid group to amino groupof two animo acids

Question 6

Define the following terms: Complex or conjugated protein

Answer 6

more than 1 combined tertiary structure

Question 7

Discuss protein structures and classifications

Answer 7

Size: 6k-1m Da
Differential Solubility
Charge (more pos more easily disolved)
Adsorption (ability for water to cling to)
Specific binding to antibodies
Made of C, O, H, N, S. N sets apart from lipids and carbohydrates.

Question 8

Differentiate among protein structures:

Primary

Answer 8

Chain of amino acids

Question 9

Differentiate among protein structures:

Secondary

Answer 9

Linked by H-bonds. Beta sheets and Alpha helices. Alpha more common.

Question 10

Differentiate among protein structures:

Tertiary

Answer 10

Formed when attractions occur between the sheets and helices. Function is related to folding structure

Question 11

Differentiate among protein structures:

Quaternary

Answer 11

multiple tertiary structures together. Think Hemoglobin.

Question 12

Explain the process of digestion and absorption of dietary proteins

Answer 12

Pepsin breaking proteins into peptides. Peptides are broken into Amino acids by secretin in the intestines. Pancreas Acinar cells secrete enzymes to assist

Question 13

State the main physiologic functions of plasma proteins

Answer 13

Albumin: 54%
Globulins: 46%
Total protein - albumin = Globulins

Question 14

Identify the main site of synthesis for plasma proteins

Answer 14

Prealbumin: Liver and choroid plexus
Albumin: liver

Question 15

Discuss the degradation of amino acids

Transamination and oxidative deamination

Answer 15

Transamination: the transfer of an amino group from one molecule to another
deamination: the removal of an amino group from an amino acid or other compound

Question 16

Discuss the degradation of amino acids

Ketogenic and glycogenic amino acids

Answer 16

Ketogenic: can be oxidized to generate acetyl-CoA

glycogenic amino acids: an amino acid that can be converted into glucose

Question 17

State the electrophoretic fraction in which each is located, the normal function, and disease states associated with abnormal levels

Albumin

Answer 17

Function: oncotic pressure
Disease: Liver disease, renal disease, dehydration, malnutrition

Question 18

State the electrophoretic fraction in which each is located, the normal function, and disease states associated with abnormal levels

Alpha-1-antitrypsin

Answer 18

Synthesized in: liver
protects elastin in the lungs by inhibiting elastase
diseases: inflammitory disease

Question 19

State the electrophoretic fraction in which each is located, the normal function, and disease states associated with abnormal levels

Alpha-2-macroglobulin

Answer 19

synthesized in the liver
serine protease inhibitor
Decreased in: acute pancreatitis, prostate cancers, inflam disorders
Increased in: nephrotic syndrome, contraceptive use, pregnancy and estrogen therapy

Question 20

State the electrophoretic fraction in which each is located, the normal function, and disease states associated with abnormal levels

Haptoglobin

Answer 20

Function: transport protein (free hemoglobin)
increased in: inflam disease, burns, trauma
Decreased in: intravascular hemolysis, liver disorders

Question 21

State the electrophoretic fraction in which each is located, the normal function, and disease states associated with abnormal levels

Ceruloplasmin

Answer 21

function: transport protein (copper)
increaded in: inflam, severe infection, tissue damage
Decreased in: (primary) Wilson’s disease. (secondary) malnutrition/malabsorption, liver disease, nephrotic syndrome

Question 22

State the electrophoretic fraction in which each is located, the normal function, and disease states associated with abnormal levels

Transferrin

Answer 22

Function: transport protein (iron)
increased: Iron deficiency
decreased: iron overload

Question 23

State the electrophoretic fraction in which each is located, the normal function, and disease states associated with abnormal levels

Fibrinogen

Answer 23

Function: clot when activated by thrombin
increased: infection, pregnancy
decreased: coagulation

Question 24

State the electrophoretic fraction in which each is located, the normal function, and disease states associated with abnormal levels

C-reactive protein

Answer 24

Function: stimulates tissue factor, causing coagulation and activating complement
Should be none
increased: tissue damage

Question 25

Correlate disease states and disorders associated with total protein levels and other test results

Answer 25

Hypoproteinemia: TP less than ref range. Any condition with a negative Nitrogen balance. Caused by excessive loss, decreased intake/synthesis, or accelerated breakdown of proteins

Hyperproteinemia: TP greater than ref range. Caused by dehydration or overproduction of gamma globulins

Question 26

State the reference range for serum total protein and albumin.

Answer 26

TP: 6.5-8.3 g/dl in adults
Albumin 3.5-5.5 g/dl