QUESTIONS Casein degradation Completion 1. From a chemical standpoint, casein is
ID: 201848 • Letter: Q
Question
QUESTIONS Casein degradation Completion 1. From a chemical standpoint, casein is classified as a From a physical standpoint, calcium caseinate forms a when placed in a liquid. Calcium caseinate comes from After a 2. Extracellular hydrolytic enzymes that break apart proteins are called protein is broken down in that way, the smaller products are called 3. Assume that a polymer outside the cell is broken down by the appropriate enzymes. Before the cell can take in these smaller molecules, at least two proteins must be present in the cell's plasma membrane. These are and bond. 4. The type of covalent bond that connects adjacent amino acids making up a protein is called a 5. The substrate acted upon by the enzyme tested for in this part of Exercise 28 is 6. Microbial degradation of proteins is important in our environment. Controlling the growth and metabolic activity of microbes that degrade proteins is of especial concern to the industry 7. Protein hydrolysis is evident on skim-milk agar plates by This effect is produced because True-False (correct all false statements) 1. A positive proteolysis test is indicated by a blue zone surrounding the area of growth on skim-milk agar plates. 2. Of the three bacteria tested in this exercise, only the species of Proteus gave a strong positive reaction after the second laboratory period.Explanation / Answer
QUESTIONS:
Casein degradation
Completion
1. protein, precipitate, milk
2. exoenzymes (peptidases), peptides
3. carrier proteins and transmembrane channel proteins
4. peptide
5. skim milk
6. dairy
7. zones of clearing around growth,
bacteria growing on the skim milk agar plates is capable of hydrolysing caesin usings its exoenzymes
1. False, A positive proteolysis test is indicated by a clear zone surrounding the area of growth on skim-milk agar plates
2. True
Gelatin degradation
Completion
1. protein mixture, liquid, gel
2. gelatinases
3. gelatin
4. collagen, hydrolyses, water molecules into peptide bonds
5. Bacteriological agar
6. gelatin liquefaction, partial or total liquefaction of the inoculated tube even upon refrigeration, complete solification of inoculated tube upon cooling to lower temperatures.
7. negative control
1. True
2. True
QUESTIONS:
Completion
1. transmembrane channel proteins and carrier proteins
2. Enterobacteriaceae
3. Bromothymol blue, Prussian blue, deep forest green
4. citrate-positive (utilizing), citrate-negative, citrate-utilizing (positive)
5. wash out any nutrients in the previous inoculation medium, because their presence may lead to a color change in the Simmons' citrate agar (false positive).
6. the color of the medium changes from forest green to Prussian blue.
7. that the color of the medium remains unchanged
1. True
2. False, Of the two bacteria tested in this exercise, only the species of Eschericia gave a strong negative reaction.