Answer:
a. The formula for finding the number of colonies in a given volume is,
CFU/ml, here CFU is the colony forming units or the number of colonies formed in a volume plated in ml × dilution
The dilution factor given in the question is 1 × 10⁻⁴ and the number of colonies given is 186. Therefore, the number of bacteria present in the given 1 ml of the milk is,
CFU/ ml = 186 / 1 × 10⁻⁴ = 186 × 10⁴.
Hence, the concentration of bacteria in the milk is 186 × 10⁴ CFU/ml.
b) The limit of the bacterial concentration in the pasteurized milk is 20000 CFU/ml, however, it can be seen that the sample of the milk possess more concentration of bacteria than the desired value. Therefore, the milk is not safe to drink by Public Health Standards.
Answer:
6.75l l/min
Explanation:
Streptomycin is extracted from the fermentation broth using an organic solvent in a counter current staged extraction unit.
for 5 stage counter current staged extraction unit for streptomycin
X5 = 0.2g/l
X0 = 10.0g/l
X5/X0 = 0.02
given
Xn/X0, E, and
n = 5
A estimate of E can be evaluated directly;
E = 1.8
= LKd/H
by substituting the given values; Kd = 40, H= 150l/min
then we have,
L;L = 1.8(150)/40
= 6.75l l/min
Cyclopropane is a highly strained molecule because the conformations of the cycloalkanes are influenced by the torsional, angle strain, and steric strain. Cycloalkanes, which comprises more than three atoms of carbons are not flat molecules, they are puckered.
The three and four-membered ring components exhibit angle strain and minimize the internal bond angles. The angle strain is generated when the bond angles deviate from the optimum tetrahedral angle, that is, 109.5 degree.
Torsional strain is a resultant of eclipsing interactions, and steric strain is attained when the atoms are forced too close to each other.
Answer:
C. Slide A, plant cells; Slide B, animal cells
Explanation:
The slide A has some organelles that are unique to plant cells, and are mostly found in plant cells. Organelles such as a cell wall and chloroplasts are unique features of plant cells. They are normally absent in animal cells.
Therefore, slide A, which has these cell organelles can be rightly labelled as "plant cells", while side B, which has these organelles missing, can be labelled as "animal cells".
