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Right option is (a) 24 minutes

The explanation is: The generation time is the time interval required for the CELLS (or population) to divide.

G (generation time) = (time, in minutes or HOURS)/n(number of generations)

G = t/n

t = time interval in hours or minutes

B = number of bacteria at the beginning of a time interval

b = number of bacteria at the end of the time interval

n = number of generations (number of times the cell population doubles during the time interval)

b = B x 2^n (This equation is an expression of growth by binary FISSION)

Solve for n:

LOGB = logB + nlog2

n = \(\frac{log_b – log_B}{log2}\)

n = \(\frac{log_b – log_B}{.301}\)

n = 3.3 logb/B

G = t/n

Correct choice is (d) Dependent – Bubbles per minute Plant A and Plant B, Independent- Depth (in meters), Graph- Line plot

Easiest explanation: Dependent VARIABLE-

Bubbles per minute – the amount of bubbles produced will depend on how DEEP the plant is in the water. The variable that DEPENDS on another variable is the dependent variable.

Independent variable-

The depth in meters – you are controlling the depths at which you place the plants and observing what happens to the number of bubbles. Typically the variable you have CONTROL over is the independent variable.

Graph-

Line – we are measuring the change in bubble production over time. (Why not a bar? – There are some gradual changes that may be lost depending on our scale. Also, LINES are often more SIMPLE to read and less confusing).

The CORRECT answer is (b) (1823,8.9)

The explanation: In VARIANCE there is SMALL culture and bulk culture.

Small culture-

The SUM of values in the (X-x̅)^2 column = Ƹ(X-x̅)^2 = 16,403

Since there are 10 samples in this data set, n=10. Placing these values into the formula for CALCULATING the variance yields,

Variance = \(\frac{Ƹ(X-x̅)^2}{n-1} = \frac{16.403}{10-1}\)

=\(\frac{16.403}{9}\)

=1823

Bulk culture-

The sum of values in the (X-x̅)^2 column = Ƹ(X-x̅)^2 = 80

Since there are 10 samples in this data set, n=10. Placing these values into the formula for calculating the variance yields,

Variance = \(\frac{Ƹ(X-x̅)^2}{n-1} = \frac{80}{10-1}\)

= \(\frac{80}{9}\)

= 8.9

Correct answer is (a) True

The explanation: Place the GRADUATED cylinder on a flat surface and view the height of the liquid in the cylinder with your eyes directly level with the liquid. The liquid will TEND to curve DOWNWARD. This curve is called the meniscus. Always read the MEASUREMENT at the BOTTOM of the meniscus.

Right option is (a) Exponential GROWTH Phase

For explanation I would say: The Log/ Exponential Growth phase is a period characterized by cell doubling. If growth is not limited, doubling will continue at a constant rate so both the number of CELLS and the rate of population increase doubles with each consecutive TIME period. For this type of exponential growth, plotting the natural logarithm of cell number against time produces a STRAIGHT LINE.

Correct answer is (C) To change a number to its nearest whole number

For explanation: To reduce successively the number of digits to the RIGHT of the decimal point of a MIXED number by dropping the final DIGIT and adding 1 to the next preceding digit if the dropped digit was 5 or GREATER, or leaving the preceding digit unchanged if the dropped digit was 4 or less.

Right OPTION is (b) Convex meniscus

Easiest EXPLANATION: A convex meniscus occurs when the molecules have a stronger ATTRACTION to each other than to the container and Mercury does not wet GLASS – the COHESIVE forces within the drops i.e., bond between the molecules of mercury are stronger than the adhesive forces between the drops and glass.

Correct answer is (a) Continuous- Scatter plot/LINE, Clumped- Histogram

Explanation: HISTOGRAM :

Histograms are similar to bar graphs except the data represented in histogram is usually in groups of continuous numerical (quantitative) data. In this case, the bars do touch. Histograms are often used to show FREQUENCY data.

Example- Average MEAN temperature between the years 1900 and 2000

SCATTER- PLOT:

The points are plotted on the grid, but they are not JOINED point to point. A best fit line may be added to a scatter plot to show a trend. Line graphs are only used when both variables are quantitative. These graphs are useful for showing if a CORRELATION exists between two variables, especially when it is not possible to alter either of the variables (i.e. in descriptive studies).

Example – Reaction rate at various enzyme concentrations.

Correct answer is (a) True

The explanation is: A straight LINE on log-log graph paper corresponds to the equation:

Y = Bx^A

In y = In B + A In x

If A is positive, y = 0 when x = 0, If A is negative, when x = 0, y is infinite;

If the log-log graph paper is drawn so that the ordinate and abscissa scales are the same, i.e. the distance MEASURED with a ruler for a 10-fold CHANGE in the y variable is the same as for a 10-fold change in the x variable, A is the actual slope of the line. A is obtained by TAKING two points (X1, Y1) and (X2, Y2) on the line, and measuring the distances between Y2 and Y1 and X2 and X1 with a ruler:

Correct option is (b) Scatter plot

For explanation I would say: A line of BEST fit (or “trend” line) is a straight line that best represents the data on a scatter plot. This line may pass through some of the POINTS, NONE of the points, or all of the points.

Correct option is (d) 2%

Easy explanation: Experimental value = 8.78 g/cm^3

Accepted value = 8.96 g/cm^3

STEP 1: Subtract the accepted value from the experimental value.

8.78 g/cm^3 – 8.96 g/cm^3 = -0.18 g/cm^3

Step 2: Take the absolute value of step 1

|-0.18 g/cm^3| = 0.18 g/cm^3

Step 3: Divide that answer by the accepted value, 0.18g/cm^3 ÷ 8.96g/cm^3 = 0.02

Step 4: Multiply that answer by 100 and ADD the % symbol to express the answer as a percentage.

0.02 x 100 = 2

The percent error of your DENSITY CALCULATION was 2%.

Right choice is (B) 425.7, 425.68, 430

Explanation: In the Tenths (1 decimal place), we will take 68 as a digit after the decimal and ROUND off it to the multiple of ten as 70, In the hundredths (2 decimal place), we will take both 68 as a number afterthe decimal because we have to take 2 decimal places and 6,8 both NUMBERS are greater than 5, In the TENS place, we will round the number before the decimal place to the closest multiple of ten, i.e. 430.

The correct choice is (c) (If the POPULATION is growing exponentially, you will SEE a STRAIGHT line), (If the growth is slower than exponential, the curve will be concave down), (If the growth is faster than exponential, the curve will be concave up)

Easy explanation: Functions plotted on the linear scale:

Figure 1:

Figure 2:

Functions plotted on the log-linear graph:

Figure 3 :

Figure 4 :

From the above graphs mentioned, Figures 2 and 4 GROWS exponentially while the function in Figures 1 and 3 grows slower than exponentially since the curve is concave down.

Correct OPTION is (a) (0.118 hours, 5.9 hours)

To explain: The regression results show that μ = 0.118 hr^-1. The DOUBLING time,

TD = ln(2)/μ

= 0.693/0.118

= 5.9 hrs.

The correct option is (c) 0.003gm,0.02%

EXPLANATION: RANGE = (14.568 – 14.565) g = 0.003 g,

This is a reasonable range; the uncertainty appears in the last significant FIGURE of the measured value, as it should.

The average value for the mass of the object is 14.566 g. Therefore:

% of average = (0.003 g/14.566 g) x 100% = 0.02%

the range as a percent of average (RPA) has only one significant figure in this case because the numerator of the fraction has only one.

Right CHOICE is (b) Molarity will CHANGE but not Molality

The explanation: Molarity is the number of moles of solute per kilogram of the Solvent. That is because molarity does not depend on temperature, (neither on number of moles of solute nor MASS of solvent will be AFFECTED by changes of temperature). While molarity changes as temperature changes because molarity is affected by temperature. This is because it is BASED on the volume of the solution, and the volume of a substance will be affected by changes in temperature.

Right answer is (c) 2.43%

To explain: Given:

True value = 123cms

Measured value = 120cms

Firstly, let us find out the ABSOLUTE ERROR.

We know by subtracting true value with measured value we GET absolute error = 123 – 120 = 3cms

THEREFORE, absolute error = 3cms

Now, let us find out the relative error = absolute error/True value x 100

= 3/123 x 100 = 2.43%

Therefore, the relative error for the given values = 2.43%.

Right option is (B) 600NM

The explanation: 600nm is a WAVELENGTH of light that is minimally absorbed by material within cells. Therefore, they can be more reliably used than other wavelengths (in most common situations). To SIMPLY, measure the scattering of light due to turbidity (just general presence of PARTICLES in a solution).

Correct answer is (c) Scatter plot

The EXPLANATION: A line of best FIT is a STRAIGHT line drawn through the center of a group of data points plotted on a scatter plot. Scatter plots depict the results of gathering data on two variables. The line of best fit shows whether these two variables appear to be correlated and can be used to help identify trends occurring within the dataset. ANALYSTS may use the line of best fit when determining a relationship between two variables where one variable is INDEPENDENT and one variable is being examined for dependency.

The correct option is (a) Monod equation

The explanation: Jacques Monod discovered diauxic growth in 1941 during his EXPERIMENTS with Escherichia coli and BACILLUS subtilis. While growing these bacteria on various combinations of sugars during his doctoral thesis RESEARCH, Monod OBSERVED that often two distinct growth phases are CLEARLY visible in batch culture.

Right choice is (a) Representation of the asexual reproduction of the bacteria

The explanation: The representation is of the Bacterial growth which is the asexual reproduction, or cell division, of a bacterium into two daughter CELLS, in a process called binary FISSION. PROVIDING no mutational event occurs, the RESULTING daughter cells are GENETICALLY identical to the original cell.

Correct answer is (a) -1.5%

To ELABORATE: % DIFFERENCE = [(19.03 – 19.31) G/19.31 g] x 100% = – 1.5%

A percent difference can be POSITIVE or negative; the sign shows whether the experimental value is HIGHER or lower than the actual or theoretical value. This distinction is not used in precision since all values are experimental.

Right option is (b) Non- LINEAR regression analysis or general regression analysis

The explanation is: If the growth rates fit a POLYNOMIAL CURVE, you can use General Regression and enter the bacteria type as categorical variable. Otherwise, you may need to use NONLINEAR regression SEPARATELY for each type.

The correct option is (d) Comparison between multivariate samples

To explain I would say: In statistics, multivariate analysis of variance (MANOVA) is a procedure for COMPARING multivariate SAMPLE means. As a multivariate procedure, it is USED when there are TWO or more dependent variables and is typically followed by significance tests involving INDIVIDUAL dependent variables separately.

Correct option is (d) 1- cycle semi LOGARITHMIC paper

For EXPLANATION I would say: In one-cycle semi-logarithmic paper, the vertical SCALE goes from 1 to 10 and within the One order of magnitude (10^1) whereas, in others the magnitude varies like in 2 – cycle there is the magnitude of two i.e. (10^2) and likewise other options have different magnitudes according to their number of cycles.