The unicellular green alga Chlorella is often used as a model organism to study the effects of various substances on the growth of photosynthetic organisms. Researchers studying the detoxification of certain metals by Chlorella first collected data on the growth dynamics of the alga. A small number of Chlorella were added to 1,500 mL of culture medium that contained all of the inorganic nutrients needed for growth. Every five days for 30 days, the researchers performed multiple counts to determine the concentration of Chlorella in the culture.
a. Describe why the amount of light available to the Chlorella culture might affect the growth dynamics of the alga.
b. Using the template, construct an appropriately labeled graph to represent the data in Table 1. Based on the data, determine whether the concentration of Chlorella on day 20 is statistically different from the concentration on day 15 and from the concentration on day 25.
c. Based on the data, describe the time period during which Chlorella approximates exponential growth. Based on the data and assuming logistic growth, describe the time period during which the Chlorella population has reached the carrying capacity of the culture. Based on the data, calculate the growth rate per day for the five-day period with the greatest growth rate
d. If the Chlorella culture is maintained for an additional 120 days, predict the most likely effect on the number of cells counted every five days. Provide reasoning to justify your prediction.
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The unicellular green alga Chlorella is often used as a model organism to study the effects of various substances on the growth of photosynthetic organisms. Researchers studying the detoxification of certain metals by Chlorella first collected data on the growth dynamics of the alga. A small number of Chlorella were added to 1,500 mL of culture medium that contained all of the inorganic nutrients needed for growth. Every five days for 30 days, the researchers performed multiple counts to determine the concentration of Chlorella in the culture.
a. Describe why the amount of light available to the Chlorella culture might affect the growth dynamics of the alga.
b. Using the template, construct an appropriately labeled graph to represent the data in Table 1. Based on the data, determine whether the concentration of Chlorella on day 20 is statistically different from the concentration on day 15 and from the concentration on day 25.
c. Based on the data, describe the time period during which Chlorella approximates exponential growth. Based on the data and assuming logistic growth, describe the time period during which the Chlorella population has reached the carrying capacity of the culture. Based on the data, calculate the growth rate per day for the five-day period with the greatest growth rate
d. If the Chlorella culture is maintained for an additional 120 days, predict the most likely effect on the number of cells counted every five days. Provide reasoning to justify your prediction.