Chapter 7.L2, Problem 1CT

1. a. Is there a microbe that could grow on a medium that contains only the following compounds dissolved in water: CaC03, MgN03, FeCl2,ZnS04, and glucose? Defend your answer.

b. A useful mnemonic device for keeping track of major elements required by most organisms is: C HOPKINS Ca Fe, Na Cl M good. Read aloud, it becomes “See Hopkin’s Cafe, NaCl (salt) M good!� What does each letter stand for?

Summary Introduction

To determine:

1. If any microbe can grow in a medium containing only CaCO₃, MgNO₃, FeCl₂, ZnSO₄ and glucose dissolved in water.
2. The representation of each letter in C HOPKINS Ca Fe, Na Cl Mgood.

Introduction:

There are some basic components (elements) that are required for microbes to grow. This can easily be determined by the phrase in C HOPKINS Ca Fe, Na Cl Mgood.

Explanation of Solution

1. Since there is no source of phosphorous in the given solution this combination may not be helpful for any microbe to grow. Phosphorus is needed for synthesis of the nucleic acids, that is the genetic material of any organism.
2. C HOPKINS Ca Fe, Na Cl Mgood is a mnemonic phrase that helps in determining the minimum required elements for life to grow. These are a list of essential nutrients. In this phrase there is a specific representation for each alphabet, which are as follows:

C: carbon

H: hydrogen

O: oxygen

P: phosphorus

K: potassium

I: iodine

N: nitrogen

S: sulfur

Ca: calcium

Fe: iron

Na: sodium

Cl: chlorine

Mg: magnesium

Conclusion

Hence, it may be concluded that, there are some specific elements that are required by all organisms to grow and this may be determined by the mnemonic in C HOPKINS Ca Fe, Na Cl Mgood.