Ch. 2 - Chemical Principles

Tortora - Microbiology: An Introduction 14th Edition

Tortora14th EditionMicrobiology: An IntroductionISBN: 9780138200398Non è quello che usi tu?Cambia libro di testo

Tortora 14th Edition

Ch. 2 - Chemical Principles

Problema 3

Capitolo 2, Problema 3

Radioisotopes are frequently used to label molecules in a cell. The fate of atoms and molecules in a cell can then be followed. This process is the basis for the following question.

If E. coli were grown in a medium containing the radioactive isotope ³²P, the ³²P would be found in all of the following molecules of the cell except
a. ATP.
b. Carbohydrates.
c. DNA.
d. Plasma membrane.
e. Complex lipids.

Guida verificata passo dopo passo

Understand that the radioactive isotope ³²P (phosphorus-32) is incorporated into molecules that contain phosphorus atoms within the cell.

Identify which cellular molecules naturally contain phosphorus. For example, ATP contains phosphate groups, DNA contains a sugar-phosphate backbone, and complex lipids like phospholipids have phosphate groups in their structure.

Recognize that carbohydrates generally do not contain phosphorus atoms in their basic structure, so they would not incorporate ³²P.

Consider the plasma membrane composition: it includes phospholipids (which contain phosphorus), so ³²P would be found there as well.

Conclude that the molecule type that does not contain phosphorus and therefore would not be labeled with ³²P is carbohydrates.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Radioisotope Labeling in Cells

Radioisotope labeling involves incorporating radioactive atoms into molecules to trace their path and fate within cells. By using isotopes like ³²P, scientists can track molecules containing specific elements, helping to study cellular processes such as metabolism and molecular synthesis.

Video consigliato:

05:33

Cell Junctions

Phosphorus in Cellular Molecules

Phosphorus is a key element found in molecules like nucleic acids (DNA, RNA), ATP, and phospholipids of the plasma membrane. It is typically absent in carbohydrates, which mainly contain carbon, hydrogen, and oxygen, making phosphorus a useful marker for identifying certain biomolecules.

Video consigliato:

02:58

Adhesion Molecules

Molecular Composition of Cell Components

Understanding the chemical makeup of cellular components is essential. ATP contains phosphate groups, DNA has a phosphate backbone, plasma membranes include phospholipids, and complex lipids often contain phosphorus. Carbohydrates, however, generally lack phosphorus, distinguishing them from these other molecules.

Video consigliato:

03:20

The 3 Molecular Koch's Postulates

Pratica correlata

Domanda del libro di testo

Radioisotopes are frequently used to label molecules in a cell. The fate of atoms and molecules in a cell can then be followed. This process is the basis for the following question.

If Pseudomonas bacteria are supplied with radioactively labeled cytosine, after a 24-hour incubation period this cytosine would most likely be found in the cells’

a. Carbohydrates.

b. DNA.

c. Lipids.

d. Water.

e. Proteins.

788

views

Domanda del libro di testo

What type of bond holds the following atoms together?

a. Li⁺ and Cl^- in LiCl

b. Carbon and oxygen atoms in methanol

c. Oxygen atoms in O₂