Question

Gene transfer in which a bacterial cell takes up bacterial DNA from the environment is called a. conjugation. b. binary fission. c. ascrual reproduction. d. transformation. e. transduction.

Short answer

The correct answer is d. transformation.

Step-by-step solution

Recall the processes

Remember the definitions of the gene transfer processes. Conjugation is the direct transfer of genetic material from one bacterial cell to another. Binary fission is a method of asexual reproduction in single-celled organisms like bacteria. Ascrual reproduction does not exist, it seems to be a typographic error or perhaps an intentional distractor in the options. Transformation is the gene transfer method where bacteria take up genetic material from the environment. Transduction is the process where bacteriophages (viruses that infect bacteria) carry bacterial DNA from one bacterium to another.

Choose the correct process

Based on our recall of different processes, the correct answer would be the process in which a bacteria take up genetic material from its surroundings. This process is known as transformation.

Key concepts

Gene Transfer in Bacteria

Gene transfer in bacteria is an essential process that provides genetic diversity and adaptation to changing environments. It involves the movement of genetic information between bacterial cells, and there are different mechanisms through which this can occur.

The hallmark of bacterial gene transfer is its role in allowing bacteria to share advantageous traits, such as antibiotic resistance or metabolic capabilities. This sharing can happen through processes including transformation, conjugation, and transduction, each with unique characteristics and implications for bacterial evolution and medical challenges like the proliferation of resistance to antibiotics.

Understanding these mechanisms is crucial because it informs antibiotic use policies, development of new treatments, and strategies to combat bacterial infections.

Conjugation

Conjugation is the direct transfer of DNA from one bacterial cell to another through a physical connection called a pilus. Think of it as a microscopic handshake where one cell passes a piece of genetic material to its neighbor.

This process is typically initiated by a donor cell, which carries a piece of circular DNA called a plasmid. The plasmid often contains genes that can be beneficial for survival, like those conferring antibiotic resistance. Once the pilus forms a bridge between two cells, the plasmid can be copied and transferred to the recipient cell, potentially enabling it to thrive in environments it previously could not.

Binary Fission

Binary fission is a form of asexual reproduction and is the primary method through which bacteria multiply. In this process, a single bacterial cell divides into two identical daughter cells.

During binary fission, the bacterium's DNA is replicated, and the cell grows in size until it splits, distributing a copy of the DNA to each new cell. This method ensures rapid population growth. While binary fission doesn't introduce genetic diversity by itself, it's important to note that mutations can occur during DNA replication, which may lead to variations among the bacterial offspring.

Transduction

Transduction is a fascinating form of gene transfer, where a bacteriophage, a virus that infects bacteria, inadvertently shuttles DNA from one bacterium to another.

During this process, a bacteriophage injects its own genetic material into a bacterial cell, hijacking the cell's machinery to produce new virus particles. Occasionally, a mistake occurs, and bacterial DNA is packed into the new viruses. When these viruses infect another bacterium, they can inject the DNA cargo they are carrying, leading to a genetic swap. This accidental gene transfer can have significant evolutionary implications for bacteria, allowing them to acquire new traits from unrelated bacterial strains.