Plasmid is a:a)Extra chromosomal DNA in bacterial cellb)Fungusc)Plastidd)Part of plasma membraneCorrect answer is option 'A'. Can you explain this answer?

Question

Answer

A plasmid is an extra-chromosomal element, often a circular DNA molecule found in bacteria and other cells. The plasmids have three important elements i.e., an origin of replication, a selectable marker gene, and a cloning site. They are most commonly found in bacteria as small, circular, double-stranded DNA molecules and having the capability of autonomous replication within the host cell. So, the correct answer is option A.

Answer

Plasmid is a small extra chromosomal DNA inside prokaryotes like bacterial cells.It is used as a vector in biotechnology.It offers antibiotic resistance to the bacterial cell also.hope it helps

Answer

Plasmid is a double stranded extra circular chromosomal DNA found in bacteria , plasmid is used as a vector/ vehicle for replication of desired gene in production of medicine (human insulin) . Plasmid is transferred to bacteria and production of medicine for expression we need bioreactor . Bioreactor are in two types 1) simple strried bioreactor (curved shape) 2) sparged stirred bioreactor ( corner are present ) (stirred: for involved oxygen )

Answer

Plasmid is Extra chromosomal DNA in bacterial cell

Extra chromosomal DNA in bacterial cell

Plasmids are small, circular, double-stranded DNA molecules that exist separately from the bacterial chromosome. They are commonly found in bacteria and some other organisms like yeast. Plasmids are not essential for the survival of the bacteria, but they can provide additional advantages to the host cell.

Characteristics of plasmids:

1. Circular DNA: Plasmids are circular DNA molecules, which means they have no ends. This circular structure allows plasmids to replicate independently from the bacterial chromosome.

2. Small size: Plasmids are relatively small compared to the bacterial chromosome. They can range in size from a few thousand to a few hundred thousand base pairs.

3. Extra chromosomal: Plasmids exist separately from the bacterial chromosome. They can be present in multiple copies within a single bacterial cell.

Functions of plasmids:

1. Antibiotic resistance: Some plasmids carry genes that provide resistance to antibiotics. These genes can be transferred between bacteria through horizontal gene transfer, allowing the spread of antibiotic resistance.

2. Virulence factors: Certain plasmids carry genes that encode virulence factors, which are molecules that help bacteria cause disease. These plasmids can enhance the pathogenicity of the bacteria.

3. Metabolic capabilities: Plasmids can carry genes that encode enzymes involved in specific metabolic pathways. These plasmids allow bacteria to metabolize certain substances that they otherwise would not be able to.

4. Conjugation: Plasmids can contain genes that enable bacterial conjugation, a mechanism of horizontal gene transfer. Conjugation allows the transfer of plasmids between bacteria, leading to the spread of genetic information.

Importance of plasmids:

Plasmids play a crucial role in bacterial adaptation and evolution. They provide bacteria with the ability to rapidly acquire new genes and traits, allowing them to survive and thrive in various environments. Plasmids also contribute to the spread of antibiotic resistance, which is a major concern in healthcare settings.

In conclusion, plasmids are extra chromosomal DNA molecules found in bacterial cells. They carry genes that provide advantages to the host cell such as antibiotic resistance, virulence factors, and metabolic capabilities. Plasmids are important for bacterial adaptation and evolution and contribute to the spread of antibiotic resistance.

Answer

Plasmid is a:
Plasmid is an extra chromosomal DNA in bacterial cells. It is a small, circular, double-stranded DNA molecule that is separate from the bacterial chromosome. Here are the reasons why plasmid is considered as an extra chromosomal DNA in bacterial cells:
1. Definition:
- Plasmid is a self-replicating genetic structure found in the cytoplasm of bacterial cells.
- It is not an essential part of the bacterial genome, but it can be beneficial for the bacterial cell under certain conditions.
2. Characteristics:
- Plasmids are small in size, typically ranging from 1 to 100 kilobase pairs (kb) in length.
- They are circular in shape, although some plasmids can be linear.
- Plasmids can exist in multiple copies within a bacterial cell.
3. Replication and Inheritance:
- Plasmids replicate independently of the bacterial chromosome.
- During cell division, plasmids are partitioned equally between the daughter cells.
- Plasmids can be transferred between bacterial cells through a process called conjugation.
4. Functions:
- Plasmids often carry genes that provide advantages to the bacterial cell, such as antibiotic resistance, toxin production, or the ability to utilize specific nutrients.
- These genes are not essential for the survival of the bacterial cell but can enhance its fitness in certain environments.
- Plasmids can also serve as vectors for genetic engineering purposes, allowing the introduction of foreign DNA into bacterial cells.
5. Importance:
- Plasmids play a crucial role in bacterial evolution and adaptation.
- They can confer selective advantages to bacterial populations and contribute to the spread of antibiotic resistance genes.
- Plasmids can also facilitate the horizontal transfer of genetic material between different bacterial species.
In conclusion, plasmids are extra chromosomal DNA in bacterial cells. They are small, circular, self-replicating genetic structures that carry non-essential but advantageous genes. Plasmids contribute to bacterial evolution, adaptation, and the spread of antibiotic resistance.

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