# data[].attributes.body
the transplantation of normal genes into cells in place of missing or defective ones in order to correct genetic disorders.

# data[].attributes.body
When an organism has an extra set of chromosomes, which is deadly to animals but plants can be polyploidy and survive.

# data[].attributes.body
a class of regulatory genes that determine the identity of body parts and regions in an animal embryo. Mutations in these genes can transform one body part into another.

# data[].attributes.body
single-stranded nucleic acid that contains the sugar ribose.

# data[].attributes.attachment_link.readable_text
PCR is a technique used in the lab to make millions of copies of a particular section of DNA. It was first developed in the 1980s.

What is PCR?

The polymerase chain reaction (PCR) was originally developed in 1983 by the American biochemist Kary Mullis. He was awarded the Nobel Prize in Chemistry in 1993 for his pioneering work.

PCR is used in molecular biology to make many copies of (amplify) small sections of DNA or a gene.

Using PCR it is possible to generate thousands to millions of copies of a particular section of DNA from a very small amount of DNA.

PCR is a common tool used in medical and biological research labs. It is used in the early stages of processing DNA for sequencing, for detecting the presence or absence of a gene to help identify pathogens during infection, and when generating forensic DNA profiles from tiny samples of DNA.

How does PCR work?

The principles behind every PCR, whatever the sample of DNA, are the same.

Five core 'ingredients' are required to set up a PCR. We will explain exactly what each of these do as we go along. These are:

the DNA template to be copied

primers, short stretches of DNA that initiate the PCR reaction, designed to bind to either side of the section of DNA you want to copy

DNA nucleotide bases (also known as dNTPs). DNA bases (A, C, G and T) are the building blocks of DNA and are needed to construct the new strand of DNA

Taq polymerase enzyme to add in the new DNA bases

buffer to ensure the right conditions for the reaction.

PCR involves a process of heating and cooling called thermal cycling which is carried out by machine.

There are three main stages:

1. Denaturing - when the double-stranded template DNA is heated to separate it into two single strands.

2. Annealing - when the temperature is lowered to enable the DNA primers to attach to the template DNA.

3. Extending - when the temperature is raised and the new strand of DNA is made by the Taq polymerase enzyme.

These three stages are repeated 20-40 times, doubling the number of DNA copies each time.

A complete PCR reaction can be performed in a few hours, or even less than an hour with certain high-speed machines.

After PCR has been completed, a method called electrophoresis can be used to check the quantity and size of the DNA fragments produced.

What happens at each stage of PCR?

Denaturing stage

During this stage the cocktail containing the template DNA and all the other core ingredients is heated to 94-95⁰C.

The high temperature causes the hydrogen bonds between the bases in two strands of template DNA to break and the two strands to separate.

This results in two single strands of DNA, which will act as templates for the production of the new strands of DNA.

It is important that the temperature is maintained at this stage for long enough to ensure that the DNA strands have separated completely.

This usually takes between 15-30 seconds.

Annealing stage

During this stage the reaction is cooled to 50-65⁰C. This enables the primers to attach to a specific location on the single-stranded template DNA by way of hydrogen bonding (the exact temperature depends on the melting temperature of the primers you are using).

Primers are single strands of DNA or RNA sequence that are around 20 to 30 bases in length.

The primers are designed to be complementary in sequence to short sections of DNA on each end of the sequence to be copied.

Primers serve as the starting point for DNA synthesis. The polymerase enzyme can only add DNA bases to a double strand of DNA. Only once the primer has bound can the polymerase enzyme attach and start making the new complementary strand of DNA from the loose DNA bases.

The two separated strands of DNA are complementary and run in opposite directions (from one end - the 5' end - to the other - the 3' end); as a result, there are two primers - a forward primer and a reverse primer.

This step usually takes about 10-30 seconds.

Extending stage

During this final step, the heat is increased to 72⁰C to enable the new DNA to be made by a special Taq DNA polymerase enzyme which adds DNA bases.

Taq DNA polymerase is an enzyme taken from the heat-loving bacteria Thermus aquaticus.

This bacteria normally lives in hot springs so can tolerate temperatures above 80⁰C.

The bacteria's DNA polymerase is very stable at high temperatures, which means it can withstand the temperatures needed to break the strands of DNA apart in the denaturing stage of PCR.

DNA polymerase from most other organisms would not be able to withstand these high temperatures, for example, human polymerase works ideally at 37˚C (body temperature).

72⁰C is the optimum temperature for the Taq polymerase to build the complementary strand. It attaches to the primer and then adds DNA bases to the single strand one-by-one in the 5' to 3' direction.

The result is a brand new strand of DNA and a double-stranded molecule of DNA.

The duration of this step depends on the length of DNA sequence being amplified but usually takes around one minute to copy 1,000 DNA bases (1Kb).

These three processes of thermal cycling are repeated 20-40 times to produce lots of copies of the DNA sequence of interest.

The new fragments of DNA that are made during PCR also serve as templates to which the DNA polymerase enzyme can attach and start making DNA.

The result is a huge number of copies of the specific DNA segment produced in a relatively short period of time.

# data[].attributes.attachment_link.title
What is PCR (polymerase chain reaction)?

# data[].attributes.attachment_link.description
PCR is a technique used in the lab to make millions of copies of a particular section of DNA. It was first developed in the 1980s. The polymerase chain reaction (PCR) was originally developed in 1983 by the American biochemist Kary Mullis. He was awarded the Nobel Prize in Chemistry in 1993 for his pioneering work.

# data[].attributes.attachment_link.readable_text
PCR is a technique used in the lab to make millions of copies of a particular section of DNA. It was first developed in the 1980s.

What is PCR?

The polymerase chain reaction (PCR) was originally developed in 1983 by the American biochemist Kary Mullis. He was awarded the Nobel Prize in Chemistry in 1993 for his pioneering work.

PCR is used in molecular biology to make many copies of (amplify) small sections of DNA or a gene.

Using PCR it is possible to generate thousands to millions of copies of a particular section of DNA from a very small amount of DNA.

PCR is a common tool used in medical and biological research labs. It is used in the early stages of processing DNA for sequencing, for detecting the presence or absence of a gene to help identify pathogens during infection, and when generating forensic DNA profiles from tiny samples of DNA.

How does PCR work?

The principles behind every PCR, whatever the sample of DNA, are the same.

Five core 'ingredients' are required to set up a PCR. We will explain exactly what each of these do as we go along. These are:

the DNA template to be copied

primers, short stretches of DNA that initiate the PCR reaction, designed to bind to either side of the section of DNA you want to copy

DNA nucleotide bases (also known as dNTPs). DNA bases (A, C, G and T) are the building blocks of DNA and are needed to construct the new strand of DNA

Taq polymerase enzyme to add in the new DNA bases

buffer to ensure the right conditions for the reaction.

PCR involves a process of heating and cooling called thermal cycling which is carried out by machine.

There are three main stages:

1. Denaturing - when the double-stranded template DNA is heated to separate it into two single strands.

2. Annealing - when the temperature is lowered to enable the DNA primers to attach to the template DNA.

3. Extending - when the temperature is raised and the new strand of DNA is made by the Taq polymerase enzyme.

These three stages are repeated 20-40 times, doubling the number of DNA copies each time.

A complete PCR reaction can be performed in a few hours, or even less than an hour with certain high-speed machines.

After PCR has been completed, a method called electrophoresis can be used to check the quantity and size of the DNA fragments produced.

What happens at each stage of PCR?

Denaturing stage

During this stage the cocktail containing the template DNA and all the other core ingredients is heated to 94-95⁰C.

The high temperature causes the hydrogen bonds between the bases in two strands of template DNA to break and the two strands to separate.

This results in two single strands of DNA, which will act as templates for the production of the new strands of DNA.

It is important that the temperature is maintained at this stage for long enough to ensure that the DNA strands have separated completely.

This usually takes between 15-30 seconds.

Annealing stage

During this stage the reaction is cooled to 50-65⁰C. This enables the primers to attach to a specific location on the single-stranded template DNA by way of hydrogen bonding (the exact temperature depends on the melting temperature of the primers you are using).

Primers are single strands of DNA or RNA sequence that are around 20 to 30 bases in length.

The primers are designed to be complementary in sequence to short sections of DNA on each end of the sequence to be copied.

Primers serve as the starting point for DNA synthesis. The polymerase enzyme can only add DNA bases to a double strand of DNA. Only once the primer has bound can the polymerase enzyme attach and start making the new complementary strand of DNA from the loose DNA bases.

The two separated strands of DNA are complementary and run in opposite directions (from one end - the 5' end - to the other - the 3' end); as a result, there are two primers - a forward primer and a reverse primer.

This step usually takes about 10-30 seconds.

Extending stage

During this final step, the heat is increased to 72⁰C to enable the new DNA to be made by a special Taq DNA polymerase enzyme which adds DNA bases.

Taq DNA polymerase is an enzyme taken from the heat-loving bacteria Thermus aquaticus.

This bacteria normally lives in hot springs so can tolerate temperatures above 80⁰C.

The bacteria's DNA polymerase is very stable at high temperatures, which means it can withstand the temperatures needed to break the strands of DNA apart in the denaturing stage of PCR.

DNA polymerase from most other organisms would not be able to withstand these high temperatures, for example, human polymerase works ideally at 37˚C (body temperature).

72⁰C is the optimum temperature for the Taq polymerase to build the complementary strand. It attaches to the primer and then adds DNA bases to the single strand one-by-one in the 5' to 3' direction.

The result is a brand new strand of DNA and a double-stranded molecule of DNA.

The duration of this step depends on the length of DNA sequence being amplified but usually takes around one minute to copy 1,000 DNA bases (1Kb).

These three processes of thermal cycling are repeated 20-40 times to produce lots of copies of the DNA sequence of interest.

The new fragments of DNA that are made during PCR also serve as templates to which the DNA polymerase enzyme can attach and start making DNA.

The result is a huge number of copies of the specific DNA segment produced in a relatively short period of time.

# data[].attributes.attachment_link.title
What is PCR (polymerase chain reaction)?

# data[].attributes.attachment_link.description
PCR is a technique used in the lab to make millions of copies of a particular section of DNA. It was first developed in the 1980s. The polymerase chain reaction (PCR) was originally developed in 1983 by the American biochemist Kary Mullis. He was awarded the Nobel Prize in Chemistry in 1993 for his pioneering work.

# data[].attributes.body
Transgenic Bacteria are grown in large vats where they can make products such as insulin and human grown hormone, and vaccines.

# data[].attributes.body
Molecule of DNA that has been formed artificially containing DNA from 2 different organisms

# data[].attributes.attachment_link.readable_text
PCR is a technique used in the lab to make millions of copies of a particular section of DNA. It was first developed in the 1980s.

What is PCR?

The polymerase chain reaction (PCR) was originally developed in 1983 by the American biochemist Kary Mullis. He was awarded the Nobel Prize in Chemistry in 1993 for his pioneering work.

PCR is used in molecular biology to make many copies of (amplify) small sections of DNA or a gene.

Using PCR it is possible to generate thousands to millions of copies of a particular section of DNA from a very small amount of DNA.

PCR is a common tool used in medical and biological research labs. It is used in the early stages of processing DNA for sequencing, for detecting the presence or absence of a gene to help identify pathogens during infection, and when generating forensic DNA profiles from tiny samples of DNA.

How does PCR work?

The principles behind every PCR, whatever the sample of DNA, are the same.

Five core 'ingredients' are required to set up a PCR. We will explain exactly what each of these do as we go along. These are:

the DNA template to be copied

primers, short stretches of DNA that initiate the PCR reaction, designed to bind to either side of the section of DNA you want to copy

DNA nucleotide bases (also known as dNTPs). DNA bases (A, C, G and T) are the building blocks of DNA and are needed to construct the new strand of DNA

Taq polymerase enzyme to add in the new DNA bases

buffer to ensure the right conditions for the reaction.

PCR involves a process of heating and cooling called thermal cycling which is carried out by machine.

There are three main stages:

1. Denaturing - when the double-stranded template DNA is heated to separate it into two single strands.

2. Annealing - when the temperature is lowered to enable the DNA primers to attach to the template DNA.

3. Extending - when the temperature is raised and the new strand of DNA is made by the Taq polymerase enzyme.

These three stages are repeated 20-40 times, doubling the number of DNA copies each time.

A complete PCR reaction can be performed in a few hours, or even less than an hour with certain high-speed machines.

After PCR has been completed, a method called electrophoresis can be used to check the quantity and size of the DNA fragments produced.

What happens at each stage of PCR?

Denaturing stage

During this stage the cocktail containing the template DNA and all the other core ingredients is heated to 94-95⁰C.

The high temperature causes the hydrogen bonds between the bases in two strands of template DNA to break and the two strands to separate.

This results in two single strands of DNA, which will act as templates for the production of the new strands of DNA.

It is important that the temperature is maintained at this stage for long enough to ensure that the DNA strands have separated completely.

This usually takes between 15-30 seconds.

Annealing stage

During this stage the reaction is cooled to 50-65⁰C. This enables the primers to attach to a specific location on the single-stranded template DNA by way of hydrogen bonding (the exact temperature depends on the melting temperature of the primers you are using).

Primers are single strands of DNA or RNA sequence that are around 20 to 30 bases in length.

The primers are designed to be complementary in sequence to short sections of DNA on each end of the sequence to be copied.

Primers serve as the starting point for DNA synthesis. The polymerase enzyme can only add DNA bases to a double strand of DNA. Only once the primer has bound can the polymerase enzyme attach and start making the new complementary strand of DNA from the loose DNA bases.

The two separated strands of DNA are complementary and run in opposite directions (from one end - the 5' end - to the other - the 3' end); as a result, there are two primers - a forward primer and a reverse primer.

This step usually takes about 10-30 seconds.

Extending stage

During this final step, the heat is increased to 72⁰C to enable the new DNA to be made by a special Taq DNA polymerase enzyme which adds DNA bases.

Taq DNA polymerase is an enzyme taken from the heat-loving bacteria Thermus aquaticus.

This bacteria normally lives in hot springs so can tolerate temperatures above 80⁰C.

The bacteria's DNA polymerase is very stable at high temperatures, which means it can withstand the temperatures needed to break the strands of DNA apart in the denaturing stage of PCR.

DNA polymerase from most other organisms would not be able to withstand these high temperatures, for example, human polymerase works ideally at 37˚C (body temperature).

72⁰C is the optimum temperature for the Taq polymerase to build the complementary strand. It attaches to the primer and then adds DNA bases to the single strand one-by-one in the 5' to 3' direction.

The result is a brand new strand of DNA and a double-stranded molecule of DNA.

The duration of this step depends on the length of DNA sequence being amplified but usually takes around one minute to copy 1,000 DNA bases (1Kb).

These three processes of thermal cycling are repeated 20-40 times to produce lots of copies of the DNA sequence of interest.

The new fragments of DNA that are made during PCR also serve as templates to which the DNA polymerase enzyme can attach and start making DNA.

The result is a huge number of copies of the specific DNA segment produced in a relatively short period of time.

# data[].attributes.attachment_link.title
What is PCR (polymerase chain reaction)?

# data[].attributes.attachment_link.description
PCR is a technique used in the lab to make millions of copies of a particular section of DNA. It was first developed in the 1980s. The polymerase chain reaction (PCR) was originally developed in 1983 by the American biochemist Kary Mullis. He was awarded the Nobel Prize in Chemistry in 1993 for his pioneering work.

# data[].attributes.body
organisms containing genes from another organism

# data[].attributes.body
Select Breeding is the breeding of organisms with desired traits, such as strong healthy racing horses or purebred dogs

# data[].attributes.body
is the process by which humans use animal and plant breeding to develop particular phenotypic traits. By choosing which animal or plant with desired characteristics  are allowed to produce the next generation.

# data[].attributes.body
- one way that DNA can be separated and analyzed
-  can locate and identify a specific gene out of thousands
- can be used to compare different gene compositions of different organismes

# data[].attributes.attachment_link.title
gel electrophoresis | Learn Science at Scitable

# data[].attributes.attachment_link.description
Gel electrophoresis is a laboratory method used to separate mixtures of DNA, RNA, or proteins according to their sizes

# data[].attributes.body
The 4 stages consist of Prophase, Metaphase, Anaphase, and Telephase

# data[].attributes.body
Gel electrophoresis is a laboratory method used to separate mixtures of DNA, RNA, or proteins according to molecular size. In gel electrophoresis, the molecules to be separated are pushed by an electrical field through a gel that contains small pores.

# data[].attributes.body
the use of DNA as a pharmaceutical agent to treat diseases

# data[].attributes.attachment_link.readable_text
PCR is a technique used in the lab to make millions of copies of a particular section of DNA. It was first developed in the 1980s.

What is PCR?

The polymerase chain reaction (PCR) was originally developed in 1983 by the American biochemist Kary Mullis. He was awarded the Nobel Prize in Chemistry in 1993 for his pioneering work.

PCR is used in molecular biology to make many copies of (amplify) small sections of DNA or a gene.

Using PCR it is possible to generate thousands to millions of copies of a particular section of DNA from a very small amount of DNA.

PCR is a common tool used in medical and biological research labs. It is used in the early stages of processing DNA for sequencing, for detecting the presence or absence of a gene to help identify pathogens during infection, and when generating forensic DNA profiles from tiny samples of DNA.

How does PCR work?

The principles behind every PCR, whatever the sample of DNA, are the same.

Five core 'ingredients' are required to set up a PCR. We will explain exactly what each of these do as we go along. These are:

the DNA template to be copied

primers, short stretches of DNA that initiate the PCR reaction, designed to bind to either side of the section of DNA you want to copy

DNA nucleotide bases (also known as dNTPs). DNA bases (A, C, G and T) are the building blocks of DNA and are needed to construct the new strand of DNA

Taq polymerase enzyme to add in the new DNA bases

buffer to ensure the right conditions for the reaction.

PCR involves a process of heating and cooling called thermal cycling which is carried out by machine.

There are three main stages:

1. Denaturing - when the double-stranded template DNA is heated to separate it into two single strands.

2. Annealing - when the temperature is lowered to enable the DNA primers to attach to the template DNA.

3. Extending - when the temperature is raised and the new strand of DNA is made by the Taq polymerase enzyme.

These three stages are repeated 20-40 times, doubling the number of DNA copies each time.

A complete PCR reaction can be performed in a few hours, or even less than an hour with certain high-speed machines.

After PCR has been completed, a method called electrophoresis can be used to check the quantity and size of the DNA fragments produced.

What happens at each stage of PCR?

Denaturing stage

During this stage the cocktail containing the template DNA and all the other core ingredients is heated to 94-95⁰C.

The high temperature causes the hydrogen bonds between the bases in two strands of template DNA to break and the two strands to separate.

This results in two single strands of DNA, which will act as templates for the production of the new strands of DNA.

It is important that the temperature is maintained at this stage for long enough to ensure that the DNA strands have separated completely.

This usually takes between 15-30 seconds.

Annealing stage

During this stage the reaction is cooled to 50-65⁰C. This enables the primers to attach to a specific location on the single-stranded template DNA by way of hydrogen bonding (the exact temperature depends on the melting temperature of the primers you are using).

Primers are single strands of DNA or RNA sequence that are around 20 to 30 bases in length.

The primers are designed to be complementary in sequence to short sections of DNA on each end of the sequence to be copied.

Primers serve as the starting point for DNA synthesis. The polymerase enzyme can only add DNA bases to a double strand of DNA. Only once the primer has bound can the polymerase enzyme attach and start making the new complementary strand of DNA from the loose DNA bases.

The two separated strands of DNA are complementary and run in opposite directions (from one end - the 5' end - to the other - the 3' end); as a result, there are two primers - a forward primer and a reverse primer.

This step usually takes about 10-30 seconds.

Extending stage

During this final step, the heat is increased to 72⁰C to enable the new DNA to be made by a special Taq DNA polymerase enzyme which adds DNA bases.

Taq DNA polymerase is an enzyme taken from the heat-loving bacteria Thermus aquaticus.

This bacteria normally lives in hot springs so can tolerate temperatures above 80⁰C.

The bacteria's DNA polymerase is very stable at high temperatures, which means it can withstand the temperatures needed to break the strands of DNA apart in the denaturing stage of PCR.

DNA polymerase from most other organisms would not be able to withstand these high temperatures, for example, human polymerase works ideally at 37˚C (body temperature).

72⁰C is the optimum temperature for the Taq polymerase to build the complementary strand. It attaches to the primer and then adds DNA bases to the single strand one-by-one in the 5' to 3' direction.

The result is a brand new strand of DNA and a double-stranded molecule of DNA.

The duration of this step depends on the length of DNA sequence being amplified but usually takes around one minute to copy 1,000 DNA bases (1Kb).

These three processes of thermal cycling are repeated 20-40 times to produce lots of copies of the DNA sequence of interest.

The new fragments of DNA that are made during PCR also serve as templates to which the DNA polymerase enzyme can attach and start making DNA.

The result is a huge number of copies of the specific DNA segment produced in a relatively short period of time.

# data[].attributes.attachment_link.title
What is PCR (polymerase chain reaction)?

# data[].attributes.attachment_link.description
PCR is a technique used in the lab to make millions of copies of a particular section of DNA. It was first developed in the 1980s. The polymerase chain reaction (PCR) was originally developed in 1983 by the American biochemist Kary Mullis. He was awarded the Nobel Prize in Chemistry in 1993 for his pioneering work.

# data[].attributes.body
The transplantation of normal genes into cells in place of missing or defective ones in order to correct genetic disorders.

# data[].attributes.body
When organisms with similar characteristics are breed together, often for many generations. Although it keeps the desired traits present, it can cause genetic problems for that organism

# data[].attributes.body
Modern genetic technology can be used to modify the genomes of living organisms. This process is also known as “genetic engineering.” Genes of one species can be modified, or genes can be transplanted from one species to another. Genetic engineering is made possible by recombinant DNA technology. Organisms that have altered genomes are known as transgenic. Most transgenic organisms are generated in the laboratory for research purposes. For example, “knock-out” mice are transgenic mice that have a particular gene of interest disabled. By studying the effects of the missing gene, researchers can better understand the normal function of the gene.

# data[].attributes.body
PCR is a technique used to make many copies of DNA.  The three main steps are Denaturing – when the double-stranded template DNA is heated to separate it into two single strands, Annealing – when the temperature is lowered to enable the DNA primers to attach to the template DNA, and Extending – when the temperature is raised and the new strand of DNA is made by the Taq polymerase enzyme

# data[].attributes.body
cloning is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually.

# data[].attributes.body
During this a cell takes in DNA from outside the cell. The external DNA becomes a component of the cell's DNA.

Transforming bacteria:
DNA joins with a plasmid, which has a genetic marker to make it possible to distinguish bacteria the carry plasmid and bacteria that don't.

# data[].attributes.body
A process also known as "artificial selection" in

# data[].attributes.body
Polymerase chain reaction (

PCR) is a technique used in molecular biology to amplify a single copy or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence.

# data[].attributes.body
It is the breeding of individuals with similar characteristics. It helps to ensure that the characteristics that make each breed unique will be saved.

# data[].attributes.body
Replacing defective or missing genes with genes that are suitable and effective.

# data[].attributes.body
Transplanting genes into the DNA of cells that have defective or missing genes. Used on patients with genetic diseases, to treat or prevent.

# data[].attributes.body
Polymerase chain reaction (PCR) is a technique used in molecular biology to amplify a single copy or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence.

# data[].attributes.body
Polymerase chain reaction (PCR) is a technique used in molecular biology to amplify a single copy or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence.

# data[].attributes.body
Polymerase Chain Reaction- A use of genetic engineering to make millions of copies of DNA with the use of polymers and heat. This tec