Problem 12 - Biology Today and Tomorrow Without Physiology

Question

Match the terms with the best description. _______ DNA fingerprint _______ Ti plasmid _______ nucleic acid _______ hybridization eugenics _______ restriction enzyme _______ transgenic _______ GMO a. having a foreign gene b. cuts DNA at a specific sequence c. a person's unique collection of short tandem repeats d. base pairing of DNA or DNA and RNA from different sources e. selecting "desirable" traits f. genetically modified g. used in some gene transfers

Step-by-Step Solution

Answer

DNA fingerprint - c, Ti plasmid - g, nucleic acid hybridization - d, eugenics - e, restriction enzyme - b, transgenic - a, GMO - f.

Step 1: Match DNA fingerprint

The hint indicates a person's unique collection of short tandem repeats. This definition matches option **c**.

Step 2: Match Ti plasmid

The Ti plasmid is commonly used for gene transfer. This aligns with option **g**.

Step 3: Match Nucleic Acid Hybridization

Hybridization in molecular biology refers to the base pairing of DNA or DNA and RNA from different sources, which corresponds to option **d**.

Step 4: Match Eugenics

Eugenics involves selecting 'desirable' traits, which matches option **e**.

Step 5: Match Restriction Enzyme

A restriction enzyme cuts DNA at specific sequences, closely fitting the description in option **b**.

Step 6: Match Transgenic

Transgenic organisms have had foreign genes inserted into their genome, as described in option **a**.

Step 7: Match GMO

A genetically modified organism (GMO) aligns with having been genetically modified, option **f**.

Key Concepts

DNA fingerprint

DNA fingerprints are unique to each individual, much like actual fingerprints. They consist of a specific combination of short sequences found in a person's DNA known as short tandem repeats (STRs). These STRs are repeated sequences of DNA that vary greatly between individuals.

• The technique to create a DNA fingerprint involves extracting DNA from cells and using techniques like PCR to amplify the regions of interest.
• By comparing the STR patterns of different individuals, forensic scientists can determine relationships or identify individuals in criminal investigations.

The uniqueness of STR patterns means that DNA fingerprints can differentiate individuals—even siblings have different DNA fingerprints. This makes DNA fingerprinting a powerful tool for identity verification and forensic science.

Ti plasmid

The Ti plasmid, short for Tumor-inducing plasmid, is a naturally occurring plasmid found in the bacterium Agrobacterium tumefaciens. This plasmid plays a key role in genetic engineering, especially in plants.

• It facilitates the transfer of genes to plant cells, essentially serving as a vehicle for introducing new genes.
• The Ti plasmid transfers part of its DNA, called the T-DNA, into the plant genome, causing "crown gall disease," a plant tumor in nature.

In genetic engineering, scientists harness this process to introduce beneficial genes into plants without causing disease. By replacing the tumor-inducing genes with desired genes, researchers can create genetically modified plants that exhibit new traits, such as resistance to pests or improved nutrition.

restriction enzyme

Restriction enzymes, also known as restriction endonucleases, are proteins that cut DNA at specific sequences, known as restriction sites. These sites are typically palindromic and are 4 to 8 base pairs in length.

• Discovered in bacteria, these enzymes serve as a defense mechanism against viruses by chopping up foreign DNA.
• Scientists use restriction enzymes in laboratories to cut DNA into fragments at desired locations, facilitating DNA manipulation for cloning and analysis.

There are numerous types of restriction enzymes, each with its own specific recognition sequence. The ability to cut precisely makes them essential tools in molecular biology, allowing researchers to "cut and paste" DNA sequences, which is crucial in genetic engineering and recombinant DNA technology.

transgenic organisms

Transgenic organisms have been altered using genetic engineering techniques to carry foreign genes—that is, genes from another species.

• This process involves the insertion of genes using vectors, such as plasmids or viruses, to integrate the new DNA into the organism's genome.
• Transgenic plants, for example, might possess resistance to herbicides, while transgenic animals could produce pharmaceuticals.

Creating a transgenic organism involves several steps, including identifying the gene of interest, selecting the appropriate vector, and ensuring the organism expresses the desired traits. These steps rely on accurate gene transfer and effective expression of the inserted gene, which can lead to enhanced or novel traits beneficial for agriculture, medicine, and industry.

GMO

Genetically Modified Organisms (GMOs) are organisms—be they plants, animals, bacteria, or other organisms—whose genetic material has been altered through genetic engineering techniques.

• GMOs are created to enhance desirable traits such as increased resistance to pests, improved nutritional content, or faster growth rates.
• These modifications are achieved by transferring specific genes from one organism to another or altering an organism’s existing DNA.

GMOs have sparked discussion and debate globally around food safety, environmental protection, and ethical considerations. However, they also offer significant advantages, like the potential to address food shortages and improve the nutritional content of food. Understanding GMOs and their impact is crucial as they become increasingly prevalent in agriculture and biotechnology.