Chapter 15, Problem 12STP

Summary Introduction

To predict:

Two positive and two negative outcomes of using transgenic plants for agricultural purposes

Introduction:

A transgenic organism is one that contains genes from another species. It can be produced by genetic engineering. The process involves cutting or cleaving DNA from one organism into small fragments and then inserting the fragments into a host organism of the same species or different species. Recombinant DNA can also be made by connecting fragments of DNA from different sources. This is inserted into a host organism’s chromosomes. The host organism uses the foreign DNA as if it were its own.

Answer to Problem 12STP

Transgenic plants have the following benefits:

1. Many insect/ viral resistant plants have been developed.
2. Rice plants with increased iron and vitamins were developed.

Negative impacts of transgenic plants:

1. Unknown allergic reactions.
2. Reduced biodiversity

Explanation of Solution

Plants that contain functional recombinant DNA from an organism of different genus are known as transgenic plants. Example: Glowing tobacco plant contains a gene from a firefly.

Positive outcomes- There are many benefits of growing transgenic plants.

1. Many species of plants have been genetically engineered to be more resistant to insects and viruses. Transgenic crops resistant to herbicide and insecticide such as soya beans, corn, cotton and canola are grown in many countries.
2. Some commercially grown crops like rice are genetically engineered to have more iron and vitamins so that they are healthier. These plants can reduce malnutrition in Asian countries.

Negative outcomes- Despite many positive impacts of transgenic plants on environment and health there are few negative impacts also.

1. Transgenic crops are not considered to be absolutely safe. Many produce unknown allergic reactions on their consumption. Hence they are considered unsafe for long term use.
2. The unwanted spread of transgenic plants has reduced the biodiversity. Many wild varieties are becoming extinct because they are not favored.