What is the principle of the gene transplantation of Bacillus thuringiensis into cotton and the cult

Broadly speaking, it is genetic engineering or genetic engineering. First, the insecticidal gene of BT needs to be modified to be expressed in cotton, and then it is transferred into cotton cells through pollen tube channel transformation technology or Agrobacterium-mediated binding transfer technology, so that it can be randomly or specifically integrated into cotton chromosomes, and cotton plants can be selected, cultivated and regenerated through resistance.

Principle of genetic identity (genes with different DNA sequences but encoding the same protein, have the same function.) ), the principle of genetic recombination, the principle of genetic transformation, the principle of plant cell totipotency, etc.

Gene synthesis: Through artificial synthesis technology, the gene sequence of bacterial BT is modified into the "cotton gene" sequence of cotton preference.

DNA recombination principle: through genetic recombination, the above-mentioned modified BT gene and the promoter and terminator required for expression in cotton are spliced into a complete "cotton gene" that can be efficiently expressed in cotton. At the same time, genetic marker genes that facilitate future screening, such as herbicide resistance genes, are added.

Genetic transformation: The above genes are transferred into cotton cells through pollen duct channels or gene guns or Agrobacterium-mediated binding transfer, and are inserted into cotton chromosomes through genetic recombination.

Tissue culture: Using the principle of plant cell totipotency, the above-mentioned transformed cells are cultured into transgenic plants through tissue culture and screening.

Cotton transgenic with Bacillus thuringiensis contains Bt toxic protein, and pests will die if they eat cotton containing Bt toxic protein.

Genetic engineering **Genetic technology) and plant tissue culture technology.

Answer B: This question is easy to choose C, genetic engineering is a technical means, not a biological principle. The cultivation and utilization of insect-resistant cotton is a technical means of genetic engineering to recombine the gene auspicious brigade, and the principle of gene expression is used in the early preparation of DNA double bonds.

C test question analysis: transgenic technology refers to the use of scientific means to extract the required genes from a certain organism, transfer them into another organism, and recombine the genes with another organism, so as to cultivate genetically modified organisms, so the technology of producing penicillin with Escherichia coli belongs to transgenic technology, scientists transfer the Bacillus thuringiensis insect resistance gene into cotton plants, and cultivate transgenic insect-resistant cotton with cotton bollworm resistance, which shows that it is genes that control biological traits, so genes control biological traits, Because the genetic material has changed, the insect-resistant characteristics of insect-resistant cotton can be inherited, and the insect-resistant traits can help to improve the yield of cotton, but not all cotton field pests have insect-resistant effects, so C.

Genetically modified insect-resistant cotton refers to cotton varieties with exogenous insect resistance genes integrated on the chromosomes of cotton cells. The insect resistance gene is usually the BT gene of Bacillus thuringiensis. Therefore, genetically modified insect-resistant cotton is also known as transgenic BT insect-resistant cotton.

It is the introduction of the BT gene of Bacillus thuringiensis into the mesophyll cells of the recipient cell ** gene insect-resistant cotton). Bacillus thuringiensis can produce a BT insecticidal protein during the metabolism process, which has a toxic effect on a variety of pests, and is widely used as a biological pesticide in vegetables, melons and fruits and other crops. After the BT gene was transferred into the cells of cotton plants by Agrobacterium tumefaciens mediation, the BT insecticidal protein could also be synthesized in cotton plants.

So the insect resistance gene product here is this bt protein!

Answer D: This question tests the knowledge related to the detection and expression of the target gene. To detect whether the gene of interest is expressed, usually the detection product of the antigen scattering-antibody reaction is used on the molecular water and slag digging to see if it has the corresponding traits, so option d is correct. Quietly.

The recombinant DNA molecule adds a base pair, which does not necessarily lead to the loss of toxicity of the toxic protein, and the insect resistance gene of insect-resistant cotton can be transmitted to the adjacent crops through pollen, thus causing genetic contamination.

Answer] C Answer Analysis] Test Analysis: Genetically modified technology refers to the use of scientific means to extract the required genes from a certain organism, transfer them into another organism, and recombine them with the genes of another organism, so as to breed genetically modified organisms, so the technology of producing penicillin with Escherichia coli belongs to transgenic technology, and scientists transferred the Bacillus thuringiensis insect resistance gene into the trembling state of cotton plants, and cultivated into genetically modified insect-resistant cotton resistant cotton resistant to cotton bollworm, indicating that it is genes that control biological traits from the source of eggplant. Therefore, genes control the traits of organisms, because the genetic material has changed, so the insect-resistant characteristics of insect-resistant cotton can be inherited, and the insect-resistant traits can be conducive to improving the yield of cotton, but not all cotton field pests have insect-resistant effects, so choose C.

Test Center: This question examines the application of genetically modified technology.

Huai Yu Answer] d

Answer analysis] test question analysis: whether the experiment is successful depends on whether the cotton plant has insect resistance traits, so the most convenient way is to detect whether the cotton plant has the corresponding insect resistance traits, so d is correct. Insect resistance gene detection uses DNA hybridization technology, and it may not be successfully expressed, so A is wrong.

The detection of anti-insect gene products requires antigen-antibody hybridization, which is inconvenient, so B is wrong. Genetic engineering technology does not change the structure of the nucleus and does not generate new nuclei, so C is wrong.

(1) Obtaining the target gene from donor cells requires the use of restriction enzymes Restriction enzymes are mainly isolated and purified from prokaryotes, which can recognize a specific nucleotide sequence of double-stranded DNA molecules, and break the phosphodiester bond between two nucleotides at a specific site in each strand to form a sticky end or blunt end

2) The four steps to carry out genetic engineering operations are: acquisition of the target gene; Construction of gene expression vectors (or binding of the target gene to the carrier); Introduce the gene of interest into the recipient cell; Detection and identification of target genes

So the answer is: 1) Restriction enzyme phosphodiester bond microorganisms.

A restriction enzyme can only recognize a specific nucleotide sequence and cleave at a specific cut-off point (2) Acquisition of the gene of interest Construction of gene expression vector (or binding of the gene of interest to the carrier Gene of interest) Import of the gene of interest into the recipient cell Detection and identification of the gene of interest.