Key points of knowledge about biological plant tissue culture in senior high school 1. Is plant tissue culture asexual?
Answer: Although in the process of plant tissue culture, the cultured cells only undergo mitosis and not meiosis, the propagation type of plant tissue culture should depend on the culture materials used. If the culture materials used are somatic cells, such as root tips and stem tips, it belongs to asexual reproduction. Anthers cultured in vitro should belong to sexual reproduction.
2. Why should virus-free plants be cultivated with shoot tips?
A: Because the virus is transported slowly, and there are no vascular bundles in the meristem of the stem tip, the virus can only be transmitted through plasmodesmata, which can't keep up with the speed of cell division and growth, so the number of viruses at the growing point is very small and almost undetectable.
3. Is anther culture in vitro the same as pollen culture in vitro?
Answer: Anther culture in vitro is to inoculate the anthers that have developed to a certain stage into the culture medium, change the development procedure of pollen grains in the anthers, make them split into cell clusters, then differentiate into embryoids, form callus, and then differentiate from callus into plants. Pollen culture in vitro refers to the technology of separating pollen from anther and culturing it in vitro with a single pollen grain as explant. Because pollen is haploid, plants induced by callus or embryoid development are haploid, and are not interfered by anther anther connective, anther wall, filament and other somatic cells. It can be seen that anther culture in vitro is different from pollen culture in vitro. Anther culture in vitro belongs to organ culture, and pollen culture in vitro belongs to cell culture. But the purpose of culture is the same, and it is necessary to induce pollen cells to develop into haploid cells and eventually develop into haploid plants.
The exercise questions and answers of biological plant tissue culture in senior high school 1, the basic principle of plant tissue culture, the sequence of culture process and the induced phytohormones are () respectively.
① Totipotency of cells ② Isolated plant organs, tissues or cells ③ Roots and buds.
④ Auxin and cytokinin ⑤ Auxin and ethylene ⑤ Callus.
⑦ Redifferentiate ⑧ Dedifferentiate ⑨ Plant.
A. ① ② ⑧ ③ ⑨ and 4B. ① ② ⑧ ③ ⑨ and ⑤.
C. 1⑤ 2⑨ 3⑧ and ⑧ D.12 ⑨ 319; 3 19; ④
2. When carrot phloem cells are cultured into seedlings, what is not needed in the following conditions is ().
A. Cells with intact nuclei B. Some nutrients and plant hormones
C. in vitro state D. introduction of the specified gene.
3, in the process of dedifferentiation of plant organs, tissues or cells in vitro to form callus, which of the following conditions is not necessary ()
A. Adequate lighting B. Appropriate temperature
C. Disinfection and sterilization D. Appropriate nutrition and hormones
4. Sweet potato is easy to accumulate virus after many years of planting, leading to variety degradation. At present, virus-free seedlings are rapidly propagated by shoot apex meristem culture in vitro to ensure the quality and yield level of this variety. This process of obtaining seedlings by meristem culture in vitro does not involve cells ().
A. totipotency of mitotic differentiation and meiosis
5, with highly differentiated plant cells, tissues and organs for tissue culture can form callus, the following statement is wrong ()
A. Callus is formed by dedifferentiation and division of cells.
B. the cells of callus are not totipotent.
C. Callus is composed of loosely arranged parenchyma cells.
D. Callus can form embryoid structure with rooting and germination ability.
1、A
Analysis: The theoretical basis of plant tissue culture is the totipotency of cells, which first dedifferentiates and then redifferentiates. Auxin and cytokinin can promote cell division and differentiation, and the ratio of auxin and cytokinin will be different in different periods of culture, so they are indispensable special additives.
2、D
Analysis: Plant cells are totipotent, that is, each cell contains a whole set of genetic material of somatic cells of this species. In tissue culture, tissues or cells that need to be separated (with intact nuclei) need certain nutrients and plant hormones, and no specified genes are introduced.
3. A.
Analysis: No light is needed for dedifferentiation, because the cells cultured at this stage have not yet formed chloroplasts and cannot carry out photosynthesis.
4、C
Analysis: The meristem of shoot tip is used for in vitro culture, and the cultured cells undergo mitosis, which belongs to asexual reproduction and does not involve meiosis.
5、B