High School Biology Questions! Urgent! High School Biology Problems

Insect resistance genes don't necessarily have antibiotic resistance, right? Moreover, the marker gene is not necessarily introduced into cotton cells along with the insect resistance gene. Here, the antibiotic gene, the insect resistance gene, and the marker gene are three different genes and cannot be confused.

The corresponding shape is produced, indicating that the gene has been transferred to the cells of cotton and has been expressed, which is also the most common method used in scientific research. The isolation of the target gene can only indicate that the gene has been transferred into the cell, but it is still unknown whether it is expressed, because the gene expression is regulated, and it may not be able to be expressed with this gene, and the differentiation of cells can be referenced.

Gene expression refers to the transcription and translation of the gene of interest into a protein that exhibits the corresponding trait. The key to detecting whether the protein is expressed or whether it shows the corresponding traits.

Resistance to the antibiotic in a can only indicate the introduction of the gene of interest.

The marker gene can be detected in b, and it is not even certain whether the target gene is introduced into the recipient cell, let alone expressed.

The c trait is embodied by the protein and ultimately by the gene, and the detection of the trait can certainly indicate the expression of the gene.

The isolation of the target gene only indicates that the target gene has been introduced, but it does not mean that it is expressed.

Because the target gene is expressed, if the gene is expressed, the shape of the species will also change accordingly. For A: The introduction of insect resistance genes does not produce antibiotics.

B: Marker gene detected, indicating successful introduction, but not necessarily successful gene expression. It's not easy to code words on mobile phones. Thank you.

A is wrong because antibiotics and insect resistance (sex) are two different concepts.

B is wrong because the expression of the marker gene is approximately equal to the expression of the target gene (insect resistance gene), and it is possible that the marker gene is expressed but the target gene is not expressed.

Higher animal egg cells minus 2 metaphase have no homologs.

The answer is: a.

The chemical essence of DNA polymerase is protein, which is synthesized on ribosomes, ribosomes have a membrane-free structure, and the synthesized DNA polymerase works in the cell, does not need to be secreted outside the cell, and does not use the Golgi apparatus and does not form vesicles.

While the other three substances require the Golgi apparatus to form vesicles and secrete them outside the cell.

The answer is c! Reason: At point A, the concentration of CO2 has reached its maximum and begins to decline, that is, at this point, the CO2 consumed by photosynthesis is equal to the CO2 released by respiration, so before point A, chloroplasts begin to absorb CO2;

At point B, the CO2 concentration has continued to drop to the initial concentration, and it is clear that the photosynthetic intensity is greater than the respiration intensity;

At point C, only the CO2 released by the respiration intensity is equal to the CO2 absorbed by photosynthesis, so the photosynthesis intensity at this time is greater than zero, therefore, C is correct;

All things considered, the CO2 concentration decreased in 24 hours, indicating that the organic matter accumulation of the plant was greater than zero.

The slope of CA A is 0, and the respiration and photosynthetic rate are equal, so CO2 must be absorbed (otherwise there is no photosynthesis).

b At time b, the slope is the largest, and the photosynthetic rate is the largest, and the photosynthetic rate is greater than the respiration rate.

c As with point a, the respiratory photosynthesis is not 0

d Looking at the figure, the CO2 concentration at the end of the line is significantly smaller than at the beginning, which indicates that the CO2 has been used, that is, there is a net accumulation.

The answer to C is analyzed as follows:

At the two inflection points A and C, photosynthesis intensity = respiration intensity, excluding b; At the same time, because the intensity of synthesis = the intensity of respiration at point A, at point A, the chloroplast does not absorb carbon dioxide from the outside world, excluding option A; At point C, the synthetic rate is equal to the respiration rate and is greater than zero, so C is chosen; Since the total amount of carbon dioxide decreases after one day, organic matter accumulates and eliminates d

The experience of people who have come before you tells you that you can't answer like that.

The first empty: expression is said to be the gene, and here is the trait. And if the first blank cannot be expressed, the reduction in salt resistance is due to the expression of the salt resistance gene, not the inexpressibility.

The second emptiness: mutation and transformation are two different concepts. Genetic mutations refer to sudden, heritable mutations in genomic DNA molecules.

The process of causing cell-specific changes and taking advantage of the totipotency of plants to regenerate complete transgenic plants from a transformed cell through cell or tissue culture is called plant gene transformation.

Reduced and mutant belong to the category of biological terms, which are very common in ordinary questions, do more biological problems, accumulate and accumulate.

I haven't heard of this stuff.

It seems that I only know 17 questions and choose D ......The task is so difficult.

It is pyruvate and not glucose that can enter the mitochondria, so C is wrong.

Question 23 C is false, deoxyribose does not have phosphorus and is a monosaccharide, C5H10O4

32 questions choose C