Ask a few high school biology questions for the teacher s advice

Analysis: Item a: Mitochondria cannot directly use glucose for respiration;

Item B: The messenger RNA enters the cytoplasmic matrix and is bound to ribosomes for translation;

Item C: DNA polymerase is an intracellular enzyme, which is a protein synthesized from free ribosomes, which needs to be processed by the Golgi apparatus to form a complete spatial structure in order to exert the biological activity of the enzyme.

Your second question involves the following points in the high school knowledge content:

1) The number of layers through the film is considered only for transmembrane transport, and transmembrane transport includes: active transport, free diffusion, and assisted diffusion; Endocytosis and efflux are not transmembrane modes of transport.

2) The nuclear pore is the passage for macromolecular substances (proteins and RNA) to enter and exit the nucleus.

3) Small molecules such as amino acids, water, and inorganic salts are transported across membranes when they enter and leave the nuclear membrane.

Hope it helps you ...

A: Glucose enters the cytoplasm for the first stage of aerobic respiration, oxidizes and decomposes into pyruvate, which then enters the mitochondria, and finally oxidizes and decomposes into CO2 and water.

B: It's not the Golgi apparatus, it's ribosomes.

C: Enzymes translated from ribosomes are to enter the Golgi apparatus and endoplasmic reticulum through the cytoplasmic matrix for further processing.

Macromolecular substances have to pass through the nuclear pores.

Answer: C Analysis: This question mainly examines the process of synthesis and transport of various organic compounds in cells.

Item A absorbs glucose through the cell membrane into the cytoplasmic matrix, where it is broken down into [H] and pyruvate, which then enters the mitochondria and continues to be broken down into carbon dioxide and water. The mRNA formed by transcription in the nucleus of the nucleus comes out through the nuclear pore and binds to the ribosome, ready to begin translation. C DNA polymerase is due to the synthesis of free ribosomes into the nucleus through the nuclear pore to the cytoplasmic matrix.

Positive solution: Elimination method.

A absorbed glucose: C membrane --- cytoplasmic matrix: cannot reach mitochondria.

B Transcribed mRNA: nucleus--- cytoplasmic matrix--- ribosomes.

A does not explain here, because the upstairs has already explained. For B, synaptic vesicles release neurotransmitters after fusing with the presynaptic membrane, according to what you learned, it is generally acetylcholine, then acetylcholine completes the task after contact with the postsynaptic membrane, it generally has two paths: one is inactivated by cholinesterase, and the other is retaken by presynaptic neurons, so how the postsynaptic neurons should be excited and how excited, will not be continuously excited.

Sustained excitation of postsynaptic neurons occurs when acetylcholine cannot be inactivated or retaken by the anterior neurons, resulting in the accumulation of acetylcholine in the synaptic cleft, which continues to interact with the postsynaptic membrane to make the postsynaptic neurons continue to be excited. Increased Ca2+ concentrations do not lead to inactivation of the enzyme and do not affect the reuptake process. Substances like physostigmine can cause the above symptoms, while curare can cause symptoms of item D.

Of course, choose A, the synaptic vesicles are in the synaptosomes, and the fusion with the presynaptic membrane can release neurotransmitters, and the neurotransmitters combine with the postsynaptic membrane to change the potential of the posterior membrane to complete the conduction of impulses.

Calcium ions act as catalysts to promote the fusion of synaptic vesicles with the anterior membrane, which in turn can release neurotransmitters more quickly, thereby speeding up the transmission of nerve impulses. Constant excitation in b is certainly not true, because sustained excitation is not possible without the uninterrupted release of neurotransmitters (only in this case). The c, d options are even more wrong

You first have to understand what sustained excitement is. Neurotransmitters are inactivated when they bind to receptors on the posterior membrane and exert their effects, so sustained excitation does not normally occur.

Pollen is not a somatic cell, it is a germ cell, maize somatic cell 2n = 20, its pollen cell is only 10 (so d is right) there is no allele, so b is wrong, and the separation of alleles will not occur.

Pollen are germ cells that have no homologous chromosomes and no alleles.

Option B, 1 mole of glucose anaerobic respiration produces 2 moles of carbon dioxide, and 1 mole of glucose aerobic respiration produces 6 moles of carbon dioxide, which is three times that of glucose, so it is 3 moles.

In this question D, alcohol is required at a concentration of 50%, 100%, and 95% respectively.

a, count the adjacent sides and their angles.

b, wash off Carnot's solution with alcohol.

c, first wipe off the sodium hydroxide on the surface, and then cut.

All three are wrong.