Biology problems, solutions and explanations!!

Pure yellow gene AA pure black gene AA

aa*aaaa

You can also use the elimination method of option A, the trait has nothing to do with DNA transcription, the offspring are always yellow and black, so it is not a non-allele, and homozygous and homozygous hybrids of different genes cannot appear with the same trait as the parents.

One is AA and the other is AA

After conjugation, it is AA

is option A. It is not possible to transcribe every gene with exclusion method.

B is not good, AA is dominant, and there will be no black.

d No, because this is a relative trait, but not controlled by non-allelic genes.

Seek pinning.

Hello 1b 2a

Because mitochondria and chloroplasts are semi-autonomous organelles, which contain ribosomes, mitochondria, and chloroplasts carry genetic information through ribosome translation and synthesis of proteins to express genetic material, so a pair, mitochondrial chloroplasts are double-layer membrane structures, but the inner mitochondrial membrane is the enzyme required for the third stage of aerobic respiration, that is, ATP synthetase, etc., while chloroplasts carry out photosynthetic light reaction in the thylakoid membrane, and the enzymes contained in the inner membrane of ATP are different from mitochondria... B is wrong, the inner mitochondrial membrane folds inward to form a crest, and the chloroplast thylakoids are stacked to form a matrix, yes, this is the method of expanding the membrane area, C pair, D term cyanobacteria can also carry out photosynthesis without chloroplasts, because they contain enzymes related to photosynthesis, D pair.

According to the function of the cell membrane, option A is right, the reason why the cell is in a relatively stable internal environment is the existence of the cell membrane, most of the intracellular chemical reactions are in the cytoplasmic matrix, B is wrong, C is not the cell membrane, but the organelle membrane divides the cell into many compartments, C is wrong, the "all enzymes" in D are wrong, and some enzymes are in the cytoplasmic matrix. For example, the enzyme that converts glucose into pyruvate, of course, some enzymes act outside the cell, such as: salivary amylase so d wrong.

Hope mine is helpful to you.

The following statements about mitochondria and chloroplasts are incorrect: b

b Mitochondria and chloroplasts are double-membrane structures with (different) types of enzymes in their inner membranes.

A small amount of DNA carried by mitochondria and chloroplasts can be expressed through gene expression.

c The inner mitochondrial membrane folds inward to form a crest, and chloroplast thylakoids stack to form a basal granule, both of which greatly increase the area of the biofilm.

d Cyanobacteria do not have chloroplasts, but they do have chlorophyll and phycocyanin, which can also carry out photosynthesis.

The following statements about biofilm systems are correct: a

A cell membrane separates the cell from the external environment, so that the cell has a relatively stable internal environment.

b Chemical reactions within the cell take place on the surface of the biofilm.

c The cell membrane divides the cells into many compartments.

d The broad membrane area provides a site for the enzyme to attach to.

The answer to the first question is b The enzymes on the inner mitochondrial membrane are enzymes involved in aerobic respiration, and the enzymes on the inner membrane of chloroplast are related to the dark reaction in photosynthesis.

The answer to the second question is a cell membrane separates the cell from the outside world, ensuring that the cell becomes an independent unit and also makes the cell have a relatively stable internal environment; There are many chemical reactions in the answer b, which are done in the cytoplasmic matrix or organelles, not all on the cell membrane; In the answer c, it is the organelle membrane that separates the cell into multiple compartments, such as the endoplasmic reticulum, Golgi apparatus, etc.; The vast majority of enzymes in cells are attached to biological membranes, but not all enzymes.

Mitochondria and chloroplasts both have circular DNA, which is a genetic material independent of the nucleus and can express corresponding proteins And their respective functions are different Enzymes are highly specific to the substrates they act on Therefore, the enzymes in them are not the same b False c Correct Cyanobacteria have no chloroplasts with a photosynthetic sheet for photosynthesis, so the first question is selected b

Question 2 A is correct b Some of the chemical reactions in the cell are carried out on the membrane, and there are many such as protein synthesis DNA, RNA transcription and replication are carried out in the cytoplasm and nucleus c In the cell membrane is the structure that surrounds the cytoplasm and does not divide the cell into compartments d Not all enzymes This comparison is absolutely wrong There are also some enzymes in the cell whose chemical essence is not protein but RNA, and their synthesis has nothing to do with the membrane system Option A

Question 1 B: Mitochondria and chloroplasts are double-membrane structures with different types of enzymes in their inner membranes.

Question 2: A:

b Intracellular chemical reactions take place mainly within the organelles.

c It is mainly the organelle membrane that separates the cell into many compartments.

There is a typo in item d, so it's hard to draw conclusions!

Question 1. b The enzymes in the membrane are definitely different, and if the enzymes are the same, why are the two organelles not the same, and different chemical reactions need to be carried out.

Question 2. c Elimination method, a, the fluid inside and outside the cell makes the cell have a relatively stable internal environment, remember what is in the book. b is all in, there are positive words to pay attention to, and some reactions are carried out in liquid; dAll are not right, and some reactions do not take place on the membrane.

BTW, I'm a freshman this year, and it's a pity that I didn't choose biology, but I still remember that at least I was the first in the class that year. But I've been away from books for a long time, so I'd better look for them again. Come on.

A large number of elements in living organisms include: C, H, O, N, P, S, K, CA, MG, etc., the first half of the C option, "trace elements are very low in the body, but they are indispensable", and the second half of the sentence "such as the composition of chlorophyll is inseparable from the mg element", these two sentences are correct. But to explain the first half of the sentence in the second half of the sentence is wrong.

The chemical compositions of chlorophyll a and b are C55H72O5N4mg and C55H70O6N4mg, respectively

Although the specific mechanism of iron is required for the synthesis of chlorophyll, Fe2+ is required for the active expression of two or three enzymes that catalyze chlorophyll synthesis.

Therefore, fe plays a promoting role in the synthesis of chlorophyll, that is, iron should be involved in the synthesis of chlorophyll. But it is not a component of chlorophyll.

The AB blood group may be born of blood type O, and color blindness is inherited dominantly.

It is a bit of a waste of time to use the direct method for this question, and it is suitable to use the elimination method. First of all, the husband has normal color vision and therefore does not give birth to a daughter with color blindness, so A and C are excluded. Because both are blood type A, they will not give birth to a child with blood type B, so D is wrong. Choose A.

First of all, it is impossible to give birth to blood type B and exclude D because the blood type is bidominant inherited IA

IBI you can find it under the combination, and color blindness is with x recessive, and it is impossible for a girl born to have color blindness, so the answer comes out b

1.From the perspective of color blindness: normal women are XBXB or XBXB, and the second male is XBY, and it is impossible for them to have XBXB among the girls they give birth to, excluding A and C

2.From the perspective of blood type: the female is IAIA or IAI, and the second male is IAIA live IAI, and it is impossible for them to give birth to IBIB or IBI, excluding D

So you can only choose B

The boy's genotype is iixby

mg is not a trace element of the plant body... Plants generally have chloroplasts...

Some amino acids in item B include element S, such as methionine. c, magnesium is not a trace element.