The structure of a single protein is determined by a group of genes. Levels of structural organization of proteins. Spatial organization of protein molecules
1) a group of genes 2) one genome
3) one DNA molecule 4) a set of genes of an organism
2. One triplet of DNA carries information about:
1) sequence of amino acids in a protein molecule
2) a characteristic of the organism 3) an amino acid in the molecule of the synthesized protein
4) the composition of the RNA molecule
3. The theory of matrix synthesis was proposed by:
1) J. Watson 3) G. De Vries 2) N. Koltsov 4) T. Morgan
4. The gene encodes information about the sequence of monomers in the molecule:
1) tRNA 3) protein 2) glycogen 4) DNA
5. Which of the processes occurs in cells of any structure and function:
1) protein synthesis 3) metabolism 2) mitosis 4) meiosis
6. Triplets are called anticodons:
1) DNA 3) t-RNA 2) i-RNA 4) r-RNA
7. The concept of “transcription” refers to the process:
1) DNA duplication 2) mRNA synthesis on DNA
3) transfer of mRNA to ribosomes 4) creation of protein molecules on the polysome
8. Plastic exchange consists mainly of reactions:
1) decomposition of organic substances 2) decomposition of inorganic substances
3) synthesis of organic substances 4) synthesis of inorganic substances
9. A section of a DNA molecule that carries information about one protein molecule is: 1) gene 2) phenotype 3) genome 4) genotype
10. Protein synthesis in a prokaryotic cell occurs:
1) on ribosomes in the nucleus 2) on ribosomes in the cytoplasm 3) in the cell wall
4) on the outer surface of the cytoplasmic membrane
11. Transcription in eukaryotes occurs in:
1) cytoplasm 2) endoplasmic reticulum 3) lysosomes 4) nucleus
12. Protein synthesis occurs in:
1) granular endoplasmic reticulum
2) smooth endoplasmic reticulum 3) nucleus 4) lysosomes
13. The broadcast process does not occur:
1) in the cytoplasm 2) in the nucleus 3) in mitochondria
4) on the membranes of the rough endoplasmic reticulum
14. One amino acid is encoded:
1) four nucleotides 2) two nucleotides
3) one nucleotide 4) three nucleotides
15. A triplet of ATC nucleotides in a DNA molecule will correspond to a codon of an mRNA molecule:
1) TAG 2) UAG 3) UTC 4) TsAU
16. On the membranes of the granular endoplasmic reticulum, synthesis occurs: 1) ATP; 2) carbohydrates; 3) lipids; 4) proteins.
17. Of the total RNA content of a cell, the share of i-RNA is approximately: 1) 0.5-1%; 2) 10%; 3) 50%; 4) 90%.
18. Among the RNA molecules, the most numerous are:
1) t-RNA; 3) r-RNA; 2) mRNA; 4) all types of RNA are approximately equal.
Q 1. Select the characteristics that correspond to the characteristics of protein metabolism in the human body.
A) The breakdown of protein molecules into amino acids occurs in cells
B) The breakdown of protein molecules into amino acids occurs in the digestive tract
B) The end products of decomposition are carbon dioxide, water, urea and other substances
D) The end products of breakdown are glucose, fatty acids
D) The daily requirement is 100-150 g
E) Daily protein requirement - 400-600 g
B 2. Determine the sequence of reactions of matrix protein synthesis
A) Combination of mRNA with a ribosome
B) Enzymatic cleavage of hydrogen bonds of the DNA molecule
B) Synthesis of mRNA on a section of one of the DNA chains
D) Combination of t-RNA with the ribosome and recognition of its codes
E) Attaching an amino acid to tRNA
E) Separation of the protein chain from tRNA
B 3. Correlate the features of the processes of protein biosynthesis and photosynthesis
Process Features
1) Ends with the formation of carbohydrates
2) Starting substances - amino acids
3) It is based on matrix synthesis reactions
4) Starting substances - carbon dioxide and water
5) ATP is synthesized during the process
6) ATP is used to carry out the process
Processes
A) Protein biosynthesis
B) Photosynthesis
Q 4. Establish a correspondence between a biological process and its properties:
PROPERTIES 4. Establish a correspondence between the biological process and its properties:
PROPERTY
A) is the synthesis of RNA on a DNA template
B) occurs in the cytoplasm
B) doubling of the DNA molecule
D) occurs on ribosomes
D) represents protein synthesis
BIOLOGICAL PROCESS
1) transcription
2) broadcast
3) replication
Q 5. Indicate the sequence of phenomena and processes that occur during protein synthesis:
A) entry of an mRNA molecule from the nucleus into the cytoplasm
B) interaction of a tRNA molecule carrying the first amino acid of a given protein with a ribosome in complex with mRNA
B) formation of a peptide bond
D) synthesis of an mRNA molecule on a DNA template
D) translation termination
E) binding of an mRNA molecule to a ribosome
Q 6. Construct a sequence of translation reactions by writing out the numbers in the required order.
A) Addition of an amino acid to tRNA
B) The beginning of the synthesis of the polypeptide chain on the ribosome
B) Attachment of mRNA to the ribosome
D) End of protein synthesis
E) Elongation of the polypeptide chain
E) Connection of a codon with an anticodon
Q 7. Establish the sequence of stages of protein synthesis:
A) Entry of an mRNA fragment into the acceptor site of the functional center of the ribosome (FCR);
B) Attachment of t-RNA with an amino acid to the corresponding codon of i-RNA in the acceptor site of the FCR;
B) Movement of t-RNA with growing protein to the donor site of the FCR;
D) Transcription;
E) Elongation of the polypeptide chain by one amino acid;
E) Attachment of amino acids to the corresponding tRNAs.
One of the features of proteins is their complex structural organization. All proteins have a primary, secondary and tertiary structure, and those that have two or more PCPs also have a quaternary structure (QS).
Protein primary structure (PSB) – this is the order of alternation (sequence) of amino acid residues in the PPC.
Even proteins that are identical in length and amino acid composition can be different substances. For example, from two amino acids you can make 2 different dipeptides:
With the number of amino acids equal to 20, the number of possible combinations is 210 18. And if we consider that in the PPC each amino acid can occur more than once, then the number of possible options is difficult to count.
Determination of the primary protein structure (PSB).
The PBP of proteins can be determined using phenylthiohydantoin
method
. This method is based on the interaction reaction phenylisothiocyanate
(FITC) with α-AA. As a result, a complex of these two compounds is formed - FITZ-AK
.
For example, consider the peptide 
in order to determine its PBP, that is, the sequence of amino acid residues.
FITC interacts with the terminal amino acid (a). A complex is formed FTG-a, it is separated from the mixture and the identity of the amino acid is determined A. For example, this - asn
etc. All other amino acids are sequentially separated and identified. This is a labor-intensive process. Determining the PBP of a medium-sized protein takes several months.
Priority in decoding the PSB belongs to Sengeru(1953), who discovered insulin PSB (Nobel Prize winner). The insulin molecule consists of 2 PPCs - A and B.
The A chain consists of 21 amino acids, the B chain of 30. The PPCs are connected to each other by disulfide bridges. The number of proteins whose PBP has been determined currently reaches 1500. Even small changes in the primary structure can significantly change the properties of a protein. The erythrocytes of healthy people contain HbA - when replaced in the chain of HbA, in the 6th position glu on shaft a serious illness occurs sickle cell anemia, in which children born with this anomaly die at an early age. On the other hand, there are possible options for changing PSB, which do not affect its physicochemical and biological properties. For example, HbC contains a b-chain in the 6th position instead of glu-lys, HbC is almost no different in its properties from HbA, and people who have such Hb in their erythrocytes are practically healthy.
PSB stability is provided mainly by strong covalent peptide bonds and, secondarily, by disulfide bonds.
Protein secondary structure (PSS).
The PPCs of proteins are highly flexible and acquire a specific spatial structure or conformation. There are 2 levels of such conformation in proteins - this is the VSB and the tertiary structure (TSB).
VSB – this is the configuration of the PPC, that is, the way it is laid or twisted into some conformation, in accordance with the program embedded in the P SB.
Three main types of VSB are known:
1) -spiral;
2) b-structure(folded layer or folded leaf);
3) a messy tangle.
-spiral .
Its model was proposed by W. Pauling. It is most likely for globular proteins. For any system, the most stable state is the one corresponding to the minimum free energy. For peptides, this state occurs when the CO– and NH– groups are connected to each other by a weak hydrogen bond. IN a -spirals The NH– group of the 1st amino acid residue interacts with the CO– group of the 4th amino acid. As a result, the peptide backbone forms a helix, each turn of which contains 3.6 AA residues.
1 spiral pitch (1 turn) = 3.6 AA = 0.54 nm, elevation angle – 26°
The twisting of the PPC occurs clockwise, that is, the spiral has a right motion. Every 5 turns (18 AC; 2.7 nm) the PPC configuration is repeated.
Stabilizing VSB primarily by hydrogen bonds, and secondly by peptide and disulfide bonds. Hydrogen bonds are 10-100 times weaker than ordinary chemical bonds; however, due to their large number, they provide a certain rigidity and compactness of the VSB. The side R-chains of the a-helix face outward and are located on opposite sides of its axis.
b -structure .
These are folded sections of the PPC, shaped like a leaf folded into an accordion. PPC layers can be parallel if both chains start from the N- or C-terminus.
If adjacent chains in a layer are oriented with opposite ends N–C and C–N, then they are called antiparallel.
parallel
antiparallel
The formation of hydrogen bonds occurs, as in the a-helix, between the CO– and NH– groups.
Protein biosynthesis.
1. The structure of one protein is determined:
1) a group of genes 2) one gene
3) one DNA molecule 4) the totality of genes of an organism
2. The gene encodes information about the sequence of monomers in the molecule:
1) tRNA 2) AA 3) glycogen 4) DNA
3. Triplets are called anticodons:
1) DNA 2) t-RNA 3) i-RNA 4) r-RNA
4. Plastic exchange consists mainly of reactions:
1) decomposition of organic substances 2) decomposition of inorganic substances
3) synthesis of organic substances 4) synthesis of inorganic substances
5. Protein synthesis in a prokaryotic cell occurs:
1) on ribosomes in the nucleus 2) on ribosomes in the cytoplasm 3) in the cell wall
4) on the outer surface of the cytoplasmic membrane
6. The broadcast process occurs:
1) in the cytoplasm 2) in the nucleus 3) in mitochondria
4) on the membranes of the rough endoplasmic reticulum
7. Synthesis occurs on the membranes of the granular endoplasmic reticulum:
1)ATP; 2) carbohydrates; 3) lipids; 4) proteins.
8. One triplet encodes:
1. one AK 2 one sign of an organism 3. several AKs
9. Protein synthesis is completed at the moment
1. recognition of a codon by an anticodon 2. appearance of a “punctuation mark” on the ribosome
3. entry of mRNA into the ribosome
10. The process that results in reading information from a DNA molecule.
1.translation 2.transcription 3.transformation
11. The properties of proteins are determined...
1. secondary structure of the protein 2. primary structure of the protein
3.tertiary protein structure
12. The process by which an anticodon recognizes a codon on mRNA
13. Stages of protein biosynthesis.
1.transcription, translation 2.transformation, translation
3.transorganization, transcription
14. The anticodon of tRNA consists of UCG nucleotides. Which DNA triplet is complementary to it?
1.UUG 2. TTC 3. TCG
15. The number of tRNAs involved in translation is equal to the number:
1. mRNA codons that encode amino acids 2. mRNA molecules
3 Genes included in the DNA molecule 4. Proteins synthesized on ribosomes
16. Establish the sequence of arrangement of i-RNA nucleotides during transcription from one of the DNA strands: A-G-T-C-G
1) U 2) G 3) C 4) A 5) C
17. When a DNA molecule replicates, it produces:
1) a thread that has broken up into separate fragments of daughter molecules
2) a molecule consisting of two new DNA strands
3) a molecule, half of which consists of an mRNA strand
4) a daughter molecule consisting of one old and one new DNA strand
18. The template for the synthesis of an mRNA molecule during transcription is:
1) the entire DNA molecule 2) completely one of the chains of the DNA molecule
3) a section of one of the DNA chains
4) in some cases one of the chains of the DNA molecule, in others – the entire DNA molecule.
19. The process of self-duplication of a DNA molecule.
1.replication 2.reparation
3. reincarnation
20. During protein biosynthesis in a cell, the energy of ATP is:
1) consumed 2) stored
3) is not consumed or allocated
21. In the somatic cells of a multicellular organism:
1) different set of genes and proteins 2) same set of genes and proteins
3) the same set of genes, but a different set of proteins
4) the same set of proteins, but a different set of genes
22.. One triplet of DNA carries information about:
1) sequence of amino acids in a protein molecule
2) characteristic of the organism 3) amino acid in the molecule of the synthesized protein
4) the composition of the RNA molecule
23. Which of the processes does not occur in cells of any structure and function:
1) protein synthesis 2) metabolism 3) mitosis 4) meiosis
24. The concept of “transcription” refers to the process:
1) DNA duplication 2) mRNA synthesis on DNA
3) transfer of mRNA to ribosomes 4) creation of protein molecules on the polysome
25. A section of a DNA molecule that carries information about one protein molecule is:
1)gene 2)phenotype 3)genome 4)genotype
26. Transcription in eukaryotes occurs in:
1) cytoplasm 2) endoplasmic membrane 3) lysosomes 4) nucleus
27. Protein synthesis occurs in:
1) granular endoplasmic reticulum
2) smooth endoplasmic reticulum 3) nucleus 4) lysosomes
28. One amino acid is encoded:
1) four nucleotides 2) two nucleotides
3) one nucleotide 4) three nucleotides
29. A triplet of ATC nucleotides in a DNA molecule will correspond to a codon of an mRNA molecule:
1) TAG 2) UAG 3) UTC 4) TsAU
30. Punctuation marksgenetic code:
1. encode certain proteins 2. trigger protein synthesis
3. stop protein synthesis
31. The process of self-duplication of a DNA molecule.
1. replication 2. reparation 3. reincarnation
32. Function of mRNA in the process of biosynthesis.
1.storage of hereditary information 2.transport of AK to ribosomes
3.supplying information to ribosomes
33. The process when tRNAs bring amino acids to ribosomes.
1.transcription 2.translation 3.transformation
34. Ribosomes that synthesize the same protein molecule.
1.chromosome 2.polysome 3.megachromosome
35. The process by which amino acids form a protein molecule.
1.transcription 2.translation 3.transformation
36. Matrix synthesis reactions include...
1.DNA replication 2.transcription, translation 3.both answers are correct
37. One triplet of DNA carries information about:
1.Sequences of amino acids in a protein molecule
2.Location of a specific AK in the protein chain
3. Characteristics of a specific organism
4. Amino acid included in the protein chain
38. The gene encodes information about:
1) the structure of proteins, fats and carbohydrates 2) the primary structure of protein
3) nucleotide sequences in DNA
4) amino acid sequences in 2 or more protein molecules
39. mRNA synthesis begins with:
1) separation of DNA into two strands 2) interaction of the RNA polymerase enzyme and gene
3) gene duplication 4) gene decay into nucleotides
40. Transcription occurs:
1) in the nucleus 2) on ribosomes 3) in the cytoplasm 4) on the channels of the smooth ER
41. Protein synthesis does not occur on ribosomes in:
1) tuberculosis pathogen 2) bees 3) fly agaric 4) bacteriophage
42. During translation, the matrix for assembling the polypeptide chain of a protein is:
1) both strands of DNA 2) one of the strands of the DNA molecule
3) an mRNA molecule 4) in some cases one of the DNA chains, in others – an mRNA molecule
Protein biosynthesis.1. The structure of one protein is determined:
1) a group of genes 2) one gene
3) one DNA molecule 4) the totality of genes of an organism
2. The gene encodes information about the sequence of monomers in the molecule:
1) tRNA 2) AA 3) glycogen 4) DNA
3. Triplets are called anticodons:
1) DNA 2) t-RNA 3) i-RNA 4) r-RNA
4. Plastic exchange consists mainly of reactions:
1) decomposition of organic substances 2) decomposition of inorganic substances
3) synthesis of organic substances 4) synthesis of inorganic substances
5. Protein synthesis in a prokaryotic cell occurs:
1) on ribosomes in the nucleus 2) on ribosomes in the cytoplasm 3) in the cell wall
6. The broadcast process occurs:
1) in the cytoplasm 2) in the nucleus 3) in mitochondria
4) on the membranes of the rough endoplasmic reticulum
7. Synthesis occurs on the membranes of the granular endoplasmic reticulum:
1)ATP; 2) carbohydrates; 3) lipids; 4) proteins.
8. One triplet encodes:
1. one AK 2 one sign of an organism 3. several AKs
13. Stages of protein biosynthesis.
1.transcription, translation 2.transformation, translation
3.transorganization, transcription
14. The anticodon of tRNA consists of UCG nucleotides. Which DNA triplet is complementary to it?
1.UUG 2. TTC 3. TCG
2) a molecule consisting of two new DNA strands
4) a daughter molecule consisting of one old and one new DNA strand
18. The template for the synthesis of an mRNA molecule during transcription is:
1) the entire DNA molecule 2) completely one of the chains of the DNA molecule
4) in some cases one of the chains of the DNA molecule, in others – the entire DNA molecule.
19. The process of self-duplication of a DNA molecule.
1.replication 2.reparation
3. reincarnation
20. During protein biosynthesis in the cell, ATP energy:
1) consumed 2) stored
21. In the somatic cells of a multicellular organism:
1) different set of genes and proteins 2) same set of genes and proteins
3) the same set of genes, but a different set of proteins
23. Which of the processes does not occur in cells of any structure and function:
1) protein synthesis 2) metabolism 3) mitosis 4) meiosis
24. The concept of “transcription” refers to the process:
1) DNA duplication 2) mRNA synthesis on DNA
3) transfer of mRNA to ribosomes 4) creation of protein molecules on the polysome
25. A section of a DNA molecule that carries information about one protein molecule is:
1)gene 2)phenotype 3)genome 4)genotype
26. Transcription in eukaryotes occurs in:
1) cytoplasm 2) endoplasmic membrane 3) lysosomes 4) nucleus
27. Protein synthesis occurs in:
1) granular endoplasmic reticulum
2) smooth endoplasmic reticulum 3) nucleus 4) lysosomes
28. One amino acid is encoded:
1) four nucleotides 2) two nucleotides
29. A triplet of ATC nucleotides in a DNA molecule will correspond to a codon of an mRNA molecule:
1) TAG 2) UAG 3) UTC 4) TsAU
30. Punctuation marks of the genetic code:
1. encode certain proteins 2. trigger protein synthesis
3. stop protein synthesis
31. The process of self-duplication of a DNA molecule.
1. replication 2. reparation 3. reincarnation
32. Function of mRNA in the process of biosynthesis.
1.storage of hereditary information 2.transport of AK to ribosomes
33. The process when tRNAs bring amino acids to ribosomes.
1.transcription 2.translation 3.transformation
34. Ribosomes that synthesize the same protein molecule.
1.chromosome 2.polysome 3.megachromosome
35. The process by which amino acids form a protein molecule.
1.transcription 2.translation 3.transformation
36. Matrix synthesis reactions include...
1.DNA replication 2.transcription, translation 3.both answers are correct
37. One triplet of DNA carries information about:
1.Sequences of amino acids in a protein molecule
2.Location of a specific AK in the protein chain
3. Characteristics of a specific organism
4. Amino acid included in the protein chain
38. The gene encodes information about:
1) the structure of proteins, fats and carbohydrates 2) the primary structure of protein
3) nucleotide sequences in DNA
4) amino acid sequences in 2 or more protein molecules
39. mRNA synthesis begins with:
1) separation of DNA into two strands 2) interaction of the RNA polymerase enzyme and gene
40. Transcription occurs:
1) in the nucleus 2) on ribosomes 3) in the cytoplasm 4) on the channels of the smooth ER
41. Protein synthesis does not occur on ribosomes in:
1) tuberculosis pathogen 2) bees 3) fly agaric 4) bacteriophage
42. During translation, the matrix for assembling the polypeptide chain of a protein is:
1) both strands of DNA 2) one of the strands of the DNA molecule
3) an mRNA molecule 4) in some cases one of the DNA chains, in others – an mRNA molecule