8 DNA, genes, and proteinsynthesisExam-style questionsAQA Biology1The table shows some mRNA base sequences and the amino acid sequencesthat would be produced from them.mRNA base sequenceAmino acid sequenceAGU AGU AGU AGU AGUser-ser-ser-ser-serCAC ACA CAC ACA CAChis-thr-his-thr-hisCAA CAA CAA CAA CAAgln-gln-gln-gln-glnAAC AAC AAC AAC AACasn-asn-asn-asn-asnACC ACC ACC ACC ACCthr-thr-thr-thr-thrACA CAC ACA CAC ACAcComplete the table to show the sequence of amino acids that would beproduced from the final mRNA base sequence.d Use the information in the table to givei one sequence of DNA bases that codes for the amino acid ser(1 mark)(1 mark)iione anticodon for the amino acid ser.(1 mark)eThe genetic code is described as non-overlapping and degenerate.Explain with evidence from the table that this code is:i non-overlapping(2 marks)iidegenerate.(2 marks)AQA June 2007 Oxford University Press 2015www.oxfordsecondary.co.uk/acknowledgementsThis resource sheet may have been changed from the original1
8 DNA, genes, and proteinsynthesisExam-style questionsAQA Biology2aiState precisely where in an animal cell transcription occurs.(1 mark)iiThe table contains statements about DNA replication and transcription.Put a tick in the box if the statement is true, or a cross if the statement isnot true.StatementDNA replicationTranscriptionInvolves mRNA synthesisRequires free nucleotidesInvolves complementarybase pairing(2 marks)b A DNA molecule contains 2500 guanine bases and 3500 thymine bases.Calculate how many deoxyribose molecules it contains. Explain your answer.(2 marks)AQA January 20083The diagram below shows the structure of a tRNA molecule. Oxford University Press 2015www.oxfordsecondary.co.uk/acknowledgementsThis resource sheet may have been changed from the original2
8 DNA, genes, and proteinsynthesisExam-style questionsAQA BiologycGive two ways in which the structure of a tRNA molecule differs from that ofa DNA molecule.(2 marks)d Explain how the specific shape of the tRNA molecule shown in the diagram isdetermined by the pattern of bonding.(2 marks)eiGive the base sequence of the anticodon of this tRNA molecule.(1 mark)iiGive the base sequence of the mRNA codon that would correspond tothis anticodon.(1 mark)4aThe table below shows some of the events which take place in proteinsynthesis.AtRNA molecules bring specific amino acids to the mRNA moleculeBmRNA nucleotides join with exposed DNA bases and form a molecule of mRNACThe two strands of a DNA molecule separateDPeptide bonds form between the amino acidsEThe mRNA molecule leaves the nucleusFiA ribosome attaches to the mRNA moleculeWrite the letters in the correct order to show the sequence of eventsduring protein synthesis, starting with the earliest.(2 marks)iiGive the name of the part of a cell where C takes place.(1 mark)iii Give the letter(s) of the stages involved in translation.(1 mark) Oxford University Press 2015www.oxfordsecondary.co.uk/acknowledgementsThis resource sheet may have been changed from the original3
8 DNA, genes, and proteinsynthesisExam-style questionsAQA Biologyb The following table shows some mRNA codons and the amino acids forwhich they code.imRNA codonAmino hreonineA tRNA molecule has the anticodon UAA. Give the name of the aminoacid the tRNA molecule carries.(1 mark)iiGive the DNA base sequence that codes for threonine.(1 mark)AQA June 20045The diagram shows part of a pre-mRNA molecule.aiName the two substances that make up part X.(1 mark)iiGive the sequence of bases on the DNA strand from which this premRNA has been transcribed.(1 mark)b iGive one way in which the structure of an mRNA molecule is differentfrom the structure of a tRNA molecule.(1 mark)iiExplain the difference between pre-mRNA and mRNA.(1 mark) Oxford University Press 2015www.oxfordsecondary.co.uk/acknowledgementsThis resource sheet may have been changed from the original4
8 DNA, genes, and proteinsynthesisExam-style questionsAQA BiologycThe table shows the percentage of different bases in two pre-mRNAmolecules. The molecules were transcribed from the DNA in different parts ofa chromosome.iiiPercentage of basePart ofchromosomeAGCmiddle382024end312226UComplete the table by writing the percentage of uracil (U) in theappropriate boxes.Explain why the percentage of bases from the middle part of thechromosome and the end part are different.(1 mark)(2 marks)AQA June 20116The diagram shows the life cycle of Cabbage White Butterfly (Pieris rapae).The larval stage of this butterfly is a major pest of crops such as cabbages,cauliflower and oil seed rape. The butterfly undergoes complete metamorphosisduring its life cycle.Scientists set up experiments to look at the changes in RNA content of cellsduring different stages of the life cycle. Eggs were collected and kept in acontrolled environment at 24 C and 80% humidity with a plentiful supply of oilseed rape plants for the larval stages to feed on.c i Suggest why the temperature was controlled in the investigation.(1 mark) Oxford University Press 2015www.oxfordsecondary.co.uk/acknowledgementsThis resource sheet may have been changed from the original5
8 DNA, genes, and proteinsynthesisExam-style questionsAQA BiologyiiSuggest why high humidity is used in the investigation.(1 mark)b The larva eats voraciously but the pupa does not feed. The cells inside thepupa start to break down the larval tissues and form the adult tissues. Thelarval tissue and adult tissue contain different proteins. The genes in the cellsof the larva are the same as those in the cells of the pupa. Explain how thepupa can produce different proteins using the proteins from the larva.(3 marks)cUnder the controlled conditions the pupal stage takes 10 days. The scientiststook samples of pupae at 2 day intervals and extracted the RNA. The graphshows the mean concentration of RNA per pupa during the pupal stage.iSuggest an explanation for the change in RNA concentration during thefirst four days of the pupal stage.(2 marks)iiCalculate the percentage increase in RNA between four and eight days ofthe pupal stage. Show your working.(2 marks) Oxford University Press 2015www.oxfordsecondary.co.uk/acknowledgementsThis resource sheet may have been changed from the original6
8 DNA, genes, and proteinsynthesisExam-style questionsAQA Biologyiii Suggest an explanation for the increase in RNA between days six andeight of the pupal stage.(2 marks) Oxford University Press 2015www.oxfordsecondary.co.uk/acknowledgementsThis resource sheet may have been changed from the original7
8 DNA, genes, and protein synthesis Exam-style questions. AQA Biology . ii. Suggest why high humidity is used in theinvestigation. (1 mark) b . The larva eats voraciously but the pupa does not feed. The cells inside the pupa start to break down the larval tissues and form the adult tissues. The larval tissue and adult tissue contain different proteins. The genes in the cells of the larva are .
(A), Gossypium hirsutum L. JGI (AD1) and Gossypium barbadebse L. NAU (AD2) to Arabidopsis thaliana. Using DNA demethylase genes sequence of Arabidopsis as reference, 25 DNA demethylase genes were identified in cotton by BLAST analysis. There are 4 genes in the genome D, 5 genes in the genome A, 10 genes in the genome AD1, and 6 genes in the .
I. DNA, Chromosomes, Chromatin, and Genes DNA blueprint of life (has the instructions for making an organism) Chromatin uncoiled DNA Chromosome coiled DNA You have 46 chromosomes or 23 pairs in the nucleus of each body cell. o 23 from mom and 23 from dad Gene a segment of DNA that codes for a protein, which in turn codes for a trait (skin tone, eye color, etc); a gene is a stretch of .
1) DNA is made up of proteins that are synthesized in the cell. 2) Protein is composed of DNA that is stored in the cell. 3) DNA controls the production of protein in the cell. 4) The cell is composed only of DNA and protein. 14) The diagram below represents a portion of an organic molecule. This molecule controls cellular activity by directing the
That genes are made of DNA. THE STRUCTURE OF THE GENETIC MATERIAL 10.1 Experiments showed that DNA is the genetic material . INFORMATION FROM DNA TO RNA TO PROTEIN (Protein synthesis) 10.6 -10.16 . 10.6 The DNA genotype is expressed as proteins, which provide the molecular basis for
Eukaryotic DNA can be classified into unique sequence DNA (single copy) and repetitive sequence DNA. A. Unique DNA sequence: Are single copy genes, each encode for specific protein. There are 20.000 to 25.000 genes in the human genome, grouped into 4 categories. Approx. 5.000 genes involved in the genome
DNA to Protein: Protein Synthesis Transcription: DNA contains the code necessary for a cell to produce new protein molecules during the process of protein syn-thesis. The sequence of DNA bases determines the type and order of amino acids found
IMMUNOGLOBULIN GENES UNDERGO TWO DNA REARRANGEMENTS Generates Diversity Changes Isotype (antigen elimination) About 100 Vκ gene segments 4 J Gene Segments V . DNA-dependent protein kinase Artemis XRCC4 DNA ligase IV. 3 Figure 4-7 Initiation of V(D)J rearrangement : RAG-dependent cleavage Resolution of cleavage products: DNA non-homologous .
RNA and Protein Synthesis Genes- coded DNA instructions that control the production of proteins within the cell. – In order to decode genes, the nucleotide sequence must be copied from DNA to RNA, as RNA contains the instructions for making proteins. 3 main differences between RNA and DNA: – The sugar in RNA is ribose instead of .