front 1 Genes are expressed when- | back 1 information inside the DNA affects the cells properties and activity. |
front 2 What mediates gene expression? | back 2 RNA |
front 3 Transcription is | back 3 DNA is synthesized to make RNA |
front 4 What needs to occur so that an mRNA is produced? | back 4 a gene sequence of DNA needs to be identified |
front 5 mRNA is modified by- | back 5 RNA splicing, 5' end capping and the additions of a poly(A) tail after which the mature mRNA enters the cytoplasm |
front 6 Mature mRNA is where translation occurs, what is another reason why mature mRNA different from Pre-mRNA | back 6 Post-transcriptional modifications occur in mature mRNA and are found in the cytoplasm, ribosomes and ER |
front 7 An exon is a | back 7 coding sequence |
front 8 An intron is a | back 8 noncoding sequence |
front 9 What are the steps that mRNA undergoes before it is translated into a protein? | back 9 - 2 ends of RNA are modified - introns are removed by an enzymatically catalyzed RNA splicing action -resulting mRNA is transported from the nucleus to the cytoplasm |
front 10 what are the four distinct types of RNA? | back 10 rRNA, tRNA, mRNA, miRNA |
front 11 What is the function of rRNA? | back 11 it translates and synthesizes proteins |
front 12 What is the function of tRNA? | back 12 transfers amino acids to make proteins during translation |
front 13 What is the function of mRNA | back 13 RNA that has left the nucleus, codes for proteins |
front 14 What is the function of miRNA | back 14 regulates gene expression by blocking the translation of specific mRNAs and causing degradation. |
front 15 about 80% of total RNA in the cell is- | back 15 rRNA (associates with proteins to form ribosomes) |
front 16 types of rRNA molecules | back 16 5S, 5.8S, 18S, 28S |
front 17 The smallest RNA is | back 17 tRNA (carries approrpiate amino acids) |
front 18 About 5% of total RNA is | back 18 mRNA (carries genetic information from DNA to cytosol for translation) |
front 19 miRNA is- | back 19 encoded by genes and are single-stranded RNA molecules that are 21 to 23 nucleotides in length |
front 20 miRNA are ________________ but NOT _________________ | back 20 transcribed, translated |
front 21 miRNA functions in regulating gene expression by- | back 21 their ability to bind mRNA and to down-regulate the gene expression |
front 22 A gene is- | back 22 the minimal linear sequence of genomic nuclei acids that encodes proteins and structural RNA |
front 23 Gene sequences are written from- | back 23 5' to 3' |
front 24 Genes in eukaryotic cells are composed of - | back 24 coding exons, noncoding introns, and noncoding consensus sequences |
front 25 What is a consensus sequence? | back 25 are recognition markers and are conserved. |
front 26 introns and exons differ in- | back 26 number, size, location, and sequence from gene to gene |
front 27 noncoding regions at the 5' end to the 1st axon is referred to as- | back 27 upstream sequences |
front 28 Noncoding regions at the 3' end are termed- | back 28 downstream sequences |
front 29 What is a promoter? | back 29 DNA sequences that selected or determine the start site of RNA synthesis |
front 30 What is the TATA box | back 30 the consensus sequence for promotes that is often located 15-30 base pairs upstream from the transcription start site |
front 31 what binds to the TATA box in eukaryotic cells? | back 31 proteins known as transcription/basal factors BIND to the TATA box and facilitate binding of RNA polymerase II |
front 32 Introns always begin with _____ and end with _______ (this sequence is essential for splicing out introns out of the primary transcript) | back 32 Guaninne and Uracil; Adenine and Guanine |
front 33 RNA synthesis occurs- | back 33 in the nucleus and is catalyzed by RNA polymerase |
front 34 RNA is made of the sugar | back 34 ribose |
front 35 What is the function of RNA polymerase I | back 35 synthesizes rRNAs involved in facilitating protein synthesis by the ribosome |
front 36 RNA polymerase II is responsible for- | back 36 the synthesis of mRNA and miRNAS |
front 37 RNA polymerase III- | back 37 catalyzes the synthesis of tRNAs |
front 38 What is the coding region | back 38 a region that contains DNA sequence that is transcribed to mRNA, which is then transcribed to a protein |
front 39 What is the regulatory region? | back 39 consists of two classes of sequences -ensures basal expression -regulated expression |
front 40 What are the two components in basal promoter sequences? | back 40 proximal and distal component |
front 41 What is the proximal component | back 41 TATA box, directs RNA polymerase II to correct site |
front 42 What is the distal component? | back 42 specifies the frequency of initation (CAAT and GC) boxes |
front 43 what regulates gene expression? | back 43 enhancers and response elements |
front 44 formation of the transcription complex requires- | back 44 several proteins in addition to RNA polymerase II |
front 45 RNA polymerase is a | back 45 dna- dependent RNA polymerase and it uses its formation from DNA to synthesize a complementary sequence |
front 46 Only ____ strand of the gene is used as a template for __________ and is referred to as the ________ | back 46 one, transcription, template strand |
front 47 RNA polymerase reads DNA _____ and produces an RNA molecule complementary to it | back 47 3'-5' |
front 48 mRNA in the nucleus is NOT | back 48 functional |
front 49 mRNA in the cytoplasm is | back 49 mature |