DNA and RNA
the nucleus
Location of transcription
the nucleus
Location of translation
in the cytoplasm at a ribosome
a change in the DNA code
Prions are misfolded proteins that can cause other proteins of their type to misfold, leading to neurological conditions and disorders
In DNA, the base pairing rules are....
In RNA, the base pairing rules are...
A to T, C to G
A to U, C to G
Cells of different types will make _________ proteins
Explain your answer
Different proteins because different genes are transcribed based on the job of the cell type (intestinal cells will make different proteins than a brain cell)
Transcribe and translate this DNA sequence:
TAC CCA GGA GCT TTG ACA GGG
Transcription: AUG GGU CCU CGA AAC UGU CCC
Translation: Met—Gly—Pro—Arg—Asn—Cys—Pro
Point, insertion, deletion
List the 3 differences between DNA and RNA
RNA is single stranded, DNA is double stranded
RNA has base uracil instead of thymine in DNA
RNA has the sugar ribose, DNA has the sugar deoxyribose
The enzymes needed for transcription to occur and what they do in the process
Helicase: unzips DNA double helix, exposing the sequence to be copied
RNA polymerase: builds complementary mRNA molecule from the now exposed DNA sequence, makes the mRNA polymer
Give a potential DNA sequence for the following amino acid sequence
Met-Pro-Asp-Leu-Arg-Pro-Leu-Ser
Check answers
1 possible : TAC GGT CTA GAA TCT GGG GAG TCA (template strand)
What kinds of mutation occurred in this protein? The normal and mutated amino acid sequences are shown below:
Met-Glu-Gly-Asp-Leu-Arg-Trp-Ser
Met-Glu-Glu-Asp-Leu-Arg-Trp-Ser
missense: 3rd a.a. changed from Gly to Glu
What is sickle cell anemia and what is it caused by?
Sickle cell anemia is a blood disorder where your RBCs have shorter lifespans and the hemoglobin found within them is misshapen, leading to sickle shaped RBCs that tend to clot and clump in blood vessels.
List and describe the 3 types of RNA
mRNA: messenger RNA that is the copy of a gene from the DNA
tRNA: transfer RNAs that bring amino acids to the ribosome during translation
rRNA: ribosomal RNA makes up the ribosome
operons
Describe of tRNAs movement (after initiation) through the ribosome and how amino acids are added to the growing protein (Be specific)
tRNAs will enter the ribosome through the A site, their amino acid will be joined to the growing polypeptide in the P site, and the now empty tRNAs will leave throuhg the E site. This continues until termination
***DAILY DOUBLE****
List the effects of mutations and describe each
Silent, missense, nonsense, frameshift
What is the function of myostatin and what will happen in cows if a mutation occurs within the gene that codes for it.
In a sentence, relate DNA and RNA to each other. Be sure to use the follwoing terms: base-pairing rules, complementary, and sequence
RNA is a copy of a sequence of DNA that is comprised of the complementary nucleotides based on base pairing rules.
***DAILY DOUBLE***
You decide to dump a glass of chocolate milk on a culture of bacteria, describe how the bacterial cultural digests the lactose in the milk starting from transcription and ending with the digestion of lactose.
Bacteria absorbs milk, cells are exposed to lactose, lactose binds to repressor protein on operator region of gene and forces it off, allowing cells to transcribe gene for lactase, many mRNA transcripts are made and sent to ribosomes. Ribosomes begin synthesis of lactase based on mRNA codes provided. Lactase is now made and begins digestion of lactose that has been taken in by cells in the cytoplasm. Lactase will eventually digest the lactose bound to the repressor protein, which will allow the repressor to bind to the operator again and block any further transcription of the gene
Describe initiation, elongation, and termination
Initiation: small ribosomal subunit recognizes start codon in mRNA and they bind together, tRNA holding Met will bind to top of mRNA strand and large ribosomal subunit will associate with the small, making the whole ribosome
Elongation: tRNAs enter through the A site, their amino acid is joined to the polypeptide at the P site, and the now empty tRNA leaves through the E site. This process continues until a stop codon is encountered.
Termination: once a stop codon enters the A site of the ribosome, a release factor will come in and bind in the A site, causing the ribosomal subunits to dissociate from each other, releasing the mRNA, the newly made protein, and any tRNAs remaining in the ribosome
Frameshifts because the entire reading frame after the insertion or deletion is altered, changing many amino acids in the sequence as a result
Nonsense mutations are also bad but not as bad because it simply results in a shorter protein, while frameshift mutations can lead to shorter or longer, nonsensical proteins that can be deleterious to the human condition.
Give 2 examples of prion caused diseases and describe them in detail
Any of the following:
Creutzfeldt-Jakob Disease (CJD)
Fatal Familial Insomnia
Bovine Spongiform Encephalopathy (BSE)
Chronic Wasting Disease (CWD)
Scrapie
Kuru