* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download GENETIC CONTROL MECHANISMS AND …
Deoxyribozyme wikipedia , lookup
Saethre–Chotzen syndrome wikipedia , lookup
Nutriepigenomics wikipedia , lookup
Genetic engineering wikipedia , lookup
Primary transcript wikipedia , lookup
Population genetics wikipedia , lookup
Biology and consumer behaviour wikipedia , lookup
Cancer epigenetics wikipedia , lookup
Neuronal ceroid lipofuscinosis wikipedia , lookup
Expanded genetic code wikipedia , lookup
Polycomb Group Proteins and Cancer wikipedia , lookup
Minimal genome wikipedia , lookup
Non-coding RNA wikipedia , lookup
Designer baby wikipedia , lookup
Koinophilia wikipedia , lookup
History of genetic engineering wikipedia , lookup
Gene expression profiling wikipedia , lookup
Nucleic acid analogue wikipedia , lookup
Therapeutic gene modulation wikipedia , lookup
Epigenetics of human development wikipedia , lookup
Epigenetics of neurodegenerative diseases wikipedia , lookup
Genome evolution wikipedia , lookup
Site-specific recombinase technology wikipedia , lookup
Genome editing wikipedia , lookup
Genome (book) wikipedia , lookup
No-SCAR (Scarless Cas9 Assisted Recombineering) Genome Editing wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
Oncogenomics wikipedia , lookup
Genetic code wikipedia , lookup
Microevolution wikipedia , lookup
GENETIC CONTROL MECHANISMS AND MUTATIONS Control Mechanisms Over ______________ genes exist that code for proteins in humans Not all proteins are needed all the time in cells i.e. Insulin is only required when glucose levels are ____________ in the blood Genes that are constantly expressed are called ______________________________ Gene regulation is vital to an organism’s survival Gene Regulation Genes are controlled at 4 levels in cells: ________________________– regulates which genes are transcribed _________________________– mRNA undergoes changes in the nucleus ______________________– controls how often and how rapidly mRNA transcripts will be translated into proteins __________________________– control the rate at which a protein becomes active Regulation using Operons An operon is a ____________________________ consisting of : ____________________, a_________________ , separated by a short sequence of bases known as an ___________________ Only _________________ use operons to regulate genes and their respective products Two examples of operons are the ______ operon and the ______ operon The lac operon E. coli bacteria breaks down lactose using ___________________ enzyme ( 3 structural genes – lac Z, lac Y, and lac A) Aka: lactase Lac operon : off When lactose is absent a ________________ protein (Lac1 protein) binds to the ______________ site which blocks the RNA polymerase from binding to the ________________ thus, no galactosidase is produced Lac operon: on The presence of lactose acts as an ___________ which binds to the Lac1 protein (repressor) so it can no longer bind to the operator of the lac operon DNA _____________________ can now bind to the _____________ region and transcribe the galactosidase enzyme The trp operon: off This regulates genes for ______________ (an amino acid) production in prokaryotes The Trp-operon is repressed when _________ levels of tryptophan are present Tryptophan is a __________________ because it binds with the trp repressor protein and ________________ it The trp operon: on When levels of tryptophan drop, the repressor loses its shape and _____________ the operator RNA polymerase is free to bind to the ______________and _____________the trp operon genes Comparing lac & trp operons Lac operon is an example of enzyme _______________ Trp operon is an example of enzyme _______________ Lac operon regulates breakdown lactose by regulating the production of ____________ Trp operon regulates production of _______________ High levels of lactose _____________ the lac operon High levels of tryptophan _____________the trp operon Mutations Mutations are errors made in the ________ sequence that are _____________ Each of us have many _______________ mutations (most masked by an extra copy of each gene) If humans were _______________ , much of the world’s population would die due to these mutations Types of Mutations There are 2 categories of mutations: ___________________ – mutations specific to one base pair __________________________ – mutations involving large segments of chromosomes Point Mutations Silent mutations: result in no change in the ________________________ and therefore do not cause any phenotypic change (recall the redundancy in the genetic code eg. UUU & UUC code for phe) __________________ : arises when a change in the base sequence of DNA alters a codon, leading to a ______________ amino acid being placed in the protein sequence. Nonsense mutation: converts a codon specifying an amino acid to a _______ codon. Nonsense mutations are often lethal to the cell as proteins produced are ____________ ________________ : replacement of one base pair with another (missense and nonsense mutations) Deletion: elimination of a _____________ ______________ : addition of a base pair Frameshift mutation: deletion and insertion of one or two bases can cause a change in the ___________________ of a gene A change in three bases will only affect _______ amino acid in the protein (less serious) Chromosomal Mutations ___________________________________ are affected These generally occur during ________________________ ___________________ : relocation of groups of base pairs from one part of the genome to another (some types of leukemia are associated with translocations) Other mutations include______________ , ________________, _____________, and _________________ Cells may contain extra or missing chromosomes due to __________________ A _________________ means one less chromosome (ie. Turner’s syndrome) A ______________ means an extra chromsome (ie. Down’s syndrome) Causes of Mutations __________________________: caused by error in DNA replication _______________________: caused by a mutagenic agent like UV radiation, cosmic rays, X rays and certain chemicals (ie pesticides like DDT) _____________ and ____________________are all the result of genetic mutations Review 1. What are “housekeeping genes”? 2. Give three components of operons 3. How does the presence of lactose affect the lac operon of E. coli? 4. What affect does tryptophan have on the trp operon? 5. Why is a frameshift mutation more harmful than a missense mutation? 6. What kind of mutations involves large segments of DNA being altered? 7. Give some mutagenic agents