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91 Cards in this Set
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- Back
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What are the three recent waves of technological changes between 1775 and 1914? |
The industrial revolution and the development of the steam engines and related technologies • Rise of factories and possibilities of mass production • Railways • Cost of goods went down as shipping and production went down
Ocean streamers and globalization • Global trade increased • Suez and Panama canals (1869 & 1914 respectively) completed which let them cut through canals instead of going around
Electrification and the internal combustion engine • Industry and cities had easily accessible source of energy • Development of the incandescent light bulb and Edison's light bulb • Move from steam to combustion: from coal to oil & natural gas • Converting atmospheric nitrogen to ammonia for fertilization (fossil fuels were a critical source of energy for the process) |
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According to Jared Diamond, the six main obstacles to successful domestication are: |
1) A diet not easily supplied by humans (hence, no domestic anteaters)
2) Slow growth rate and long birth spacing (e.g. elephants and gorillas)
3) Nasty disposition (e.g. grizzly bears and rhinoceroses)
4) Reluctance to breed in captivity (e.g. pandas and cheetahs)
5) Lack of follow-the-leader dominance hierarchies (e.g. bighorn sheep and antelope) • No hierarchical structure, animal cannot follow structure/be domesticated, animals need follow-the-leader structure in the herd
6) Tendency to panic in enclosures or when faced with predators (e.g. gazelles and deer, except reindeer)
The significant six (chicken, cow, goat, horse, pig and sheep) pass all the tests |
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What is Stage 1 of Stages of Domestication? |
• Results of good fortune
• Small sub-population of wild animals remained close to human habitation (humans begin feed, climate change, selection begins)
• These animals would possess some of the requisite behavioural characteristics that make co-habitation with humans successful
• Creates the required conditions for speciation (i.e. formation of new species through genetic divergence from a common ancestor) -Essential element: genetic isolation of sub-population
• Once isolated, either the sub-population will go extinct, or natural selection in consort with genetic changes will result in genetic divergence of the sub-population from the original population |
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What is allopatric speciation? |
Original wild population moves to a distant location and a sub-population remains near a human settlement |
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What is sympatric speciation? |
Sub-population of animals with behavioural traits that make association with humans highly probably intrabreed far more frequently than interbreed |
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What is Stage 2 of Stages of Domestication? |
Reinforcement of initial isolation by providing a new environment of co-habitation and, consequently, co-evolution (consequence is a gene pool of both animals and humans changing)
Humans provide animals with food, shelter and/or protection
In turn, they use them for tasks, food and/or materials |
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What are the three consequences for humans with domestication? |
1) Genetic change • Evolution of lactose tolerance in adults, evolution of allozymes of alcohol metabolism, adaptation to a diet higher in simple carbohydrates, saturated fats and calories, etc.
2) Demographics • Dramatic increase in population
3) Infectious Diseases • Human infectious diseases have, and continue to, increase in number and the pathogens continually evolve • Continual immune adaptations of humans to animals • Mad cow is an example of being transmitted from animal to humans Two important factors: I. Population density arising from domestication (a function of domestication, people can live in cities and be fed, food can be farmed and transported to cities) II. Close proximity to, and interaction with, animals, which provide reservoirs for multiplication and evolution of infectious agents |
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What is Stage 3 of Stages of Domestication? |
Conscious human control over animal movement, mating and some behaviours
This ensures continued isolation through human captivity and human control of breeding (thought not yet directional selection) |
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What is Stage 4 of Stages of Domestication? |
Animals already intimately linked to human communities were artificially selected and mated based on desirable traits (this become directional selection)
Plants also are selection and hybridised (hybridised means you only bred true in 50% of the situations) |
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In the 20th century, what major medical biotechnology discovery was there? |
In 1929, Alexander Fleming discovered that the fungus Penicillium notatum produced a substance that could destroy or inactive a wide range of bacteria
Work by Fleming lead to the discovery and purification of the antibiotic penicillin which, in 1940s, became widely available for medicinal use to treats bacterial infections in humans |
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What is the definition of biotechnology? |
Commercial use of naturally occurring or human-digested organisms (which includes viruses) or parts thereof, to produce a product or to affect a change in some other organism or material - all intended to benefit of humans |
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What is selective breeding? |
When an organism with desirable features are purposely mated to produce offspring with same desirable characteristics |
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What is genetic engineering? |
Manipulating the DNA of an organism
Able to combine DNA from different sources |
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What is recombinant DNA technology? |
Used to produce many proteins of medical importance, including insulin, human growth hormone and blood-clotting factors
Has dominated many important areas of biotechnology |
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What is bioinformatics? |
Process using computer science in sophisticated ways to study the sequence of a gene and analyze the structure of the protein produced by the gene |
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What is the first biotech company? |
Genentech
1982, California biotechnology company and widely regarded as the world's first biotech company, received approval for recombinant insulin, used for treatment of diabetes as the first biotechnology product for human benefit |
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What are recombinant proteins? |
Widely used products of biotechnology, they are proteins created by gene cloning
Majority of these proteins are produced from human genes inserted into bacteria to make the recombinant proteins used to treat human disease conditions |
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What is gene therapy? |
Use of therapeutic genes to treat or cure a disease process; also refers to the delivery of genes to improve a person's health
Involve replacing or augmenting defective genes with normal copies of them |
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What are the types of biotechnology? |
Microbioal biotechnology • By manipulating microorganism such as bacteria and yeast, microbial biotechnology has created better enzymes and organisms for making many foods, simplifying manufacturing and production process and making decontamination process for the removal of industrial waste products more efficient • Microbes are used to make vaccines and to clone and produce batch amounts of important proteins used in human medicine, including insulin and growth hormone
Agriculture biotechnology • Use of plants as sources of pharmaceutical product
Animal biotechnology
Forensic biotechnology • DNA finger printing -Collection of methods for detecting an organisms unique DNA pattern
Bioremediation • Use of biotechnology to process and degrade a variety of natural and human-made substances, particularly those that contribute to environmental pollution
Aquatic biotechnology • Bioprospecting efforts are ongoing around the world to identify aquatic organism with novel properties that may be exploited for commercial process
Medical biotechnology • From preventive medicine to the diagnosis of health and illness to the treatment of human disease conditions, medical biotechnology has resulted in an amazing array of applications designed to improve human health • Gene therapy approaches, in which genetic disease conditions can be treated by inserting normal genes into a patient or replacing diseased genes with normal genes, are being pioneered |
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What are SNPs? |
Single nucleotide polymorphisms
SNPs are single nucleotide changes or mutations in DNA sequences that vary from individual to individual Subtle changes represent one of the most common examples of genetic variation in humans Cause of some genetic diseases, such as sickle cell anemia Testing one's DNA for different SNPs is one way to identify the disease genes that a person may be carrying
One way to do this is to isolate DNA from small amount of patient's blood and then apply this sample to a DNA microarray, also called a gene chip Microarrays contain thousands of DNA sequences Using sophisticated computer analysis, scientists can compare patterns of DNA binding between a patient's DNA and the DNA on the microarray to reveal a patient's SNP patterns |
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What is pharmacogenomics? |
Using his or her genetic information to determine the most effective and specific treatment approach |
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What is metabolomics? |
• Biochemical snapshot of the small molecule - such as glucose, cholesterol, ATP and signaling molecules that result from a cellular change - produced during cellular metabolism
• Estimates of number of human metabolites is between 2000 and 10000 have been published |
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What is stem cell technology? |
Powerful tool for treating and curing diseases
Are immature cells that can grow and divide to produce different type of cells, such as skin, kidney, and blood cells
Obtained from embryos (embryonic stem cells, or ESCs)
Also can be isolated from adult tissues (adult-derived stem cells, or ASCs)
Induced pluripotent stem cells (iPSCs) • Eventually be a great source of stem cells that can be acquired without destroying an embryo
Regenerative medicine • Phrase used to describe growing skin cells, blood cells and even whole organs in the lab and using these to replace damaged tissue or failing organs such as liver, pancreas and retina |
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What is the difference between biotechnology company and pharmaceutical company? |
Pharmaceutical company: • Involved in drug development by chemically synthesizing or purifying compounds used to make the drug - products such as aspirin, antacids and cold medicines • Typically do not use living organism to grow or produce a product (such as recombinant protein) as is the focus of biotechnology companies
Biotechnology company: • Vary in size from small companies of less than 50 employees to large companies with over 300 employees • Many start as a small start-up company formed by a small team of scientists who believe that they might have a promising product to make • Venture capital (VC) funds provided at an early stage to a start-up companies with a potential for success • Make money by owning equity in start-up companies that have a promising technology to develop • Bringing a product close to the market ultimately creates a value for a company, which may enable it to file for an IPO (initial public offering) which means that it is available for public to purchase shares of the company stock |
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What is scale-up process? |
Industrial implementation of processes in which chemical or microbiological conversion of material takes place that behave differently on a small scale (in laboratories or pilot plants and on a large scale (in production) Cultured cells making up a product must be grown on a lager scale |
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What is the difference between a prokaryotic cell and eukaryotic cell? |
Prokaryotic cell: • Prokaryotic cells or prokaryotes, do not have a nucleus, an organelle that contains DNA in animal and plants cells • They are eubacteria or cyanobacteria (archaea)
Eukaryotic cells: • They contain a membrane-enclosed nucleus and many organelles |
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What is a plasma membrane? |
Plasma membrane is a fluid, highly dynamic, complex double-layered barrier composed of lipids, proteins and carbohydrates
Performs essential roles in cell adhesion, cell-to-cell communication and cell shape Essential for transporting molecules into and out of cell Serves as a selectively permeable barrier because it contains proteins involved in complex transport processes that control which molecules can enter and leave the cell |
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What is ATP? |
Adenosine triphosphate
Energy in a form of a molecule |
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What is cytosol? |
A nutrient-rich, gel-like fluid and consists of man organelles in the cytoplasm of the eukaryotes (prokaryotes also have this) |
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What is a lysosome? |
Breaks down foreign materials and old organelles Site of intracellular digestion |
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What is a mitochondria? |
Site of adenosine triphosphate (ATP) synthesis; powerhouse of the cell |
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What is a ribosome? |
Site of protein synthesis |
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What is a rough endoplasmic reticulum? |
Sugar groups are attached to proteins within the cisternae Proteins are bound in vesicles for transport to the Golgi apparatus and other sites External face synthesizes phospholipids and cholesterol |
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What is a smooth endoplasmic reticulum? |
Site of lipid and steroid synthesis, lipid metabolism and drug detoxification |
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What is the golgi apparatus? |
Packages, modifies and segregates proteins for secretion from the cell, inclusion in lysosome and incorporation into the plasma membrane |
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What are peroxisomes? |
Enzymes detoxify a number of toxic substances Can catalase and breaks down hydrogen peroxide |
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What are microtubules? |
Support the cell and give it shape; involved in intracellular and cellular movements; form centrioles |
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What are microfilaments? |
Involved in muscle contraction and other types of intracellular movement |
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What are intermediate filaments? |
Stable cytoskeletal elements resist mechanical forces acting on the cell |
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What are centrioles? |
Organize a microtubule network during mitosis to form the spindle Form the bases of cilia and flagella |
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What are cilia? |
Move in unison, creating a unidirectional current that propels substances across cell surfaces |
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What are flagella? |
Propels the cell |
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What are nucleus? |
Controls centre of the cell; responsible for transmitting genetic information and providing the instructions for protein synthesis |
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What are nuclear envelop? |
Separates the nucleoplasm from the cytoplasm and regulates the passage of substances to and from the nucleus |
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What is the nucleoli? |
Site of ribosome subunit manufacture |
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What are central vacuole? |
Plant cells Used to store ions, waste products, pigments, protective compounds |
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What are chloroplasts? |
Plant cells Site of photosynthesis |
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What are proteases? |
Purified nuclein from white blood cells that can be broken down (degraded) by this protein-digesting enzyme |
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What was Griffith's transformation experiment? |
Worked with a strain of S. pneumoniae
Experiment provide evidence that the genetic material from heat-killed S cells had transformed (changed) or converted R cells into S cells
Heat treatment broke open S cells, which released their DNA into the tube where the living R cells took up the S cell DNA which transformed the properties of the R cells so that they became virulent, resembling S cells |
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What are the building blocks of DNA? |
The nucleotide
Each nucleotide is composed of a five carbon pentose sugar called a deoxyribose, a phosphate molecule and a nitrogenous base (adenine, thymine, guanine, or cytosine) |
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What is a gene? |
A gene is a sequence of nucleotides that provide cells with the instructions to synthesize a specific protein or a particular type of RNA |
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What are sister chromatids? |
Each chromosome consists of two thin, rod-like structures of DNA
Exact replicas of each other
During cell division, sister chromatids are separated so that newly forming cells receive the same amount of DNA as the original cell from which they arose |
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What are centromere? |
A constricted region of the chromosome consisting of intertwined DNA and proteins that join the two sister chromatids to each other
Each sister chromatid into two arms, short arm called the p arm and a long arm called the q arm |
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What is a telomere? |
Highly conserved repetitive sequences of nucleotides that are important for attaching chromosomes to nuclear envelope
Change in length believed to play a role in the aging process and in development of certain types of cancer |
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What is karyotype analysis? |
In karyotype analysis, cells are spread on a microscope slide and then treated with chemicals to release and stain the chromosomes |
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What is G-banding? |
Chromosomes are treated with a DNA-binding dye called Giemsa stain which creates a series of alternating light and dark bands in stained chromosomes
Each stained chromosomes shows a unique and reproducible banding pattern that can be used to identify different chromosomes |
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What are spectral karyotyping? |
Incorporates specific probes and techniques to colorize chromosomes it provides a more detailed analysis of chromosome structure than traditional karyotypes |
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What is mitosis? |
Somatic cells divide by a process called mitosis
Wherein one cell divides to produce daughter cells, each of which contains identical copy of DNA of the original (parent) cell |
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What is meiosis? |
Gametes formation wherein a parent cell divides to create up to four daughter cells which be either sperm or egg cells
During meiosis the chromosome number in daughter cells is cut in half to the haploid number
Sperm and egg cells each contain a single set of 23 chromosomes |
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How does DNA replication happen? |
Replication occurs through a process called semiconservative replication
DNA pulled apart and play a role as a template for copying the DNA
Replication is initiated by DNA helicase, an enzyme that separates the two strands of nucleotides by breaking hydrogen bonds between complementary base pairs
Single-strand binding proteins attach to each strand and prevent them from base pairing and reforming a double helix
Strand separation occurs at a site called the origin of replication
RNA primers, a sequence of short RNA approximately 10 to 15 nucleotides long, are synthesized by an enzyme called primase
DNA polymerase binds, a key enzymes that synthesize new strands of DNA
DNA polymerase III binds to each single strand, moving along the strand and using it as a template to copy a new strand in the 5'-to-3' direction on the leading strand (continuous fashion)
On the lagging strand, discontinuous fashion of DNA polymerased as it must wait for replication fork to open • Short strands called Okazaki fragments are synthesized • Covalent bonds between Okazaki fragments are formed by DNA ligase to ensure that there are no gaps in phosphodiester backbones • RNA primers are removed and these gaps are filled by DNA polymerase |
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What is mRNA? |
Messenger RNA
mRNA molecules, which are exact copies of genes, contain information that is deciphered into instructions for making a protein through a process known as translation
Copy of a gene
Acts as a messenger by carrying the genetic doe, encoded by DNA, from the nucleus to the cytoplasm, where this information can be read to produce a protein
Vary in length from ~1000 to several thousand nucleotides |
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What is transcription? |
RNA polymerase is a key enzyme for transcription
RNA polymerase unwinds the DNA helix and then copies one strand of DNA into RNA
Occurs in segments of chromosomes that contain genes • Presence of promoter determines which strand of DNA will be transcribed
In 5'-to-3' direction
When RNA polymerase reaches end of a gene, it encounters a termination sequence Adjacent to most genes is a promoter, specific sequences of nucleotide that allow RNA polymerase to bind at specific locations next to genes • These sequences bind either specific proteins or base pairs to create loops at the end of the RNA
Multiple copies of mRNA are transcribed from each gene during transcription
Proteins called transcription factors help RNA polymerase find the promoter and bind to DNA; sequences called enhancers call also play important roles in transcription
After RNA polymerase binds to a promoter, it unwinds a region of DNA to separate the two strands where only the template strand is copied by RNA polymerase
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What is mRNA processing? |
Primary transcript (pre-mRNA)
Initial mRNA copied from a gene
Immature and not fully functional
One is RNA splicing • Introns = stretches of DNA that do not contain protein-coding information • Interspersed between exons, protein coding sequences of a gene
Before mRNA can be used to make a protein, exons must be spliced together
Splicing provides flexibility in types of proteins that can ultimately be produced from a single gene |
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What is alternative splicing? |
Splicing can sometime join together certain exons and cut out other exons, essentially treating them as introns
Creates multiple mRNAs of different sizes from same gene
Each mRNA can then be used to produce different proteins with different, sometimes, unique functions |
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What is polyadenlyation? |
String of adenine nucleotides around 100 to 300 nucleotides in length is added to the 3' end of the mRNA creating a poly(A) "tail"
This tail protects mRNA from RNA-degrading enzymes in the cytoplasm, increasing its stability and availability for translation |
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What is rRNA? |
Ribosomal RNA
Short single-stranded molecules around 1500-4700 nucleotides long
Ribosomes Recognize and bind to mRNA and read the mRNA during translation |
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What is tRNA? |
Transfer RNA
Molecules that transport amino acids to the ribosome during protein synthesis
~75 to 90 nucleotides |
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How does the ribosome work during translation? |
Ribosomes are complex structures consisting of aggregates of rRNA and proteins that form structures called subunits
Each ribosome contain two subunits, large and small
These subunits associate to form two groove called A (aminoacyl) site and P (peptidyl site) into which tRNA molecules can bind and an E site through which tRNA molecules leaves the ribosome
Enzymes in the cytoplasm called aminoacyl tRNA synthetases attach a single amino acid to each tRNA molecule, creating a amino acyl transfer RNA or "charged" tRNA
At opposite end of each tRNA molecule is a three-nucleotide sequence called an anticodon which are designed to complementary base pair with codons in mRNA |
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What are the stages of translation? |
Beginning of translation is called initiation • Small ribosomal subunits bind to 5' end of the mRNA molecule by recognizing the 5' cap of the mRNA • Other proteins called initiation factors involved in guiding small subunits to the mRNA • Small subunits move along the mRNA unit it encounters start codon AUG • Small subunits waits for correct tRNA, called initiator tRNA to come along which would have methionine (Met) attached to it with the anticodon UAC
Next is called elongation • Additional tRNAs enter the ribosome, one at a time, growing a polypeptide chain • After two tRNAs are attached to the ribosome, an enzyme in the ribosome called peptidyl transferase catalyzes the formation a peptide bond between the amino acids • The first amino acid would pasue in the E site then released from ribosome • Release "empty" tRNAs are recycled by the cell
Translocation • Ribosome shifts so the RNA and the growing protein move into the P site of the ribosome • tRNA with a growing polypeptide chain attached is called a peptidyl tRNA
Final stage is called termination • Stop codons do not code for an amino acid • Proteins called releasing factors interact with the stop codon to terminate translation • Ribosomal subunits come apart and release from the mRNA and newly synthesize protein released into the cell |
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What is gene expression control and what are some cues that it may respond to? |
Gene expression refers to the production of mRNA by a cell
Genes may be expressed by cells only at certain times, in response to specific cues from inside or outside the cell to make proteins as needed like temperature changes, nutrients in external environments, hormones or other complex chemical signals exchanged by cells |
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What is transcriptional regulation? |
Controlling amount of mRNA transcribed from a particular gene as a way to turn genes on or off
Common promoter sequences found upstream in eukaryotes of many genes include a TATA box, located about 30 nucleotides (-30) upstream of start site of a gene or CAAT box, location about 80 nucleotides (-80) upstream of a gene
Transcription factors are DNA-binding proteins that can bind promoters and interact with RNA polymerase to stimulate transcription of a gene
Many genes that are tightly regulated by cells also contain regulatory sequences called enhancers Usually located around 50 or more base pairs upstream of promoter or downstream of a gene Bind regulatory proteins, generally referred to as activators Activators interact with transcription factors and RNA polymerase, forming a complex that stimulates transcription of a gene |
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What is testosterone and how does its transcriptional regulation work? |
Testosterone stimulates cellular activities such as muscle and hair growth in developing boys
This hormones binds to a receptor protein inside cells
Testosterone receptor protein complex acts as an activator to bind specific enhancer element in DNA called an androgen response element (5'-TGTTCT-3')
These elements are usually found close to a promoter
Testosterone and its receptors stimulate gene expression |
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What is an operon? |
Essentially clusters of several related genes located together and controlled by a single promoter
Can be stimulated (induced) or inhibited (repressed) depending on the needs of a cell
Bacteria can use operon to tightly regulate gene expression in response to their nutrient requirements |
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What is the Lac operon? How does it work? |
Consists of three genes: • LacZ = encoding enzyme Beta-galactoside • LacY = permease • LacA = acetylase
These three enzymes are necessary for transport and breakdown of lactose by bacterial cells
Lactose is a sugar present in milk which can be transported into cells by permease and then degraded into gluce and galactose by Beta-galactoside
Lac operon is regulated by a protein called the lac repressor which is encoded by a separate gene called the LacI gene
When bacteria are grown in absence of lactose, repressor protein uses helix-turn-helix motifs to bind a sequence within the lac operon promoter called the operator • Blocking RNA polymerase from binding to the promoter and blocks transcription of the lac genes
In presence of lactose, sugars act as inducer molecules that stimulate transcription of lac operon • Lactose binds to lac repressor changing the shape of the repressor protein and preventing it from binding to the operator |
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What is siRNA? |
Short interfering RNA.
Double-stranded pieces of non-protein-coding RNA
Bind to mRNA and subsequently block or interfere with translation of bound mRNAs |
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What is miRNA? |
microRNAs
Regulatory molecules that regulate gene expression by "slicing" gene expression through blocking translation of mRNA or by causing degradation of mRNA
Produce RNA transcripts that are processed y enzymes (Drosha and Dicer) into short single stranded pieces
The bind to a complex of proteins (called RISCs) which allow them to bind to mRNA that are complementary to the miRNA sequences
Binding of mRNA to an mRNA sequence can either block translation by ribosome or trigger enzymatic degradation of an mRNA |
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What is RNAi? |
RNA interference
RNA-based mechanisms of gene silencing |
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What are mutagens? |
Mimic structures of nucleotides can mistakenly be introduced into DNA and change DNA structure |
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What are point mutations? |
Single-nucleotide changes
Commonly referred to as single-nucleotide polymorphisms (SNPs) |
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What are silent mutations? |
Has no effect on the structure and function of protein |
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What are missense mutations? |
Mutation can change a codon so that a different amino acid is coded
Can be considered silent if doesn't change protein's structure and function |
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What are nonsense mutations? |
Change codon for an amino acid into a stop codon which causes an abnormally shortened protein to be translated, usually creating a non-functional protein |
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What are frameshift mutations? |
Insertion or deletions |
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What is an epigenome? |
Refers to modifications in chromatic structure which do not involve mutations in DNA sequence
Changes can differed between cell types in the body and in normal and diseased tissues
Diet and environmental condition can influence the epigenome
Plays a major role in clarifying how patterns of gene expression can vary during embryonic development |
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What was the first animal to be domesticated? |
Dogs were likely the earliest animal to be domesticated (about 16000 years ago) |
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Who and what were the three major contributions to population genetics? |
Mendal's laws of inheritance
Darwin's theory of evolution
Hardy and Weinberg • Provided a formulation of an equilibrium state for a Mendelian population • States ratio of Mendel's factors (alleles) will remain constant in all subsequent generations after the first unless something like selection, mutation, immigration and/or emigration occurs • Equations are: p^2+pq+q^2 = A:B where p + q =1 • If allelic ratios in a population change, something must be acting in or on that population |
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What is the Epistatic effect? |
Important property of many quantitative traits is the effect of the interaction of genes that control the trait
A trait can be product of many genes without any interaction among the genes other than the additive effect they each contribute to the trait
If no epistasis occurs, the differences in organism will be additive effect of the different combinations of the alleles at each locus
If epistasis occurs, AaBb and Aabb could be different not just because Bb has different effect on trait than bb but also because bb has different effect on Aa than Bb does |
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What are the three types of quantitative traits and how are they identified? |
Threshold traits • Is either present or not present and is hence discrete
Metric traits • Traits variation is continuous - all values on a continuous scale can, in principle, be realised
Meristic traits • Trait measurement is a discrete quantity but a large number of discrete variants are possible |
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What are the five types of corn grown today? |
Pop and flint corn • Have relatively high protein content and a had rather waxy starch
Dent corn • Variety most commonly grown for animal feed • Localized deposit of soft waxy starch at the crown of the kernel
Flour corn • Little protein and mostly waxy starch, grown only by Native Americans for their own use
Indian corn • Flour and flint varieties with variegated kernels
Sweet corn • Popular as a vegetable when immature, stores more sugar than starch • Has translucent kernels and loose, wrinkled skin |
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What organelles are exclusive to plant cells? |
Vacuole
tonoplast
chloroplast
plasmodesmata
cell wall |
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What is Friedrich Miescher's experiment? |
in 1896, Friedrich Miescher identifies a substance in the nucleus of eukaryotes (nucleic) which was protease resistant which shows proteins are not source of genetic material |
