Genetics Final Exam ReviewBiotechnology1) What are restriction enzymes and what is the term for the site where they specifically cut? Also called endonucleases, they cut DNA into specific fragments at specific places called recognition sites.2) What is the natural function of restriction enzymes? What do humans use them to accomplish?They are naturally found in bacteria and their role is to protect the bacteria by cutting up any foreign viral or pathogenic DNA. Today, humans use restriction enzymes to remove certain pieces of DNA to be used in PCR, to be used to make recombinant DNA, to create fragments for gel electrophoresis3) What are the circular DNA found in bacteria called? What is special about them?Circular DNA in bacteria are called plasmids (different from bacteria nuclear DNA). Plasmids are special because they can move into and out of bacterial cells. This is how bacteria can exchange information (like resistance to antibiotics) since they do not sexually reproduce.4) What chemical helps the bacterial cell take in plasmid DNA? CaCl2, Calcium Chloride5) List all materials needed for Transformation to occur. What happens during the process of transformation?The piece of DNA or gene of interest is cut from its original DNA source using a restriction enzyme and then pasted into the plasmid (now ready to be inserted into bacteria). Before transformation, bacteria are treated with a chemical called calcium chloride, which causes water to enter into the cells and makes them swell (competent). Next plasmid DNA (containing the foreign DNA) is mixed with the competent bacteria and the solution is heated. The plasmid DNA enter the bacteria through small pores created in the cell membranes. Once in the host cell, the plasmid DNA is copied many times by the bacteria’s own DNA replication machinery.6) How do scientists create genetically engineered insulin for diabetic patients?Human insulin gene of interest is cut and joined to a plasmid. Bacteria take up these engineered plasmids from the environment and incorporate the new DNA → they can eventually begin producing insulin for diabetic patients rather than extracting insulin from other animals to use.7) Who developed PCR? What does PCR stand for?Kary Mullis → Polymerase Chain Reaction8) Outline the steps of PCR (include materials and key information).Five core ‘ingredients’-the DNA template to be copied-primers, short stretches of DNA that initiate the PCR reaction-DNA nucleotide bases-Taq polymerase enzyme-Buffer for the right conditions

1) Denaturing – when the double-stranded template DNA is heated to separate it into two single strands.

2) Annealing – when the temperature is lowered to enable the DNA primers to attach to the template DNA.

3) Extending – when the temperature is raised and the new strand of DNA is made by the Taq polymerase enzyme.

9) How is Taq Polymerase used in PCR? Where does it come from and what is special about this enzyme?It is isolated from a heat-loving bacteria that is naturally found in hot springs, so the enzyme doesn't break down at the high temperatures necessary for copying DNA using a polymerase chain reaction. At high temperatures, Taq polymerase attaches nucleotides to a DNA template, thereby copying the DNA.

It comes from Thermus aquaticus, it is special because the enzyme (protein) does not denature at high temperatures

10) What procedure separates DNA for viewing? What are its applications/uses?Gel electrophoresisIn the separation of DNA fragments for DNA fingerprinting to investigate crim e scenesTo analyze results of polymerase chain reactionIn paternity testing using DNA fingerprintingIn the study of evolutionary relationships by analyzing genetic similarity among populations or species

11) How is DNA sorted during this procedure? What medium is used for the DNA to travel down?DNA is sorted by size of fragment and charge, it moves from top (negative, like DNA) to the bottom of the gel towards the positive charge. The medium is agarose (sugar) gel.

12) Label the diagram relating to this procedure.Word Bank/Clues→ DNA fragments (bands)→ Wells (where DNA is inserted)→ Agarose Gel→ Negatively Charged End (top)→ Positively Charged End (bottom)Who is most likely NOT related to the other individuals shown here? THREE.

13) How do we construct recombinant DNA?Recombinant DNA, which is often shortened to rDNA, is an artificially made DNA strand that is formed by the combination of two or more gene sequences. This new combination may or may not occur naturally, but is engineered specifically for a purpose to be used in one of the many applications of recombinant DNA

14) Draw the difference between blunt/sticky ends. How are these different ends made?Such ends may be generated by restriction enzymes that cut the DNA – a staggered cut generates two sticky ends, while a straight cut generates blunt ends.

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15) How is golden rice made?Golden rice was created by transforming rice with beta-carotene genes (precursor to vitamin A). Daffodil and soil bacterium genes used. Golden rice is genetically modified in order to produce beta carotene, which is not normally produced in rice. Beta carotene is converted into Vitamin A when metabolized by the human body. By enriching rice with Vitamin A, more people could reduce their vitamin A deficiency and reduce the risk of diseases associated with this deficiency.

16) What does CRISPR Cas9 do? How can it treat genetic diseases?CRISPR-Cas9 is a unique technology that enables geneticists and medical researchers to edit parts of the genome by removing, adding or altering sections of the DNA Sequence. An enzyme called Cas9 acts as a pair of ‘molecular scissors’ that can cut the two strands of DNA at a specific location in the genome so that bits of DNA can then be added or removed. Remove genetic sequences that are known to cause genetic diseases.

17) What does GMO stand for? Provide an example.Genetically modified organisms. An example is the GM corn crop.

18) What is the incentive for farmers to use GMO crops?Grow more of the crop, sell more and feed more people. Faster, cheaper, more efficient, etc.

19) What is unique about Bt corn?In the case of Bt corn, the donor organism is a naturally occurring soil bacterium, Bacillus thuringiensis, and the gene of interest produces a protein that kills Lepidoptera larvae, in particular, European corn borer.

20) What GMO insect did we study to combat what virus? Explain.Mosquitos to combat Zika.

21) Describe the process of cloning. You can draw or provide a written explanation.

22) Who was the first cloned animal (name and type of animal)? Dolly, a sheep

23) What clones exist in nature amongst humans and other animals?Natural clones in humans and animals are twins

24) What is gene therapy? Provide examples.Experimental technique that involves the transplantation of normal genes into cells in place of missing or defective ones in order to correct genetic disorders (instead of drugs or chemo)→ Replacing a mutated gene that causes disease with a healthy copy of the gene.→ Inactivating, or “knocking out,” a mutated gene that is functioning improperly.→ Introducing a new gene into the body to help fight a disease.

25) Mechanisms that transport foreign DNA into a host cell are called? vectorsTwo examples are found below→ explain how they workGene gun- see image

Virus- used as vectors because they can deliver the new gene by infecting the cell. They are modified so they can't cause disease in people. Some types of virus, such as retroviruses, integrate their genetic material (including the new gene) into the human cell

Evolution (Population Genetics)1) Darwin (where he traveled, observations/evidence that lead to what theory?)An English naturalist who was born in England and traveled around the world studying the plants and organisms on various continents/in various countries. He most famously studied the galapagos islands off the coast of Ecuador (think finches and various beak sizes/shapes). His observations lead to hypotheses that eventually formed the theory of evolution

2) Define:Fitness- how well an individual can survive to reproductive age and then reproduce (more fit, greater reproduction → increased passing down of genetic information, to as many viable offspring as possible

Species- a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding

Genepool- the set of all genes/genetic information in an interbreeding population (species)

Speciation- the formation of new and distinct species through the splitting of a single lineage into two or more genetically independent ones

a) Allopatric Speciation- “other fatherland” , individuals of a species become isolated from one another (such as a continental divide, mountain range, uncrossable river) and the one species can diverge into two species that might no longer be able to interbreed

b) Sympatric Speciation- “same fatherland” that occurs without physical separation of members of the population. Members are now just reproductively isolated (in plants, for example, could be due to chromosomal differences like polyploidy).

Gene flow- also called migration — is any movement of individuals, and/or the genetic material they carry, from one population to another

Genetic drift- random changes in the frequency of alleles in a gene pool, usually of small populations.

a) Founder effect- the reduced genetic diversity that results when a population is descended from a small number of colonizing ancestors

b) Bottleneck effect- occurs when there is a disaster of some sort that reduces a population to a small handful, which rarely represents the actual genetic makeup of the initial population. This leaves smaller variation among the surviving individuals

Sexual Selection- selection arising through preference by one sex for certain characteristics in individuals of the other sex ex) colorful feathers on the male peacock, colorful feathers on the male duck

Sexual Dimorphism- the differences in appearance between males and females of the same species, such as in colour, shape, size, and structure, that are caused by the inheritance of one or the other sexual pattern in the genetic material

3) Explain Neo-Darwinism.a theory of evolution that is a synthesis of Darwin's theory in terms of natural selection and modern population genetics

4) What does prezygotic isolation mean? What does it prevent?

Anything that prevents mating and fertilization is a prezygotic mechanism

Distinguish between these examples of prezygotic isolation:

a) Mechanical- incompatibility of sexual organs. They just do not fit together.

b) Geographic- physical barriers regarding the habitat/landscape that prevent mating

c) Behavioral- Species with complex courtship rituals (breeding calls, mating dances, etc.) usually exhibit a stereotyped "give-and-take" between male and female before actual mating takes place.

d) Seasonal/Temporal- Two species whose ranges overlap have different periods of sexual activity or breeding seasons

Genetics of Immunity1) B and T cells are made in the BONE MARROW

B cells mature in the Bone MarrowT cells mature in the Thymus Gland

2) Two types of B Cells and their functions:

Plasma- type of B cells that produces antibodies

Memory- “remember” past exposures to certain antigens like viruses, usually dormant and become active when exposed to the past antigen again

Three types of T Cells and their functions:

Helper T Cell- Activates B cells to produce antibodies, helps Killer T cells develop

Killer T Cell- Attacks “bad” cells (abnormal cells, cancerous cells, infected cells)

Regulatory T Cell- Regulates immune response and stops it when it is no longer needed

3) Antigens & Antibodies for each blood type, possible donations/recipients, Rh factor

4) Draw and label antibody structure.

← 5) What are HLAs and what do they do? Based on ____ major genes.Human leukocyte antigens. Based on 6 major genes

6) What is the function of the antigen presenting cell?An antigen-presenting cell is a cell that displays antigen its surface; T cells recognize this

7) The immune system is a network of lymphatic (vessels) that transport lymph fluid to small, bean shaped structures around the body called lymph nodes. This lymph fluid is carried with white blood cells.

8) Innate immunity is known as the generalized first line of defense. What is special about it and what type of immune responses fall under this category?You are born with innate immunity → mucous membranes (physiological barriers), Phagocytosis (a macrophage engulfs a foreign particle/bacteria and destroys it), inflammatory response (swelling, redness at affected site [after a splinter for example])

9) Acquired/Adaptive immunity is far more specific. Explain this immunity and provide examples (both naturally and artificially acquired).You acquire or get this type of immunity over the course of your life.Naturally acquired immunity → mother’s antibodies that cross placenta/come from breast milk, natural exposure to a virus (your body makes antibodies and memory cells for particular virus)Artificially acquired immunity → dead/weakened form of virus given in a vaccine, already made antibody serum injected by a shot

Reproductive Technology1) What are ARTs? List examples of the ones we studied.Assisted Reproductive Technologies → IVF, ICSI, surrogate mothers, artificial insemination, etc.

2) Contrast in vitro and in vivo fertilization.In vitro fertilization takes place OUTSIDE of the bodyIn vivo (in life) takes place INSIDE of the body

3) Contrast GIFT and ZIFT.GIFT - gamete intrafallopian transfer (just transferring sperm, fertilization still happens internally and naturally)ZIFT- zygote intrafallopian transfer (transferring a zygote → already fertilized outside of body before transfer)4) Define:Infertility- inability to conceive (after 1 year of trying without contraception)

Subfertility- decreased ability to conceive

ICSI- intracytoplasmic sperm injection → one sperm is directly injected into an egg cell using a glass micropipette

Surrogate- a woman who bears a child on behalf of another woman, either from her own egg fertilized by the other woman's partner, or from the implantation in her uterus of a fertilized egg from the other woman

5) Discuss, in detail, male infertility. Provide possible causes (genetic & environmental)/treatments.

Issue Description (causes, treatment)

Oligospermia- Low sperm count genes: Y chromosome abnormalities, hormones, testicular/prostate

developmentenvironment: drugs, toxins, heat (kills)

Poor Sperm Quality- Motility: sperm can’t swim, Abnormality: sperm are abnormally shaped

genes: hormones, enzymes to harness energyenvironment: drugs, toxins, heat (mutates)

Antibodies against own sperm- Autoimmune disorder

genes: immune malfunction

6) Discuss, in detail, female infertility. Provide possible causes (genetic & environmental)/treatments.

Issue Description (causes, treatment)

Irregular Ovulation- Hormone imbalance, malfunctioning/absent ovaries or tubes

genes: hormones, thyroid problemsenvironment: birth control, stress

Physical Blockage- fibroids or endometriosis, blocked/abnormal Fallopian tubes

genes: cancer, developmental defectenvironment: cancer or infections

Vaginal Secretions- hormones or certain diseases genes: hormones, mucus, disorders, immune malfunctions

7) How & at what stage is preimplantation screening done? Why is it done?When the embryo has divided into the 8 cell stage, one cell can be taken and preimplantation screening can be done. A scientists will make a karyotype (photo showing all of the paired chromosomes) to screen for an abnormalities like trisomy 21, extra or missing sex chromosomes, etc.