Biology Exam 3

Be able to explain how sex-linked genes and traits behave and why these are examples of non-mendelian genetics
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Be able to explain how sex-linked genes and traits behave and why these are examples of non-mendelian genetics
Sex linked traits do not follow Mendel's rules. The trait is encoded by an allele on a sex chromosome X or Y Everyone is not XX or XY thus the traits do not sort independently, randomly.
Describe what a polygenic trait is and give an example that we discuss
In most cases more than one gene determines a phenotype. These are polygenic.
Be able to define transposon and to explain how they move genes. How do transposons affect human genetics?
-Are mobile genetic units first discovered in maize (corn) by Barbara McClintock.
-naturally occurring pieces of DNA flanked by genes for an enzyme that allows them to "hop" from one area of a chromosome to another.
-Repair DNA for breaks in aging cells.
Explain the process of inserting a foreign gene into a bacterial cell. Include: restriction enzymes, ligase, gel electrophoresis, plasmid and component E coli
Bacteria harbor extra chromosomal DNA called plasmids. Bacterial restriction enzymes that restrict or cut DNA were identified and purified to use in cutting DNA at defined restriction sites. Restriction enzymes plus a ligase enable the cutting and pasting (ligation) of genes into plasmids. You can visualize DNA with gel electrophoresis. insulin can be made from a plasmid carrying the insulin gene in E coli. To put a plasmid into a bacterial host the cell needs to be made component by treatment with a special buffer. Then the plasmid DNA is incubated with the
cells and is absorbed. The cells are said to be
transformed
. By growing the
cells subsequently in the presence of an antibiotic, the plasmid is maintained
in the cells.
What is a genetically modified crop? Give 2 examples of how this works.
Crop contains a gene for insect toxin.
-Bacillus thuringiensis or Bt crystal
-Glyphosate or Roundup
What are advantages and disadvantages of GM crops? Are all GM crops made for profit?
-Advantages: insecticide inside plant, once thought less herbicide needed, fewer trips on the field; saves fuel and labor.
-Disadvantages: insect pests can evolve resistance, gene transferred by pollen, potential seed monopoly, more expensive seed.
Understand what DNA sequencing is and what it provides as a result.
The sequence (order of A, T, G, C bases) of a piece of DNA can be determined very rapidly today. Purified DNA is sent to a lab and within a day the sequence is emailed back.
What does non-coding DNA do if not coding for protein? Is it really "junk"?
In 2012 ~ 20 studies were published to show that some of our unknown DNA encodes controlling elements or switches that determine when and in what cells genes are activated.
- This is a major discovery that will have significance for understanding both normal functions and diseases.
Describe why it is hard to eradicate prions. Give an example of prion disease.
composed of altered protein forms that can induce abnormal shape change in normal brain protein.They cannot be destroyed by ordinary disinfection or cooking due to the structural stability.
-Chronic Wasting Disease
-Mad Cow Disease
-Scrapie
-Kuru
-CJ vCJ (mad cow in humans)
Explain what the acellular agents, viruses and prions, are and how they function and reproduce (Note how they differ)
Viruses have a protein coat with or without membrane; Information carried by DNA or RNA. Virus binds to specific
receptor on surface of host cell. Virus needs to "hijack" a cell's enzymes to make more virus. Examples: bacteriophage, HIV, influenza. Giant mimiviruses, with 900 genes, found in oceans.
~8% human genome is viral DNA that we acquired during vertebrae evolution.
How did Zika Virus reach Brazil?Travel from French Polynesia.Understand the reading about Ebola. Answer the questions.Covid-19 and SARS-CoV-2: be able to explain it at level of info given here.Corona Virus Disease 2019 [COVID-19] SARS-CoV-2 is the name of the virus, S evere A cute R espiratory S yndrome-CoV-2 Some corona viruses cause the common cold. But the SARS-CoV are very dangerous. The first epidemic by SARS-CoV-1 was 2002-4. Bats likely reservoir in wild & spread SARS to other animals: civet for SARS -1, pangolin? for SARS-2.How does HIV cause AIDS? What are some signs and symptoms of AIDS?HIV attaches to mucosal cells, multiplies, buds out to infect dendritic cells (a white blood cell type), carried to lymph nodes, there infects CD4 Helper T cells [TH]and disrupts cellular immunity to all pathogens.Why can the human body not destroy and eliminate HIV?the virus conceals itself in lymphocytes, or white blood cells, that are intrinsically hard to kill because they are resistant to killer T cells. The antibodies cannot reach.When and where did HIV originate? Are there many cases in Minnesota?What are some high risk groups, myths and challenges of AIDS? What is AZT?Know the current hypothesis of how the first cell on earth started. Have all of the steps been demonstrated in labs?Understand the age of the earth and when various cell types began.Differentiate the 3 domains of life and know what kind of organisms in each.Be able to explain how bacteria (eubacteria) and archaea differ.Describe how bacteria reproduce and how they obtain nutrients.What are some harmful and useful things that bacteria can do for us?What trend occurred in the 20th century regarding death from bacterial disease?Understand how bacteria participate with certain plant roots to make nitrogen available to plants (nitrogen fixation)How can metagenomics help us study the bacteria that we cannot grow?Be able to explain what protists are, what they do and give a few examples. Are any of them pathogens (causing illness)?Understand what defines fungi, their ecological, medical and commercial roles.What is unusual about the makeup of the cell wall of fungi? Its digestion?How does a lichen symbiosis benefit each partner? Know what two kinds of organisms are found in a lichen.Be able to explain the causes and effects of white-nose syndrome.What is the ecological role of bats?Describe what is meant by amphibian decline and what factor(s) is/are thought to be responsible. What is the role of fungus?HALFWAY DONE WITH THE SEMESTER! WOOHOO! :)Thanks for everything you have helped me with! I really appreciate it!