| A | B |
|---|
| What do organisms have? | Tens of thousands of genes that determine individual traits |
| What are genes lined up on? | Chromosomes |
| Where are a thousand or more genes arranged on? | 1 Chromosome |
| What are alleles? | Alternate forms of a gen for each variation of a trait of an organism |
| Traits | Any characteristic that is inherited |
| What happens in boday cells? | Chromosomes come in pairs (Mitosis) |
| What is a diploid cell? | A cell with two of each kind of chromosome |
| What is the diploid number of chromosomes? | 2n |
| What do diploid cells contain? | Contain 2 chromosomes so there are 2 alleles for any given trait |
| What happens in organisms that produce gametes or sex cells | They have cells that contain on of each kind of chromosome |
| What is a haploid cell? | A cell that contains one of each kind of chromosome |
| What is the haploid number of chromosomes? | n |
| What do haploid cells contain? | Contains 1 chromosome so there is only 1 allele for any given trait |
| What do two chromosomes of each pair in a diploid cell help determine? | Help determine what the individual organism looks like |
| WHat are homologous chromosomes? | The paired chromosomes |
| What are homologous chromosomes not always identical? | Due to variations of alleles |
| What happens when cells divide by Mitosis? | The new cells have the exact same number and kind of chromosomes |
| What would happen if sex ells had the same number of chromosomes as a body cell would? | With each fertilization the chromosome number would double |
| What is meiosis? | A different type of cell division where gametes have half the number of chromosomes as the parents |
| What happens when sex cells combine | They'll create an offspring witht the same number of chromosomes as the parents |
| What is Meiosis 1? | Begins with one diploid (2n) cell |
| What is different between Meiosis and Mitosis | They have different things happening to the chromosomes |
| During which stage does the tetrad form? | Prophase 1 |
| What is a tetrad? | 2 homologous chromosomes, each made of 2 sister chromatids (4 total) |
| What is crossing over? | A process where chromosomes exchange genetic material |
| When can Meiosis 1 and crossing over happen and where? | Can occur at any location on a chromosome and several locations at the same time |
| How is Mitosis like Meiosis in Prophase 1? | Nuclear Membrane disappears, spindle forms, chromatin condenses into chromatids |
| How is Mitosis unlike Meiosis in Prophase 1? | Homologous chromosomes group with other homologous chromosomes to form a tetrad, a "chiasma" occurs at the point where the chromosome cross over |
| What happens in Metaphase 1? | Homologous chromosomes up at the metaphase plate, Microtubles (spindles) attach to the kinetochore or centromere |
| What happens in Anaphase 1? | Homologous chromosomes separate, sister chromatids remain attached |
| What happens in Telophase 1? | Two daughter cells are formed with each one containing only one chromosome of the homologous pair, the daughter cells are now diploid |
| Meiosis 2: | Gamete formation |
| What happens in Prophase 2? | DNA does not replicate, phophase 2 is just like mitotic prophase |
| What happens in Metaphase 2? | All of the chromosomes line up at the metaphase plate? |
| What happens in Anaphase 2? | Centromeres divide, sister chromatids migrate separtely to each pole |
| What happens in Telophase 2? | Cell division is complete, four haploid daughter cells are obtained |
| How does sex linked inheritance varies with Mendel's number of 3:1 | It does by having males a 50/50 percent chance of inheriting the characteristic on the X chromosome only |
| What sex chromosomes do females and males have? | females have xx, males have xy |
| What does the Y chromosome do? | Carries little genetic information, mainly those that contribute to male characteristics (About 87 genes total) |
| What does the X chromosome do? | The X carries a lot more genetic information (About 2000 genes total) |
| What chromosome are genes for certain traits on? | The X chromosome onl |
| Why are men more likely to inherit types of disorders? | Men only recieve one X chromosome |
| Who gives men the X chromosome? | Your mom, dad gives you the y chromsome to make you a guy |
| Why are women slightly protected from types of disorders? | Are somewhat protected since they recieve two chromosomes and are less likely to inherit these types of disorders |
| What do you think happens when they get only one defective copy of an X chromosome? | As long as you get a good X you will be fine and normal |
| What are the vast majority of affected individuals? | They are males |
| Why do affected malesnever pass the disease to their sons? | BEcause there is no male-to-male transmission of the X chromosome |
| What do affected males pass the defective X chromosome to? | To all of their daughters, who are described as carriers |
| What does carriers mean? | They carry the disease-causing allele but generally show no diease symptoms since a functional copy of the gene is present on the other chromsome |
| What do female carriers pass the defective X chromosme to? | half their sons (who are affected by the disease); half their daughters (who are therefore also carriers); other children inherit normal copy of the chromosomes |
| What is "Knight's move"? | The overall pattern of the disease is therefore characterized by the transmission of the disease from affected males to male grandchildren through carrier daughters, |
| Affected females, with two deficient X chromosomes are the rare products of a marriage between an what? | An affected male and a carrier (or affected) female |
| When solving sex- linked problems you have to determine and dowhat? | You determine which trait or distorder is dominant or recessive; set up a punnett square using XX for females and XY for males (assign alleles for X only); solve as usual, keeping in mind that the Y chromosome has no allele |
| Cystic Fybrosis | Mucus clogs airways and udct s in lungs, and other organs, life expectancy is 30 years (1:3500) |
| Albinism | lack of pigment (melanin) in skin, hair, eyes, extremes case deafness (1: 17000) |
| Phenylketonuria (PKU) | missing the enzyme to process the amino acid phenylalinine; builds in the body and causes mentail retardation (1:15000) Very easily treatable with dietary restrictions |
| Tay-Sachs disease | Lipid accumulation in the brain due to abnormal lysosomes; causes mental retardation, blindness, early death before age 5 (1:5000) where (1:300 carrer) Occurs mainly in eastern European Jews (1:27 carrier) |
| Colorblindness | the disability to percieve colors in the cones of the eyes; red/green (1:10) males and (1:100 females) |
| Duchenne Muscular Dystrophy | weakening and loss of skeletal tissue (1:3500 boys) |
| Hemophelia | Blood fails to clot after injury (1:10000) |
| What term best describes the underlying cause of hemophilia in the royal families of Europe? | Inbreeding!!!! |
| Achondroplasia | A genetic form of Dwarfism (1:30000) |
| Huntington's Disease | A wasting away of brain tissue, causes uncontrolled movements, emotional disturbances and mental deterioration; is fatal (8:100,000) |
| How can HD be a big problem? | When you pass it to your children |
| Sickle Cell Anemia | Misshapen red blood cells due to a mutation in hemoglobin the protein that carries oxygen in the blood; causes pain and damage to tissues (72,000 Us; 1:500 African American birthds, 1:1200 Hispanic births) |
| What does it mean to be condominant | Both are exposed |
| How do environmental factors causemutation? | Cause mutation via ionizing radiation, age of mother, viral infections, and chemical toxins that affec gametes |
| How does non disjunction cause disorders? | Causes it during Meiosis 1 and/or Meiosis 2 |
| How can family history cause disorders? | Can cause it of a particular disorder |
| Disruptive Genes | Inbreeding and Bottlenecks |
| Inbreeding | With close relatives increasing the probability of recessive disorders |
| Bottlenecks | With geographically isolated populations |
| Natural selection within Heterozygous condition (Lethal Alleles) | Sickle cell carrier is protected against malaria; Tay-Sachs carrier is protected against Tuberculosis; Cystic Fibrosis carrier is protected against Cholera |
| How many chromosomes, autosomes (body cells), and sex chromosomes do humans have? | 46, 22 pairs, 1 pair(XX or XY) |
| Where do you get your 46 chromosomes? | 23 are donated from each parent within gametes (egg and sperm); genes are mixed up and cut in half during the prosses of meiosis |
| Karyotype | Chromosomes can be cut up and arranged in a Karyotype; a body cell that is photographed in mitosis when chromosomes are fully condensed and easier to see; cut from photographs and arranged into pairs |
| Karyotypes and special notation | The number of chromosomes, sex chromosomes |
| What are chromosome disorders? | Humans with more or less than 46 total chromosomes tend to have serious disorders; can occur at any location among the 23 pairs of chromosomes |
| Monosomy | 1 missing chromosome |
| Trisomy | 1 extra chromosome |
| Polysomy | Several extra chromosomes |
| When do chromosomal disorders tend to be more dramatic? | When present on the autosomes versus the sex chromosomes |
| What does notation reflect? | Notation reflects the charge, there is a + or - to note wher the abnormality exists except if it is on the 23rd pair (sex) |
| Plants and chromosomes | Plants can have many extra sets of chromosomes without any problems |
| What causes chromosome disorders? | Due to a mistake in meiosis, homologous chromosomes will fail to seperate properly= disjunction; abnormal numbers of chromosomes will end up in the gametes or sex cells |
| Down syndrome or Trisomy 21 | (47, +21) birth defects, mild to severe mental retardation, deformed facial features (1:800 babies) |
| Turner's Syndrome | (45, XO) Sterile, sex organs do not develop at puberty (1:2500 females) |
| Klinefelter's Syndrome | (47, XXY) sterile, subject tends to have both stunted male yet feminine features (1:750 males); a single Y will cause male development |
| Deletion | A portion of one chromosome is lost; ex: Cri Du Chat |
| Duplicaiton | The fragment joins the homolgous chromosome, the that region is repeated; Ex: Fragile X |
| Inversion | If part of a fragment flips 180 degrees; ex: Hemophilia A |
| Translocation | A fragment of a chromosome is moved from one chromosome to another and joins a non-homologous chromosome; ex: Acute Myelogenous Leukemia |
| What are differences between chromosomal disorders and genetic disorders | chromome disorders affect whole chromosome or parts of chromosomes while genetic disorders affect small segments within a single gene or even a change (mutation) in a base pair/ nucleotide |
| What do pedigrees study? | Study how a trait is passed from one generation to the next (A family tree!) |
| What do pedigrees infer? | Infers genotypes of family members |
| Autosomes | 22 pairs of chromosomes or the sex chromosomes (X or Y) |
| Number of chromosomes | called N: either N>46>N |
| What are traits heavily influenced by? | non-genetic factors or environmental factors |
| Shapes of a pedigree | squares are male (xy) and circles are females (xx) |
| Lines of a pedigree | Horizontal lies connect breeding couples and vertical lines connect parents to children where a diagonal line means death |
| Filing of a pedigree | Shading means the individual has the triat, half shading or a dot means they carry the gene called a "carrier", and no shading means the individual does not have the trait |
| ID individuals of a pedigree | Roman numberals shown generations, and numbers assign an individual to a generation and birth order |
| How do you determine if a trait is dominant or recessive? | Every other generation=recessive; every generation=dominant |
| How do you tell if a trait is autosomal or sex linked? | Affects males and females equally=Autosomal (Aa); Affects one sex more=sex linked (XcXc) or (XcY) |
| How do you interpret a pedigree? | 1. is it dominant or recessive, 2. determine if it is autosomal or sex-linked, 3. assign genotypes to affected(shaded) individuals first, 4. assign remaining genotypes to unaffected (unshaded) individuals, 5. double check your work, does the pedigree make sense |
| if pedigree is autosomal...? | Then use 2 alleles to show inheritance (AA, Aa, or aa for example) |
| if pedigree is sex-linked | Then use 1 allele for males, two for females |
| How to construct a family pedigree | Yourself, siblings in birth order, parents, extended family members, paternal and maternal grandparents, add info, double check |
| What is the vast majority of fluid in blood called? | Plasma; contains salts and varios kinds of proteins |
| What do white blood cells do? | Fight infection |
| What do platelets do? | Help blood to clot |
| What do red cells do? | Contain hemoglobin, oxygen-binding protein; transport oxygent to, and remove carbon dioxide from, the body tissues; adults have 4-6 liters of blood |
| How did many patients died when bloody types were discovered? | Experiments with blood transfusions carried out for hundreds of years and many patients died from blood poisoning |
| What did Austrian Karl Landsteiner discover? | In 1901, discovered human blood groups; that blood clumping was an immunological reaction occuring when the receiver has antibodies against the donor blood cells |
| What did Landsteiners work make possible? | Made it possible to determine blood types and paved way for blood transfusions to be carried out safely; awarded nobel peice prize |
| What was Landsteiner involved with? | Involved in discovery of both the ABO and Rh blood groups |
| What did Charles Drew come up with? | Wrote a dissertation on "banked blood" in which he described a technique he developed for the long-term preservation of blood plasma |
| Why could blood not be stored for more than 2 days? | Because of the rapid brekadown of red blood cells; Drew discovered that by seperating plasma(the liquid part of the blood) from the whole blood (in which the red blood cells exist) via a centrifuge (spinning) and then refrigerating them separately, could be combined up to a week later for a blood transfusion |
| What else did Drew discover? | Discovered that everyone has the same type of plasma |
| What was Drew named? | When WW2 broke out, was named Supervisor of the Blood Transfusion Association for New York City and oversaw its efforts towards providing plasma to the British blood bank |
| What did Drew develop? | Developed the blood plasma bank-given him a second chance of lives to millions |
| Why are there differences in hman blood? | Due to presence or asence of carbohydrate molecules called antigens and antibodies on the cell's surface |
| Where are antigens? | Located on surface of RBC |
| Where are plasma? | located in blood plasma |
| What blood group is co-dominant? | A and B are co-dominant |
| What blood group is recessive to another blood group? | O blood is recessive to A and B |
| What blood is dominanat to another blood? | Positive blood is dominant to Negative; individuals have ifferent types and combnations of these molecules which are inherited |
| Blood Group A | Has an A antigen and a B antibody |
| Blood Group B | Has a B antigen and an A antibody |
| Blood Group AB | Has a B antigen and an A antigen |
| Blood Group O | Has an A antibody and a B antibody |
| What happens if people have the antigen? | They are called RH+ |
| What happens if people do not have the antigen? | They are called RH- |
| What happens if a person with Rh+ blood receives blood from a person with Rh- blood | Then they will recieve it without any problems |
| How many people are Rh+ and how many people are Rh-? | Rh+=85%; Rh-=15% |
| What happens if the first drop only aggultinates? | Then the person has the A antigen and likely has A blood type |
| What happens if the second drop only agglutinates? | Then the person has the B antigen and likely has B blood type |
| What happens if both drops agglutinates? | They have both antigens and thus AB blood type |
| What happens if neither drop agglutinates? | They have no antigens and thus O blood type |
| What happens if the third drop agglutinates? | Then the person has the Rh factor and is Rh+ (If it does not, then they are Rh-) |
| What blood type is the "universal Donor?" | O(-) |
| What blood type is the "Universal Recipient?" | AB(+) |
| What can agglutinated red cells do? | They can clog blood vessels and stop the circulation of the blood to various parts of the body; crack and its contents leak out of the body; RBC contain hemoglobin which becomes toxic when outside the cell- can have fatal consequences for the patient |
| What animal has the blood types A and minimal O, but never B? | Chimpanzees (no type AB) |
| What animal has the blood types B and minimal O, but never A? | Gorillas (no type AB) |
| Group O | Has an increased likelihood of developing duodenal ulcers and more likely to be killed by the plague; has more protection against syphilis and other sexually transmitted diseases including flukes and worms |
| Group A | more adapted to an agrarian (non-meat based) diet and also is associated with stomach cancer |
| Group B | More adapted to high altitude; greater fertility in women |
| Group AB | More susceptible to smallpox |
