No clumping of the donor's blood is indicated by the word "None" in the green squares. None also denotes the lack of anti-A or anti-B antibodies in the type O recipient. It is clear from this chart that the "universal donor" is type O, while the "universal recipient" is type AB. If you include the Rh factor, then the universal donor becomes O Negative while the universal recipient becomes AB Positive.
Although it is much more complicated, the Rh blood factor can be explained by a pair of alleles on homologous chromosome pair 1. Like the type O gene, the recessive Rh negative gene - does not produce an antigen. Because of the time factor involved in building up a concentration titre of antibodies, the first transfusion may not cause any major problems; however, a subsequent transfusion of Rh positive blood could be very serious because the recipient will clump all of the incoming blood cells.
Based upon the above table, Rh positive recipients can theoretically receive positive or negative blood, and Rh negative donors can theoretically give to Rh positive and Rh negative recipients. The following tables explain how to calculate the answers for questions - The data in the tables is slightly different from your exam, but the method of calculation is the same. These questions refer to a cross between two hypothetical watermelons with four pairs of fruit characteristics.
In watermelons the gene for green rind G is dominant over the gene for striped rind g , and the gene for short fruit S is dominant over the gene for long fruit s. The alleles for rind color and fruit length occur on two different pairs of homologous chromosomes.
For this question, assume that a gene for large melons L and and gene for many seeds F occur at opposite ends of another chromosome linkage.
The alleles for size and seed number, i. A watermelon plant bearing large, green, short fruits containing many seeds was crossed with a plant bearing large, striped, long fruits containing many seeds. Some of the offspring from this cross produced small, striped, long fruits with few seeds.
Assuming no crossing over between homologous chromosomes , what is the fractional chance of producing the following offspring? Remember that there are three pairs of homologous chromosomes in this problem, and one of the homologous pairs exhibits autosomal linkage. The chromosomes of each parent are shown in the following illustration: There are several ways to solve this problem, but one way is to construct a 16 square checkerboard with eight rows and two columns. To the left of each row, put the eight gametes of the parental plant bearing large, green, short fruits containing many seeds.
At the top of each column, put the two gametes of the parental plant bearing large, striped, long fruits containing many seeds. The most difficult part of this problem is to figure out the exact gene combinations of the gametes. Once this is known, you can simply fill in the squares of the checkerboard with the correct gene combinations genotypes for each offspring. There a total of 12 different genotypes in the checkerboard.
The plant bearing large, striped, long fruits containing many seeds can produce only two different kinds of gametes shown in red in Table 1. The gametes must contain one of the LF or lf chromosomes, one of the g chromosomes, and one of the s chromosomes.
Therefore, the two possible gametes are: LFgs and lfgs. The LF and lf genes always appear together because they occur on the same chromosomes. Without crossing over, you could never have Lf together or lF together. The plant bearing large, green, short fruits containing many seeds can produce eight different kinds of gametes shown in green in Table 1.
The gametes must contain one of the LF or lf chromosomes, one of the G or g chromosomes, and one of the S or s chromosomes. Four of the eight gametes will contain lf plus GS, Gs, gS or gs. When all the 16 squares of the checkerboard are filled in, simply find the genotypes in the squares that are described in questions The capital letters represent dominant genes alleles while the small case letters represent recessive genes alleles.
Therefore, a plant with a genotype of LlFfGgss would produce large L , green G , long s , fruits containing many F seeds. Part V. Multiple Choice Questions - 1. Genetics Extra Credit Problems Genetics Of Triploid Watermelon Articles About Plant Genetics Hybrids In San Diego County More Hybridization In Plants Question The medical term for this maternal-fetal condition is "erythroblastosis fetalis" because of the presence of nucleated, immature RBCs called erythroblasts in the fetal circulatory system.
The fetus bone marrow releases immature erythroblasts because of the destruction of mature RBCs erythrocytes by the mother's anti-Rh antibodies. This prevents her from producing anti-Rh antibodies. In this scenario of erythroblastosis fetalis, the fetus must be Rh positive, the mother Rh negative and the father Rh positive. You can easily determine the exact genotype of the mother and fetus, but the father's genotype could be homozygous or heterozygous Rh positive.
After several days, the mother begins to produce anti-Rh antibodies. The antibodies begin clumping fetal postive RBCs. This cross involves codominance and gene interaction resulting in a phenotypic ratio of offspring. Hint: Lethal recessive genes can be carried and passed on in diploid populations without ever being expressed; however, in a haploid population, there is no dominant gene to mask the lethal recessive trait. Solid color dogs are more valuable to cocker spaniel breeders.
To test your solid color dog, you would want to breed her with a known homozygous male. Barr bodies would be of little help in this case because the alleles for solid color S and spotted s do not occur on X chromosomes. The fur coloration of calico cats is governed by two alleles black and yellow , both attached to the same loci on a homologous pair of X chromosomes. This question is explained in more detail at the following link: See Barr Bodies and Gender Verification Questions - When different species are crossed together, the result is a hybrid.
Hybrid animals are typically sterile, although they can be male or female. For information about interesting examples of hybridization, please refer to the following hyperlink: Information About Plant Hybrids: 1. Apples: Polyploid Varieties 2. Bananas: Seedless Triploids 3. Cereals: Some Polyploid Hybrids 4. Grapes: Some Seedless Cultivars 5. Sterile Hybrids Including The Mule 6. Mustard Family Vegetable Hybrids 7.
Tomatoes: Genetically Engineered 8. The answers to this questions about Barr bodies can be found at the following hyperlink: See Barr Bodies and Gender Verification Questions - The answer to this question can be found at the following hyperlink: Hybridization Between a Horse and a Donkey Question The answer to this question can be found at the following hyperlink: Generation Number n Interval of 24 years.
In a cross between two normally pigmented people who are heterozygous for albinism, the odds are that one out of four of their children will be an albino. The aa genotype is an albino. The square root of 20, is approximately With this information you can set up the following genetic checkerboard Punnett square and find the total fractional probability for heterozygous carriers of albinism. The following table illustrates these exponential numbers of zygotic combinations based upon independent assortment of genes on separate chromosomes.
If several genes alleles are linked to one pair of homologous chromosomes, then they are assorted as one pair of genes on one pair of chromosomes. Half of the gametes get a dominant A and a dominant B allele; the other half of the gametes get a recessive a and a recessive b allele. Review problem 3's tutorial if necessary. Possible gametes for each AaBb parent Since each parent has four different combinations of alleles in the gametes, there are sixteen possible combinations for this cross. Therefore we use a 4 square by 4 square Punnett Square.
How many gametes can be produced? How many gametes do humans have? What are gametes example? Is PP genotype or phenotype? How many types of gametes will be produced by a male Drosophila? Which are never hybrids? What are female gametes called?
Is a sperm a cell? How many gametes do females produce? How many chromosomes do gametes have? How many different types of gametes are formed from Aabbccdd? So, the correct answer is ' Four '. How many genetically different gametes can this male produce?
What are the different types of genes called? How many gametes are in a Trihybrid cross? How many types of gametes can be produced by a diploid organism? This website uses cookies to ensure you get the best experience on our website. More info.
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