Biology

Why is having an extra chromosome 21 tolerable to the point that someone with this condition can survive to maturity? (as compared to having an extra chromosome 2 , for example)
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What is capillary action? Give examples
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is this population in hardy-weinberg equilibrium
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In watermelons, bitter fruit (B) is dominant over sweet fruit (b), and yellow spots (S) are dominant over no spots (s). The genes for these two characteristics assort independently. A homozygous plant that has bitter fruit and yellow spots is crossed with a homozygous plant that has sweet fruit and no spots. The F1 are intercrossed to produce the F2. (a) What will be the phenotypic ratio in the F2?(b) If an F1 plant is backcrossed to the bitter, yellow-spotted parent, what phenotypes andproportions are expected in the offspring?(c) If an F1 plant is backcrossed to the sweet, non-spotted parent, what phenotypes and proportionsare expected in the offspring?(d) If you testcross the F1 plant, what phenotypes and proportions are expected in the offspring?
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Large quantities of solid water are stored in the ___
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How do the chromosomes in most cells of an organism, such as the leaf cells of a plant, compare to the chromosomes in its reproductive cells, which are sperm and egg cells?
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What are Three macromolecules that can be used as an energy source?
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Many kangaroo rats live in the Sonoran desert of the southwestern United States. They have a variety of adaptations for living in the desert. Under which circumstances would would the kangaroo rats of the Sonoran desert be most likely to develop new adaptations by natural selection?
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What do you think is bigger- cells or atoms and what is your supporting evidence?
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Which event is the most likely cause for the four periods when punctuated equilibrium seems to have occurred?aatedmeteorite bombardmentstasismass extinctionglobal warmingum
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The fruit fly Drosophila melanogaster has an allele that confers resistance to DDT and similar insecticides. Laboratory strains of D. melanogaster have been established from flies collected in the wild in the 1930s (before the widespread use of insecticides) and the 1960s (after 20 years of DDT use). Lab strains established in the 1930s have no alleles for DDT resistance. In lab strains established in the 1960s, the frequency of the DDT-resistance allele is 37%. Which statement is correct? A) Alleles for DDT resistance arose by mutation during the period of DDT use because of selection for pesticide resistance. B) The evolutionary fitness associated with the heritable trait of DDT resistance changed once DDT use became widespread. C) Resistance to DDT evolved in some fruit flies in order to allow them to survive.
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What are two factor that can affect the PCB level whales
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Two linked genes, A and B, are separated by 18 cM. A man with genotype AB/ab marries a woman who is ab/ab. The mans father was AB/AB.a. What is the probability that their first child will be Ab/ab?b. What is the probability that their first two children will both be ab/ab?
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How is the temperature of a solid substance affected when it is melting?O A) It increases.OB) It decreases.O c) It stays the same.
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Which directly contribute to sea levels rising?
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Why are rapidly occurring environmental changes more likely to cause extinctions than slowly occurring changes?Slow changes allow time for adaptation.Rapid changes require little adaptation.Slow changes affect only small regions.Rapid changes have a global effect.
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A dehydration reaction starting with 3.1 g cyclohexanol produces 2.2 g cyclohexene. Calculate the theoretical yield for this reaction. Report your answer with two significant figures.
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How is sunlight the primary source of energy for your own life?
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What is one disadvantage of desalination?The process kills fish.The process uses fuel that is expensive.The process makes water that is unsafe to drink.The process is too difficult to carry out in big cities.
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A technologist in a tissue bank who performed HLA typing by DNA analysis was asked to bank all DNA extracted from specimens received in the laboratory so as to maintain the highest quality of nucleic acid for the longest period. How should the DNA be stored to satisfy this request?
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PLEASE HELP!! im despratte
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Consider the Color locus. At this locus there are two alleles - red and green. The red allele is dominant to the green allele. If the selection coefficient against the green/green homozygote is 0.30, what it the fitness of the green/green homozygote?
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Question 1 (1 point)What is the term that scientists use when comparing the properties of solids, liquids and gases?
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Consider a culture medium on which only gram-positive organisms such as Staphylococcus aureus colonies can grow due to an elevated NaCl level. A yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the pH as a result and changing the color of a pH indicator chemical. This type of medium would be referred to as a(n):______ a) enrichment culture. b) differential and enrichment culture. c) selective and differential medium. d) selective median.
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