Genetics
compulsive channel switching (i. e. channel surfing) is found to
be caused by a recessive (but highly prevalent) gene on the x
chromosome (cs). also located on the x chromosome are two
other recessive genes - one that causes an addiction to watching
football on tv (fba), and one that causes excessive
burping in public (bp). the location of these genes on the
x chromosome are 25 (cs/ cs+), 43
(fba/fba+) and 76
(bp/bp+) map units. the level of
interference over this linkage group (i. e. the coefficient of
interference) is 0.15. a normal female has the genotype
cs+fba bp+
/cs fba+bp. what is the
probability that she will produce a gamete that contains all three
recessive alleles?

Over the past 60 years, many amphibian species have experienced significant population declines and some species have become extinct. scientists suspected that local human activities such as the destruction of wetlands, regional pollution, and deforestation were the main reasons for these losses. however, research over the past 20 years reveals significant amphibian population declines in protected areas of the world, such as nature preserves and parks. these global declines suggest widespread problems including increased ultraviolet radiation, acid rain, and disease. in switzerland, for example, 14 of the 20 native amphibian species are threatened with extinction. chytridiomycosis is a fungal disease first identified in 1998 as a cause of massive amphibian deaths. in some severely impacted populations, a few individuals have survived, perhaps because of some natural resistance. if these resistant individuals continue to survive and prosper, new resistant populations might emerge. this would be an example of the founder effect artificial selection genetic drift natural selection sexual selection

92 sathe best for the question 11. most animals and plants reproduce sexually. this means that dna is passed down to new organisms from two parental organisms. which of the following is a key advantage of sexual reproduction?

Read the sentence. “yesterday we arrived late for the outdoor concert in the city gardens.” which words in the sentence are adverbs? a. late; city b. yesterday; outdoor c. yesterday; late d. outdoor; city