Dosage compensation leads to a variety of interesting coat color patterns in certain mammals. For instance, a female cat that is heterozygous for two coat color alleles, say black and orange, will usually have the "calico" or mosaic phenotype
Describe the chromosomal basis for the mosaicism (calico) in the female. Explain why chromosomally normal male cats do not show the mosaic phenotype, but XXY male cats can be calico.
Because of dosage compensation, one of the X chromosomes randomly "turns off" early in development. Once such a chromosome is inactivated, it remains so in daughter cells. Recessive alleles on the remaining active X chromosome are expressed because their normal allele (on the inactive X chromosome) is not capable of expression. Because males typically have only one X chromosome, X chromosome inactivation does not occur; however, in XXY males that are heterozygous for certain coat color genes, such inactivation and mosaicism are possible.
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c. Able to uptake large amounts of contaminants d. None of these choices. e. Grow rapidly
What does the data analysis allow you to conclude about linkage between sn and car? (Select all that apply.)
In Drosophila, singed bristles (sn) and carnation eyes (car) are both caused by recessive X-linked alleles. The wild-type alleles (sn+ and car+) are responsible for straight bristles and red eyes, respectively. A sn car female is mated to a sn+car+ male and the F1 progeny are interbred. The F2 are distributed as follows:
A) There is a high probability that the deviations from the expected number of F2 in each genotype class are due to chance.
B) The data do not allow rejection of the null hypothesis.
C) The p value is high meaning that the data is significant.
D) There is good evidence that cn and car are linked.
The integration site for sensory and motor information in humans is the
A. basal nuclei. B. cerebellum. C. thalamus. D. cerebral cortex. E. hippocampus.
The inferior vena cava transports blood to the left atrium
____________________ Indicate whether the statement is true or false.