Bundle: Biology: The Unity and Diversity of Life, 14th + LMS Integrated for MindTap Biology, 1 term (6 months) Printed Access Card
14th Edition
ISBN: 9781305774384
Author: Cecie Starr, Ralph Taggart, Christine Evers, Lisa Starr
Publisher: Cengage Learning
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Chapter 26, Problem 1DAA
Neanderthal Hair Color The MC1R gene regulates pigmentation in humans (Sections 14.1 and 15.1 revisited), so loss-of-function mutations in this gene affect hair and skin color. A person with two mutated alleles for this gene makes more of the reddish melanin than the brownish melanin, resulting in red hair and pale skin. DNA extracted from two Neanderthal fossils contains a mutated MC1R allele that has not yet been found in humans. To see how the Neanderthal mutation affects the function of the MC1R gene. Carles Lalueza-Fox and her team introduced the allele into cultured monkey cells (FIGURE 26.16).
FIGURE 26.16 MC1R activity in monkey cells transgenic for an unmutated MC1R gene, the Neanderthal MC1R allele, or the gene for green fluorescent protein (GFP). GFP is not related to MC1R.
1. How did MCR1 activity in monkey cells with the mutant allele differ from that in cells with the normal allele?
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Chapter 26 Solutions
Bundle: Biology: The Unity and Diversity of Life, 14th + LMS Integrated for MindTap Biology, 1 term (6 months) Printed Access Card
Ch. 26 - New World monkeys _____. a. lack a tail b. are...Ch. 26 - The closest relatives of bonobos are ________. a....Ch. 26 - Prob. 3SQCh. 26 - Neanderthal Hair Color The MC1R gene regulates...Ch. 26 - Neanderthal Hair Color The MCIR gene regulates...Ch. 26 - Neanderthal Hair Color The MCIR gene regulates...Ch. 26 - Like most mammals, a(n) __________ has a wet nose....Ch. 26 - The 3.6-million-year-old footprints left by...Ch. 26 - The position where a spinal cord enters the skull...Ch. 26 - Australopiths are__________ a. extinct b....
Ch. 26 - The oldest Homo fossils found outside of Africa...Ch. 26 - A prominent chin is typical of _______. a. Homo...Ch. 26 - Compared to modern humans, Neanderthals had a...Ch. 26 - The oldest Homo sapiens fossils were found in...Ch. 26 - __________ probably had a spoken language. a....Ch. 26 - Modem people native to __________ have a higher...Ch. 26 - Match each group with its description. ___...Ch. 26 - Place the events in order. ___ 1 (earliest) a....Ch. 26 - Male aggression is rare in bonobo society and...Ch. 26 - Think about the pattern of human dispersal. Given...
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- A molecular geneticist hopes to find a gene gene in human liver cells that codes for an important blood clotting protein. He knows that the nucleotides sequence of a small part of the gene is GTGGACTGACA. briefly explain how to obtain the desired genearrow_forwardFriedreich ataxia (FRDA) is an autosomal recessive, neurodegenerative disease that causes a lack of voluntary coordination of muscle movements. Affected individuals are homozygous for an unusually large number (expansion) of repeats of a trinucleotide sequence (GAA) in the first intron of the X25 gene. Unaffected individuals typically have between 7 and 38 repeats of the trinucleotide (GAAGAAGAAGAA…). FRDA patients have anywhere from 66 to over 1,700 repeats. To understand how the GAA trinucleotide expansion leads to FRDA, researchers looked at X25 gene expression by extracting RNA from affected and unaffected patients and doing a northern blot analysis (see the figure below): In panel “a,” the researchers used a probe to detect X25 mRNA. In panel “b,” the researchers used a probe on a duplicate of the original blot to detect human GAPDH mRNA (GAPDH is an enzyme involved in glycolysis). The sample labeled “YR” is mRNA from yeast cells that was used as a control. Explain…arrow_forwardNeed answer ASAP.arrow_forward
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