#ROCKET POCKET MOUSE ANSWER KEY SKIN#
#ROCKET POCKET MOUSE ANSWER KEY CODE#

Watch the Howard Hughes Medical Institute's 10-minute film The Making of the Fittest: Natural Selection and Adaptation 2.

#ROCKET POCKET MOUSE ANSWER KEY CODE#

MATERIALS genetic code chart (see page 6 of this handout or a biology textbook) blue, red, and green colored pencils PROCEDURE 1. This results in translation being stopped before the amino acid sequence of the protein is completed. This type of mutation causes a change in the primary structure of the protein (the linear sequence of amino acids), which can result in a change in the three-dimensional conformation of the protein Nonsense mutation: This mutation causes the protein to be truncated (cut short) due to the incorporation of a 'stop' signal into the DNA sequence. Missense mutation: This mutation causes an amino acid in the sequence to be changed to another amino acid. Potential effects a gene mutation has on a protein: Silent mutation: This mutation does not cause a change in the amino acid sequence of the protein therefore, there is NO change in the resulting protein. The deletion of nucleotide(s) can result in 'frame shift' mutations. The insertion of nucleotide(s) can result in 'frame shift' mutations, Deletion mutation: the loss of one or more nucleotide(s) from the DNA geng sequence. Mutations that affect a single nucleotide are called 'point mutations.' Insertion mutation: the addition of one or more nucleotide(s) to the DNA gene sequence. Types of mutations: Substitution mutation: the replacement of one nucleotide of DNA for another. There are several types of mutations, and they affect the amino acid sequences of proteins in different ways. A change in protein structure can change, negate, or have no effect on function. Gene mutations can change the structure of the resulting protein. GENE MUTATION A gene mutation is any change in the DNA sequence of a gene. The mutated version of the Meir gene, however, triggers melanocytes to increase the production of eumelanin, resulting in the dark coat-color phenotype. The melanocytes of wild-type (nonmutant) mice produce more pheomelanin than eumelanin.

#ROCKET POCKET MOUSE ANSWER KEY SKIN#

This gene encodes a protein called the melanocortin 1 receptor (MC1R) and is found embedded in the cell membranes of melanocytes, specialized pigment-producing skin cells. The products of several genes, including the Mcir gene, control the synthesis of these pigments. Their analyses led to the discovery of a mutation in the Mcir gene that is involved in coat color determination THE MCIR GENE Two pigments primarily determine the coat color of rock pocket mice: eumelanin, which is dark-colored, and pheomelanin, which is light-colored. Researchers analyzed the data from these two populations in search of the genetic mutation responsible for the dark coat color. Scientists have collected data from a population of primarily dark-colored mice living in an area of basalt called the Pinacate lava flow in Arizona, as well as from a nearby light-colored population.

However, populations of primarily dark- colored rock pocket mice have been found living in areas where the ground is covered in a dark rock called basalt caused by geologic lava flows thousands of years ago.

Most rock pocket mice have a sandy, light-colored coat that enables them to blend in with the light color of the desert rocks and sand on which they live. INTRODUCTION THE ROCK POCKET MOUSE The rock pocket mouse, Chaetodipus intermedius, is a small, nocturnal animal found in the deserts of the southwestern United States.

Rocket pocket mouse answer key