The photosensitive pigment in the rods is called rhodopsin (visual purple).

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#Unit 3. Fundamental Processes

ThrRS has the opposite problem: It must synthesize Thr–tRNAThr but not Val–tRNAThr. Specificity is conferred by the aminoacylation site, which contains a Zn2+ ion that is coordinated by the side chain OH group of threonine. Valine cannot coordinate the Zn2+ in this way and hence does not undergo adenylylation by ThrRS.  A separate editing site deals with misacylated Ser–tRNAThr. TyrRS distinguishes between tyrosine and phenylalanine through hydrogen missing from the repertoire are GlnRS and asparaginyl-tRNA synthetase (AsnRS). To synthesize Gln-tRNAGln and Asn-tRNAAsn, these organisms possess distinct glutamyl-tRNA synthetase (GluRS) and aspartyl-tRNA synthetase (AspRS) enzymes that are nondiscriminating (ND). GluRSND synthesizes both Glu-tRNAGlu as well as misacylated Glu-tRNAGln; AspRSND synthesizes both Asp-tRNAAsp and misacylated Asp-tRNAAsn.

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#Unit 10. Ecological Principles

Biosphere Reserves The concept of Biosphere Reserves (BR) was launched in 1975 as a part of UNESCO’s

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#Unit 11. Evolution and Behavior

Bergmann’s rule: populations in colder climates tend to have greater body mass than those

in warmer climates. This pattern is so common that it has a name.

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#Unit 3. Fundamental Processes

Deamination of cytosine creates a U-G base pair. Uracil is preferentially removed from the mismatched pair

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#Unit 4. Cell Communication and Cell Signaling

Large family of cytokines:

Interleukins

Interferons

Growth hormone

Prolactin

G-CSF

Thrombopoietin

Erythropoietin