The 5’ cap of most mRNA is monomethylated, but some small noncoding RNAs are trimethylated.

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#Id: 9320

#Unit 4. Cell Communication and Cell Signaling

Light-triggered closing of the cGMP-gated cation

channels causes a drop in the cytosolic Ca2+ concentration inside the rod cell.

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#Id: 4735

#Unit 5. Developmental Biology

In C. elegans

When sperm fuses with the egg cell membrane, polyspermy is prevented by the rapid synthesis of chitin by the newly fertilized egg.

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#Id: 6698

#Unit 3. Fundamental Processes

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#Id: 10122

#Unit 6. System Physiology – Plant

The IAA conjugate to Asp or Glu causes irreversibly degraded to the oxIAA conjugate. IAMT1, indole-3-acetate O-methyltransferase1.

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#Id: 9297

#Unit 6. System Physiology – Plant

Nitrite reductase

Nitrite (NO2-) is a highly reactive, potentially toxic ion.

Plant cells immediately transport the nitrite into chloroplasts or plastids.

The enzyme nitrite reductase reduces nitrite to ammonium.

Leaf chloroplasts and root plastids contain different forms of nitrite reductase.

Each polypeptide contains two prosthetic groups, an iron-sulfur group and a specialized heme.

NO3-, high sucrose conc, and light induce the transcription of nitrite reductase mRNA.

Asparagine and glutamine repress the induction.