N2 constitutes about 80% of the earth’s atmosphere, but the stability of its triple bond renders it inert and metabolically inaccessible to most organisms.

TLS Online TPP Program

#Id: 9266

#XL - Q Biochemistry

N2 constitutes about 80% of the earth’s atmosphere, but the stability of its triple bond renders it inert and metabolically inaccessible to most organisms.

TLS Online TPP Program

#Id: 9266

#XL - S Microbiology

N2 constitutes about 80% of the earth’s atmosphere, but the stability of its triple bond renders it inert and metabolically inaccessible to most organisms.

TLS Online TPP Program

#Id: 9297

#XL - S Microbiology

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.

TLS Online TPP Program

#Id: 9298

#XL - S Microbiology

A.  Chloroplasts

TLS Online TPP Program

#Id: 9872

#XL - T Zoology

Innate immunity is the most ancient form of defense, found in all multicellular plants and animals.

TLS Online TPP Program

#Id: 9873

#XL - T Zoology

TLS Online TPP Program

#Id: 9874

#XL - T Zoology

The innate immune system includes physical and chemical—as well as cellular responses

TLS Online TPP Program

#Id: 9875

#XL - T Zoology

The main physical barriers—the body’s first line of defense—are the epithelial layers of the skin and of the mucosal and glandular tissue surfaces connected to the body’s openings