IgA is the principal class in secretions, the most important being those from the epithelia lining the intestinal and respiratory tracts.

Dimeric IgA operates mainly on epithelial surfaces.

This monomeric IgA is predominantly of the subclass IgA1; the ratio of IgA1 to IgA2 in the blood is 10:1.

IgA antibodies produced by plasma cells in the gut are dimeric and predominantly of subclass IgA2; the ratio of IgA2 to IgA1 in the gut is 3:2.

TLS Online TPP Program

#Id: 4027

#Unit 7. System Physiology – Animal

TLS Online TPP Program

#Id: 7292

#Unit 6. System Physiology – Plant

C4 leaf has two distinct chloroplast-containing cell types: mesophyll and bundle sheath (or Kranz, German for “wreath”) cells

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#Id: 4950

#Unit 6. System Physiology – Plant

PHYA is the only gene that encodes a Type I phytochrome. Phytochrome A predominantly perceives far-red light.

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#Id: 708

#Unit 3. Fundamental Processes

seqA is part of a negative regulatory circuit that prevents origins from being remethylated.

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#Id: 7277

#Unit 6. System Physiology – Plant