Four classes of ATP-powered pumps:

P-class pumps

V-class pumps

F-class pumps

ABC Superfamily

TLS Online TPP Program

#Id: 3656

#Unit 3. Fundamental Processes

Certain proteins, such as the enzymes glutathione peroxidase and formate dehydrogenase, contain an unusual amino acid called selenocysteine, which is part of the catalytic center of the enzymes.

TLS Online TPP Program

#Id: 8284

#Unit 1. Molecules and their Interaction Relevant to Biology

During hydrophobic interaction, the non-polar molecules come together, releasing some of the ordered water molecules in the clathrate structure and thus increasing entropy.

This is a thermodynamically favourable process (dG < 0), even though it is endothermic (dH > 0) because more hydrogen bonds are broken than are made.

TLS Online TPP Program

#Id: 2649

#Unit 7. System Physiology – Animal

Thin descending and thin ascending segments, have thin epithelial membranes with no brush borders, few mitochondria, & minimal levels of metabolic activity.

TLS Online TPP Program

#Id: 5005

#Unit 6. System Physiology – Plant

Continuous red light absorbed by phyB stimulates de-etiolation by maintaining high levels of PfrB.

TLS Online TPP Program

#Id: 6024

#Unit 3. Fundamental Processes

DNA polymerase a is unusual because it has the ability to initiate a new strand. It is used to initiate both the leading and lagging strands. 

The enzyme exists as a complex consisting of a 180-kD catalytic (DNA polymerase) subunit, which is associated with three other subunits: the B subunit that appears necessary for assembly, and two small subunits that provide the primase (RNA polymerase) activity.  It has dual capacity to prime and extend chains, this complex is often called pol a/primase.