Negative control of the lac operon. 

No lactose; repression. The lacI gene produces repressor, which binds to the operator and blocks RNA polymerase from transcribing the lac genes.

TLS Online TPP Program

#Id: 7971

#Unit 10. Ecological Principles

Osmosis is the movement of water across membranes to balance solute concentrations. Water diffuses from a solution that is hypotonic into a solution that is hypertonic

Turgor pressure is the hydrostatic pressure that increases as water enters plant cells.

TLS Online TPP Program

#Id: 7972

#Unit 10. Ecological Principles

Animal cells lack cell walls and do not experience turgor pressure.

TLS Online TPP Program

#Id: 7973

#Unit 10. Ecological Principles

Plant cell walls restrict the extent to which cells can expand, hence the pressure on the cell wall increases as more water enters the cell.

TLS Online TPP Program

#Id: 7974

#Unit 10. Ecological Principles

RWC, is a measure of turgidity and hence the water content of plants

TLS Online TPP Program

#Id: 7975

#Unit 10. Ecological Principles

In arid conditions, RWC values of less than 50% cause most plants to die

whereas values closer to 100% indicate plants are less affected by drought stress.

TLS Online TPP Program

#Id: 7976

#Unit 10. Ecological Principles

Water makes life possible, due to its

1. Thermal properties

2. Density

3. Viscosity

4. Solvent for inorganic nutrients