trp operon can run even in the presence of repressor. The attenuation system permits another 10-fold control over the operon’s activity.  Thus, the combination of repression and attenuation controls the operon over a 700-fold range, from fully inactive to fully active: (70-fold [repression] X 10-fold [attenuation] = 700-fold). 

TLS Online TPP Program

#Id: 8207

#Unit 2. Cellular Organization

Anthocyanin pigments stored in vacuoles

Color the petals of many flowers so as to attract pollinating insects

TLS Online TPP Program

#Id: 8208

#Unit 2. Cellular Organization

There are 4 paths from different sources feed substances into lysosomes for digestion:

• Endocytosis

• Phagocytosis

• Macropinocytosis

• Autophagy

TLS Online TPP Program

#Id: 8209

#Unit 2. Cellular Organization

TLS Online TPP Program

#Id: 8210

#Unit 2. Cellular Organization

Autophagy (“eating oneself”)

When cells are placed under stressful conditions, they have the capacity to recycle macromolecules for use as nutrients in a process of lysosomal degradation.

TLS Online TPP Program

#Id: 8211

#Unit 2. Cellular Organization

Autophagosome, or autophagic vesicle

formation of a flattened double-membrane cup-shaped structure that envelops a region of the cytosol or an entire organelle.

TLS Online TPP Program

#Id: 8212

#Unit 2. Cellular Organization