Unlike base excision repair, the nucleotide excision repair enzymes do not recognize any particular lesion. Rather, this system works by recognizing distortions to the shape of the double helix, such as those

caused by a thymine dimer or by the presence of a bulky chemical adduct on a base.

TLS Online TPP Program

#Id: 1262

#Unit 7. System Physiology – Animal

The adrenal cortex secretes three classes of steroid hormones:

Glucocorticoids

Mineralocorticoids

Androgens

TLS Online TPP Program

#Id: 1263

#Unit 7. System Physiology – Animal

The innermost zone of the cortex, zona reticularis, and the middle zone, zona fasciculata, synthesize and secrete glucocorticoids and adrenal androgens. 

TLS Online TPP Program

#Id: 1264

#Unit 7. System Physiology – Animal

The outermost zone, called the zona glomerulosa, secretes mineralocorticoids.

TLS Online TPP Program

#Id: 1265

#Unit 7. System Physiology – Animal

The conversion of cholesterol to pregnenolone, catalyzed by cholesterol desmolase, in mitochondria.

TLS Online TPP Program

#Id: 1266

#Unit 7. System Physiology – Animal

Zona glomerulosa cells capable of secreting significant amounts of aldosterone because they contain the enzyme aldosterone synthase.

TLS Online TPP Program

#Id: 1267

#Unit 7. System Physiology – Animal

Zona glomerulosa lacks 17α-hydroxylase.