Chemotaxis 

sperms are attracted toward eggs of their species by following a gradient of a chemical secreted by the egg.

TLS Online TPP Program

#Id: 5574

#Unit 7. System Physiology – Animal

There are four isoforms of the transport protein:  UT-A in the kidneys (UT-A1 to UT-A4) UT-B in the erythrocytes & descending limbs of the vasa recta 

TLS Online TPP Program

#Id: 5575

#Unit 7. System Physiology – Animal

Urea transporters UT-A1 and UT-A3 facilitate diffusion of urea out of the medullary collecting ducts while UT-A2 facilitates urea diffusion into the thin descending loop of Henle.

TLS Online TPP Program

#Id: 5576

#Unit 7. System Physiology – Animal

The vasa recta do not create the medullary hyperosmolarity,but they do prevent it from being dissipated

TLS Online TPP Program

#Id: 5577

#Unit 7. System Physiology – Animal

Countercurrent exchange is a passive process; it depends

on movement of water and could not maintain the osmotic gradient along the pyramids if the process of counter-current multiplication in the loops of Henle were to cease.

TLS Online TPP Program

#Id: 1195

#Unit 7. System Physiology – Animal

Female hormonal system, consists of three hierarchies of hormones:

1. GnRH

2. FSH and LH

3. Estrogen and progesterone

TLS Online TPP Program

#Id: 1196

#Unit 7. System Physiology – Animal

FSH and LH stimulate sex hormone synthesis by the activation of the cyclic adenosine monophosphate second messenger system.