Density-dependent factors affect population size in relation to the population’s density.

Density-dependent factors down into two categories. 

Negative density dependence 

Positive density dependence (inverse density dependence

TLS Online TPP Program

#Id: 5532

#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: 5533

#Unit 7. System Physiology – Animal

Descending part of the thin segment is highly permeable to water and moderately permeable to most Solutes (urea and sodium)

TLS Online TPP Program

#Id: 5534

#Unit 7. System Physiology – Animal

Descending limb of the loop of Henle is permeable to water, due to the presence of aquaporin-1 in both the apical and basolateral membranes

TLS Online TPP Program

#Id: 5535

#Unit 7. System Physiology – Animal

The ascending limb, both the thin & the thick segments is virtually impermeable to water, a characteristic that is important for concentrating the urine.

TLS Online TPP Program

#Id: 5536

#Unit 7. System Physiology – Animal

The thin segment of the ascending limb has a much lower reabsorptive capacity than does the thick segment.

TLS Online TPP Program

#Id: 5537

#Unit 7. System Physiology – Animal

Thick segment of the ascending limb of loop of Henle, has thick epithelial cells that have high metabolic activity and are capable of active reabsorption of sodium, chloride, and potassium