BIOFOUND 5.3 Osmoregulation pt. 2

MAKE SURE YOU ARE ANSWERING WITH TERM OR THE IMAGE ONES WONT MAKE SENSE

Kidney

An organ responsible for filtering blood, removing waste, and regulating water and electrolyte balance as part of osmoregulation.

Osmoregulation by the Kidney

Achieved through filtration of blood and reabsorption of water and solutes to maintain internal balance.

Renal Artery

Brings oxygenated, unfiltered blood into the kidney.

Renal Vein

Carries filtered blood away from the kidney.

Ureter

Transports urine from the kidney to the urinary bladder.

Urinary Bladder

Stores urine until it is excreted from the body

Cortex

One of the three major regions of the kidney, the outer region where filtration begins; contains renal corpuscles and convoluted tubules

Medulla

One of the three major regions of the kidney, the middle region with nephron loops and collecting ducts; key in creating a concentration gradient

Pelvis

One of the three major regions of the kidney, the central cavity where urine collects before draining into the ureter

Nephron

The functional unit of the kidney; filters blood, reabsorbs water and solutes, and forms urine.

Medullary Gradient

A concentration gradient in the medulla that allows water reabsorption from the nephron; key to urine concentration.

Renal Corpuscle

The first section of the Nephron includes the glomerulus and Bowman's capsule; filters blood to form pre-urine.

Glomerulus

A ball of capillaries where high blood pressure pushes plasma and small solutes into Bowman’s capsule.

Filtration Force in Glomerulus

Blood pressure drives filtration of water and solutes from blood into the nephron.

Blood Pressure and Kidney Function

Low blood pressure can reduce filtration rate, impairing waste removal; high pressure can damage glomeruli.

Obligatory Reabsorption

Automatic reabsorption of water and solutes in the nephron, regardless of body need; occurs in the proximal tubule and loop of Henle.

Proximal Tubule

The second section of the Nephron Reabsorbs most of the filtered water, glucose, ions, and amino acids back into the bloodstream.

Descending Limb (Loop of Henle)

Part of the third section of the Nephron, permeable to water, which exits into the medullary gradient; concentrates the filtrate

Ascending Limb (Loop of Henle)

Part of the third section of the Nephron impermeable to water; actively transports ions (Na⁺, Cl⁻) out to dilute the filtrate and maintain the gradient

Regulated Reabsorption

Controlled reabsorption based on the body’s current needs; occurs in the distal tubule and collecting duct.

Distal Tubule

The fourth section of the Nephron Reabsorbs sodium and water in response to aldosterone; increases sodium retention and potassium excretion.

Collecting Duct

The fourth section of the Nephron reabsorbs water in response to ADH (antidiuretic hormone); increases water retention and concentrates urine.

Glomerulus

1

Bowman’s Capsule

2

Renal Corpuscle

3

Proximal Tubule

4

Loop of Henle

5

Distal Tubule

6

Collecting Duct

7