Renal System

Caroll Bai & Brianna Estrada Period: 4 Anatomy/ Physiology

Overview

❖ Consists of the two kidneys, ureters, the bladder, and the urethra ❖ Produces, stores, and eliminates fluid waste

Structure- Kidneys

❖ ❖ ❖ ❖ Location Function Regions ➢ Renal sinus, pelvis, medulla, cortex, capsule ➢ Medulla and cortex Nephron: functional unit of a kidney

Structure- Kidney pathway

❖ Vasculature ➢ Renal arteries, abdominal ➢ aorta, interlobar arteries, arcuate arteries, afferent arterioles, glomerular capillaries, efferent arterioles, and peritubular capillaries Renal veins

Structure- Ureters

❖ Ureters ➢ Tubular organ, extends from each kidney to bladder (25 cm long) ➢ ➢ Mucous, muscular, fibrous coat Peristalsis

Structure- Bladder

❖ Bladder ➢ Trigone ➢ Inner layer- mucous coat ➢ Second layer ➢ submucous coat Third layer- muscular ➢ coat Outer layer- serous coat

Structure- Urethra

❖ Urethra ➢ Function ■ Tube that carries urine from ➢ ➢ bladder to outside of body Gender difference Urethral glands

Nephron- Renal Corpuscle

❖ Glomerulus ➢ Filters water and dissolved substances ❖ from plasma Bowman’s Capsule ➢ Receives the glomerular filtrate

Nephron- Renal Tubule

❖ ❖ ❖ Proximal convoluted tubule ➢ Tubular reabsorption Loop of Henle ➢ Descending limb ■ Reabsorption of water by osmosis ➢ Ascending limb ■ Reabsorption of metal ions by active transport Distal convoluted tubule ➢ Tubular secretion by active transport

Nephron- Collecting Duct

❖ Reabsorption of water by osmosis

Urine Creation

❖ ❖ ❖ ❖ ❖ Afferent & efferent arterioles Structures involved ➢ Nephron ➢ Glomerulus ➢ ➢ ➢ Bowman’s Capsule Loop of Henle Collecting duct Glomerular filtration Tubular reabsorption Tubular secretion

Glomerular Filtration

❖ ❖ ❖ ❖ Bowman’s Capsule Permeable capillaries (fenestrae) Filters by size of molecule Filtered ➢ ➢ ➢ H 2 O NaCl, K + , HCO 3 Glucose ➢ Amino Acids ➢ Creatinine ➢ Urea

Tubular Reabsorption

❖ ❖ Proximal convoluted tubule (but happens all throughout) Reabsorbed back into blood: ➢ K + ➢ ➢ H 2 O NaCl ➢ Amino acids ➢ ➢ HCO 3 Glucose ■ If present in urine, could indicate abnormality

Tubular Secretion

❖ ❖ Distal convoluted tubule Secreted: ➢ ➢ ➢ ➢ Uric acid K + H + Organic acids ■ Antibiotics (penicillin)

Glomerular Filtration Rate (GFR)

❖ ❖ ❖ How much blood passes through the glomeruli each minute Tests efficiency of kidneys Affected by: ➢ Filtration pressure ➢ RAAS (Renin Angiotensin Aldosterone System) ➢ ANP (Atrial Natriuretic Peptide) ■ Increases GFR ■ Increases Na + excretion

Filtration Pressure

❖ Hydrostatic Pressure ➢ Glomerular- blood ■ “Pushing” ex. ❖ ❖ balloon ➢ Capsule- filtrate ■ “Pulling” Colloid Osmotic (Oncotic) ➢ “Pulling” ex. sponge Net Pressure ➢ All pressures added together

Urine Regulation

❖ ADH ➢ Regulates water ➢ reabsorption in collecting duct Low ADH: diluted urine ➢ High ADH: concentrated urine

Urine

❖ ❖ ❖ ❖ Composition ➢ Mostly water ➢ Urea, uric acid, and creatinine ➢ Some amino acids and electrolytes Renal clearance: rate at which a chemical is removed from the plasma Insulin clearance test & creatinine clearance test Para-aminohippuric acid (PAH)

Micturition (Urinary reflex)

❖ ❖ The process or reflex or urinating Structures ➢ Bladder ➢ Micturition reflex center ➢ ➢ Detrusor muscle Internal urethral sphincter ➢ External urethral sphincter

Works Cited

"Aldosterone."

Wikipedia

. N.p., n.d. Web. 8 Apr. 2015. < http://en.wikipedia.org/wiki/Aldosterone >.

"Forces of Filtration."

YouTube

. YouTube, n.d. Web. 13 Apr. 2015. < https://www.youtube.com/watch?v=VMvD29-Agtg >.

"Glomerular Filtration Rate: MedlinePlus Medical Encyclopedia."

U.S National Library of Medicine

. U.S. National Library of Medicine, n.d. Web. 13 Apr. 2015. < http://www.nlm.nih.gov/medlineplus/ency/article/007305.htm

>.

"Nephron Function."

YouTube

. YouTube, n.d. Web. 13 Apr. 2015. < https://www.youtube.com/watch?v=vNvZaGcLzEo >.

"Renin-Angiotensin-Aldosterone System."

YouTube

. YouTube, n.d. Web. 13 Apr. 2015. < https://www.youtube.com/watch?v=PDE2qdS2ZvY >.