Bio 1108 Lab

Urinary System

List of StructuresKidney Model (M) and Torso (T): Kidney (M, T)Renal Artery (M, T)Renal Vein (M, T)Arcuate Blood Vessels (M)Renal cortex (M)Renal medulla (M)Renal pyramids (M)Renal papillae (M)Calyces (M)Renal pelvis (M)Ureter (M,T)Urinary bladder (T)Urethra (T)

Pyramid and Nephron Model

Kidney SlideFetal Pig• Kidney• Ureter• Urinary Bladder• Urethra, Male• Urethra, Female

Arcuate Blood VesselsBowman’s (Glomerular) Capsule GlomerulusProximal Convoluted TubuleAfferent and Efferent ArteriolesLoop of HenleDistal Convoluted TubuleCollecting Duct

GlomeruliTubules

Part 1 Gross Structures

12th Rib is the last rib which is attached to the vertebral column.It is a floating rib due to the single attachment.

Renal arteries deliver blood to the kidneys.Renal veins drain the kidneys.

The Ureters deliver urine to the urinary bladder.The urinary bladder empties the urine through the urethra.

Part 1 Gross Structures

KidneyRenal ArteryRenal Vein UreterUrinary BladderUrethra, male

Small dot

Part 1 Gross Structures

BLADDERKIDNEYURETER

Part 1 Gross Structures

RECTUMKIDNEYURETER

Part 1 Gross Structures

bladder

ovary

vagina

Urogenital sinus

Female Reproductive Organs

URETHRA

Part 1 Gross Structures

Uterine horns

BLADDERURETHRAPENISTESTES

Part 1 Gross Structures

BLADDER, Reflected craniallyURETHRA, fetal pig and dark dot

on modelPENIS, fetal pig and coronal

section on modelTESTES, on fetal pig only

Part 1 Gross Structures

Filtrate Flow:Filtrate is produced by the

nephron (unit of the kidney).

Filtrate contains water, ions, glucose, & amino acids. Temporary presence.

Renal Cortex to Renal Medulla to Calyces

In the Calyces, Filtrate is renamed urine.

Urine Flow:Urine flows from the

Calyces to the Renal Pelvis to the Ureter to the Urinary Bladder then through the Urethra to outside the body.

Part 2 Gross Structures

Part 2 Gross Structures

Renal ArteryRenal VeinRenal cortexArcuate artery and vein separate Renal Cortex from Renal MedullaRenal medullaRenal pyramidRenal papillae (end of renal pyramid & renal medulla)

Calyces

Arcuate Blood

Vessels

Renal Papillae

Filtrate flow: Renal Cortex to Renal Medulla to Calyces)

Renal

Cortex

Renal

Medulla

Part 2 Gross Structures

Renal ArteryRenal VeinRenal cortexArcuate artery and veinRenal medullaRenal pyramidRenal papillaeCalyces (has urine)Renal pelvis (has urine)Ureter (has urine)

ureter

Renal Pelvis

Calyce

Urine flow: Calyce to Renal Pelvis to Ureter

Renal Cortex contains the Glomerulus Capusules that contains the Glomerulus . The Glomerulus can be found on a model and the microscope slide material. Tubules are also present.

Renal Medulla contains tubules that convey filtrate to the Collecting Duct. The Collecting Duct empties into the Calyces which empty into the Renal Pelvis.The Glomerulus and tubules form the Nephron.

Part 2 Gross Structures: Renal Pyramid & Nephron Model

The Nephron is found in both the Renal Cortex and Renal Medulla

The Flow of the Filtrate:The Filtrate is created when blood passes through the Glomerulus. The blood pressure forces water containing ions and small molecules to enter the capsule of the nephron. The capsule lumen (CL) is continuous with a sequence of tubules.Filtrate flows from CL to PCT to LH to DCT to CT.

PCT

LH

DCT

CL

CT

PCT

PCT

CT

LH

DCT

Filtration occurs at the Glomerulus90 two-liter bottles of water /day =180 L

Reabsorb99% of the Filtrate

99% of the Filtrate is returned to the venous system

Tubules

Filtrate

1% Filtrate passes out of the Collecting Duct as Urine.

PCT

DCTAfferent Arteriole Efferent Arteriole

Glomerular Capsule

Glomerular Capillaries

1. Filtration: Production of Filtrate

2. Reabsorption: Reabsorb 99% of the Filtrate

3. Secretion: of ions and chemicals

Ammonia is ToxicUrea is not Toxic

Urea is formed when amino acids are broken down

Urinary Bladder

Involuntary controlVoluntary control

Urinary Bladder fills and then empties when you feel the “Urge to Purge”.

At 200ml

You are expected to void about 2 liters (<1%) per day.

ECF = IF + P=12 + 3= 15LT= ICF+ ECF = 25+15= 40L

Urine output is monitored for a patient via a catheter and bag.

In the cells

Between the cells

In the blood

At the level of the tissue, multiple systems deliver and remove substances.

Maintaining Homeostasis

Control of Blood Homeostasis

Water decreases

Brain ReceptorsDetect change

Control Center

Effectors

The Role of the Kidney is maintaining the homeostasis of Blood Pressure & Volume

Blood Pressure & Volume Drops1. Kidney releases RENIN (a hormone).2. Blood Pressure Increases and Blood Volume increases.

Blood Pressure & Volume Drops1. The Brain creates ADH (a hormone) and secretes it via the Posterior Pituitary .2. ADH affects the Kidney.3. Kidney reabsorbs more water.4. Blood Volume increases.

AntiDiuretic Hormone= ADH

H+ in urine reduces the pH so that urine is more acidic.A more acidic urine reduces the frequency of Urinary Tract Infections (UTI)

Maintaining Blood pH Homeostasis

Bicarbonate ion is excreted which increases the number of H+ so that blood is more acidic.

Bicarbonate ion is reabsorbed which decreases the number of H+ so that blood is more basic.

Less H+

7. 45-Blood-

pH7.35

More H+

More bicarbonate ions

less bicarbonate

ions

Microscopy of the Kidney

glomerulus

tubules

Understand the Flow• What is

the Flow of Blood in the Kidney?

• What is the Flow of Filtrate in the Kidney?

• What is the Flow of Urine?