What are the main functions of the Urinary System
Eliminates waste products
-Nitrogenous
-Drugs
- Toxins
Regulates aspects of homeostasis
-Water balance -Activation of Vitamin D
-Acid-base balance in blood -Blood pressure
-RBC production -Electrolytes
What are the size,shape, and location of the kidneys
Size: 12cm
Shape: Bean shape organ
Location: At level of T12 and L3 vertabrae, retroperitoneally
Starting at the aorta, trace the blood flow through the kidney and back to the Inferior Vena Cava
Aorta-renal A.- Segmental A-Interlobar A,- Arcuate A.-Cortical Radiate A-Afferent Arteriole-Glomerular Capillaries-Efferent Arteriole- Peritubular Capillaries-Cortical Radiate V-Arcuate V- Interlobar V- Renal V- IVC
What are the two main parts of the nephron
Glomerulus
Renal tubule
What are the 4 sections of the renal tubule
Glomerulus (Bowmans) Capsule
Proximal Convoluted Tubule
Loop of Henle
Distal Convoluted Tubule
What are the 2 capillary beds associated with the nephron and where are they located in relationship to the Glomerulus
Glomerulus Capillaries: Arise from the Afferent Arteriole
Peritubular Capillaries: Arise from the Efferent Arteriole
Where are the Juxtaglomerular Apparatus found and what are the 2 parts
Found near the end of ascending nephron loop passes between and contacts the afferent and efferent arterioles,
Macula Densa
Juxtaglomerular cells
Describe what the 3 steps to urine formation are.
- Glomerular Filtration:
- glomerular capillaries filtrate plasma
- water and solutes smaller than proteins are forces through capillary wall
- Tubular Reabsorption:
- water glucose amino acids and needed ions are transported out of the filtrate into the tubule cells and then enter the capillary blood
- Tubular Secretion:
- H-,K+creatine and drugs are removed from the peritubular blood and secreted by the tubule cells into the filtrate
What are the nitrogenous waste products found in the urine
- urea: protein breakdown
- uric acid: nucleic acid breakdown
- creatine: associated with creatine metabolism in muscles
What are the nitrogenous waste products found in the urine
- urea: protein breakdown
- uric acid: nucleic acid breakdown
- creatine: associated with creatine metabolism in muscles
What are some of the substances NOT found in the urine
- Glucose -Blood protiens
- RBC -WBC
- Hemoglobin -Bile
What are the 4 layers of the bladder wall
Innermucosa coat submucosa coat Muscular coat -layers of smooth muscle -called the Detrusor muscle Serosa coat
What type of cells make up the bladder mucosa and is special about these cells
- Transitional Cells
the thickness of this tissue changes as the bladder expands and contracts
Describe the structural and function of Urethral Sphincters
Internal Urethral Sphincter- involuntary and made of smooth muscle
External Urethral Sphincter- voluntary and made of skeletal muscle
Function:
Females is releases urine
Males releases urine and is a passageway for sperm cells
