exam 4 urinary structures

kidney model

renal artery model

renal vein model

ureter model

urinary bladder model

urethra model

major calyx model

minor calyx model

renal (fibrous) capsule model

renal columns model

renal cortex model

renal hilum model

renal medulla structure

renal pelvis model

renal (medullary) pyramid model

major calyx dissection

minor calyx dissection

renal vein dissection

renal (fibrous) capsule dissection

renal columns dissection

renal cortex dissection

renal hilum dissection

renal medulla dissection

renal pelvis dissection

renal (medullary) pyramid

afferent arteriole model

collecting duct model

cortical nephron model

distal convoluted tubule model

efferent arteriole model

glomerular (bowman’s) capsule model

glomerulus model

juxtamedullary nephron model

loop of Henle model

peritubular capillaries model

proximal convoluted tubule model

vasa recta model

external urethral orifice male model

Internal urethral sphincter male model

Intermediate part of urethra (male) model

Prostatic urethra (male) model

Spongy urethra of (male) model

External urethra orifice male model

Trigone of the bladder model

Ureteric orifice model

External urethra orifice female model

Urethra (female) model

Urinary bladder female model

What are the main functions of the urinary system?

Excretes metabolic wastes (urea, uric acid, creatinine)

Regulates blood volume and blood pressure

Maintains electrolyte balance (Na⁺, K⁺, Ca²⁺)

Maintains acid-base balance (pH control)

Produces hormones (erythropoietin, renin)

Activates vitamin D (calcitriol)

What is micturition?

The process of urination—expelling urine from the bladder to the outside of the body.

Difference between internal and external urethral sphincters?

Smooth muscle (involuntary)

Located at bladder-urethra junction

-

Skeletal muscle (voluntary control)

Located in urogenital diaphragm

What is a nephron?

The functional unit of the kidney that filters blood and forms urine.

Two types of nephrons?

cortical nephron: Mostly in the cortex

Short loops of Henle

-

juxtamedullary nephron: Near medulla

Long loops of Henle → important for concentrating urine

Trace filtrate flow from glomerulus to outside of body.

Glomerulus → Glomerular capsule → Proximal convoluted tubule (PCT) → Nephron loop (Loop of Henle): Descending limb > Ascending limb → Distal convoluted tubule (DCT) → Collecting duct → Papillary duct → Minor calyx → Major calyx → Renal pelvis → Ureter → Urinary bladder → Urethra → Outside body

What are the three steps of urine formation?

Glomerular filtration – blood plasma filtered into capsule

Tubular reabsorption – useful substances returned to blood

Tubular secretion – additional wastes added to filtrate

male urethra

~20 cm long

Passes through prostate, penis

Functions in urine + semen transport

female urethra

~4 cm long

Short, straight

Only carries urine → higher UTI risk

Glomerular filtration

Movement of water and small solutes from blood into glomerular capsule.

Tubular reabsorption

Movement of substances from filtrate back into blood.

Tubular secretion

Movement of substances from blood into filtrate.

Micturition

Urination (emptying bladder).

Normal physical characteristics of urine?

Color: pale yellow → amber

Clarity: clear

Odor: slightly aromatic

Normal urine pH and specific gravity?

pH: ~4.6–8.0 (avg ~6)

Specific gravity: 1.001–1.035

What is normally found in urine?

Water (~95%)

Urea

Creatinine

Uric acid

Electrolytes (Na⁺, K⁺, Cl⁻)

What can urinalysis detect?

Glucose

Protein

Blood

Ketones

pH

Specific gravity

Infection indicators (WBCs, bacteria)

what is Glycosuria and what does it indicate

Glucose in urine → often indicates diabetes mellitus

what is Albuminuria and what does it indicate

Protein in urine → kidney damage (glomerular injury)

what is Ketonuria and what does it indicate

Ketones in urine → starvation or uncontrolled diabetes

what Hemoglobinuria and what does in indicate

Free hemoglobin in urine → hemolysis

what is Pyuria and what does it indicate

Pus (WBCs) in urine → infection

what is Casts and what does it indicate

Cylindrical structures (formed in tubules) → kidney disease

what is Calculi and what does it indicate

Kidney stones → formed from crystallized minerals

flow of urine in the body

Glomerulus → Capsule → PCT → Descending loop → Ascending loop → DCT → Collecting duct → Papillary duct → Minor calyx → Major calyx → Renal pelvis → Ureter → Bladder → Internal sphincter → Urethra → External sphincter → Outside