Urinary SystemUrinary System

Major Parts of the Machinefood, water intake oxygen intake

elimination of carbon dioxide

Digestive System Respiratory System

Circulatory SystemUrinary System

elimination of excess watersalts, wastes

rapid transportto and from allliving cells

eliminationof foodresidues

nutrients,water,salts

carbondioxide

watersolutes

oxygen

Based on: Starr, C., Biology: Concepts and Applications, Brooks/Cole

Overview of Lesson• Formation of urine • Urinary system• Water balance and alcohol• Problems of the urinary

tract

When protein is broken down When protein is broken down in the body, it results in in the body, it results in nitrogenous waste that must be nitrogenous waste that must be eliminated from the bodyeliminated from the body

Based on: Mader, S., Inquiry Into Life, McGraw-Hill

Protein

All 20 amino acids have a nitrogen group (NHAll 20 amino acids have a nitrogen group (NH22). ). When broken down for energy, the nitrogen group When broken down for energy, the nitrogen group is converted to ammonia (NHis converted to ammonia (NH33).).

Examples of Amino Acids

Based on: Mader, S., Inquiry Into Life, McGraw-Hill

Ammonia is Ammonia is converted into urea converted into urea by the liver. Urea is by the liver. Urea is then transported in then transported in the blood to the the blood to the kidneys where the kidneys where the urea is removed urea is removed from the blood.from the blood.

Circulatory System

Based on: Mader, S., Inquiry Into Life

Urea is less toxic than ammonia Urea is less toxic than ammonia and can be transported in the and can be transported in the blood to the kidneyblood to the kidney

HH22N - C - NHN - C - NH22

ureaurea

OO

Formation of UrineFormation of UrineAmino acids in protein are broken down, Amino acids in protein are broken down,

resulting in production of ammoniaresulting in production of ammonia

Ammonia is converted to urea in liverAmmonia is converted to urea in liver

Urea travels in blood to kidneys, where Urea travels in blood to kidneys, where removed from blood and incorporated removed from blood and incorporated

into urineinto urine

Overview of Lesson• Amino acids, ammonia and

urea • Urinary system• Water balance and alcohol• Problems of the urinary

tract

Urinary System

Based on: Mader, S., Inquiry Into Life, McGraw-Hill

Anatomy of the Kidney

Based on: Mader, S., Inquiry Into Life, McGraw-Hill

Urine Formation by NephronUrine Formation by NephronBlood pressure forces water, glucose, Blood pressure forces water, glucose,

amino acids and urea from capillaries into amino acids and urea from capillaries into nephronnephron

Glucose and amino acids are reabsorbed Glucose and amino acids are reabsorbed into blood from nephroninto blood from nephron

Some water is reabsorbed into bloodSome water is reabsorbed into blood

Urine is urea and salt concentrated in waterUrine is urea and salt concentrated in water

Nephron

Based on: Mader, S., Inquiry Into Life, McGraw-Hill

Urine moves from the Urine moves from the collecting ducts through the collecting ducts through the kidney pelvis to the ureterkidney pelvis to the ureter

Based on: Mader, S., Inquiry Into Life, McGraw-Hill

Urine moves from the kidneys, Urine moves from the kidneys, through the ureters to the bladder through the ureters to the bladder and finally through the urethraand finally through the urethra

Based on: Mader, S., Inquiry Into Life, McGraw-Hill

Overview of Lesson• Amino acids, ammonia and

urea • Urinary system• Water balance and alcohol• Problems of the urinary

tract

Regulation of Water BalanceRegulation of Water BalanceBrain monitors water content of bloodBrain monitors water content of blood

If low water content, pituitary releases ADHIf low water content, pituitary releases ADH

ADH travels in blood to nephronADH travels in blood to nephron

ADH causes more water to move from urine ADH causes more water to move from urine back into bloodback into blood

Nephron

Based on: Mader, S., Inquiry Into Life, McGraw-Hill

Alcohol consumption Alcohol consumption suppresses the production of suppresses the production of ADH by the pituitary. ADH by the pituitary. Why would this result in Why would this result in dehydration and a hangover?dehydration and a hangover?

Overview of Lesson• Amino acids, ammonia and

urea • Urinary system• Water balance and alcohol• Problems of the urinary

tract

Kidney stones form in the kidney Kidney stones form in the kidney pelvis. There are 4 types of stones.pelvis. There are 4 types of stones.

•Calcium stones (most common)•Uric acid stones•Bacteria caused stones•Cystein stones

Based on Mayo Clinic Health Letter

Kidney stones cause pain when Kidney stones cause pain when they pass down the ureters to the they pass down the ureters to the bladder and urethrabladder and urethra

Based on: Mader, S., Inquiry Into Life, McGraw-Hill

Urinary Tract Infection (UTI)Urinary Tract Infection (UTI)• Second most common infection following respiratory Second most common infection following respiratory

infections infections

• UTI occur when bacteria (UTI occur when bacteria (E. coliE. coli) from the digestive tract get ) from the digestive tract get into the opening of the urinary tract and multiplyinto the opening of the urinary tract and multiply

• Bacteria first infect the urethra, then move to the bladder Bacteria first infect the urethra, then move to the bladder and finally to the kidneys and finally to the kidneys

• UTI tend to occur more in women than menUTI tend to occur more in women than men

Symptoms of UTIsSymptoms of UTIs• Urge to urinate but only small Urge to urinate but only small

amount of urine producedamount of urine produced• Pain and burning sensation in Pain and burning sensation in

bladderbladder• Fever Fever • Blood in urineBlood in urine