11. Urinary System Flashcards
(97 cards)
The tubes that connect the kidneys to the bladder
Ureters
The tube exiting the bladder to remove urine from the body
Urethra
List 4 functions of the urinary system
- Excretion of unwanted substances
- Maintenance of water & electrolyte balance
- pH regulation of body fluids
- Production of hormones
- Regulation of red blood cell production
- Regulation of blood glucose levels
- Regulation of blood pressure, volume and osmolarity
What gas is found in all metabolic waste products?
Nitrogen
List the 3 metabolic waste products.
- Urea (from protein metabolism)
- Uric Acid (from purine metabolism)
- Creatine (from muscle metabolism)
What is the main ion excreted in urine?
Hydrogen (H+)
What is the minimum urine content required to clear body waste?
500 ml/day
What are electrolytes?
Charged atoms in solution
Name the 3 most important electrolytes that are regulated by the kidney.
Sodium (Na+)
Potassium (K+)
Hydrogen (H+)
An excess in what electrolyte is a reflection of an acidic solution?
Hydrogen (H+)
What pH should blood be?
7.35 - 7.45
What are the two primary pH control systems in the body and how do they work?
- Lungs - excrete CO2 through respiration
- Kidneys - excrete H+ into urine and produce the buffer HCO3 (bicarbonate)
What are the two main hormones produced by the kidneys and what are their functions?
Calcitriol - the active form of vitamin D that increases bone formation by increasing calcium.
Erythropoietin - stimulates erythropoiesis
How does calcitriol increase bone formation?
1) Stimulates calcium and magnesium update in the GIT
2) Reduces calcium loss in the kidneys
Bone formation increases due to the increase in calcium.
What hormone is released by the kidneys in response to hypoxia?
Erythropoietin
In renal failure, erythropoietin production is inadequate and hence results in what pathology?
Anaemia
What is the renal threshold for glucose?
9 mmol/L
What is a normal blood glucose level?
4 - 7 mmol/L
How do the kidneys make glucose?
The kidneys are able to make glucose from the amino acid glutamine to help elevate blood sugar levels when hypoglycemia.
NB this is called gluconeogenesis
How do the kidneys control blood volume, pressure and concentration?
1) Conserving or eliminating water in urine.
2) Regulating the solute loss in the urine helps maintain a constant blood concentration.
3) Secrete the enzyme renin which activates the renin-angiotensin-aldosterone pathway increasing blood pressure.
Where are the kidneys located?
- Partially protected by the 11th & 12th ribs.
- Between vertebra levels T11 - L3
- Right kidney is lower because the liver occupies space on the right.
What are the 3 layers surrounding the kidney?
1) Renal capsule - deep later of connective tissue
2) Adipose capsule - middle layer of fatty tissue
3) Renal fascia - superficial layer of connective tissue
What are the two regions within the kidneys?
1) Renal cortex - superficial, light red area
2) Renal medulla - dark area consisting of several cone-shaped structures
Describe the functional portions of the kidneys.
Several cone-shaped structures called renal pyramids.
The apex of each renal pyramid is called the renal papilla.