kidney physiology
DESCRIPTION
TRANSCRIPT
Kidney Physiology (pg 4)
Macroscopic Structure of the Kidney
• Cortex: Outer region
Macroscopic Structure of the Kidney
• Cortex: Outer region • Medulla: Inner region
Macroscopic Structure of the Kidney
• Cortex: Outer region • Medulla: Inner region• Renal pelvis: large cavity that collects the
urine as it is produced. Continuous with ureter
Nephrons• Nephrons are the functional unit of the kidney
Nephrons• Nephrons are the functional unit of the kidney• Over 1 million nephrons per kidney
Nephron Structure
Nephrons have two parts:
Nephron Structure
Nephrons have two parts:1. Renal corpuscle
a. Glomerulus: cluster of capillaries
Nephron Structure
Nephrons have two parts:1. Renal corpuscle
a. Glomerulus: cluster of capillariesb. Glomerular (Bowman’s) Capsule: cup that
surrounds the glomerulus and receives blood filtrate from it
2. Renal tubulea. Proximal convoluted tubule: Highly coiled. Located in cortex
2. Renal tubulea. Proximal convoluted tubule: Highly coiled. Located in cortexb. Loop of Henle: A hairpin loop that dips into the medulla, makes a U-turn, and ascends back to the cortex
2. Renal tubulea. Proximal convoluted tubule: Highly coiled. Located in cortexb. Loop of Henle: A hairpin loop that dips into the medulla, makes a U-turn, and ascends back to the cortexc. Distal convoluted tubule: Coiled, in cortex
Urine Formation• Nephrons form urine in 3 steps
1. Filtration: Water and small solutes enter the nephron (blood cells and proteins do not enter). Filtrate is similar to blood plasma.
Urine Formation• Nephrons form urine in 3 steps
1. Filtration: Water and small solutes enter the nephron (blood cells and proteins do not enter). Filtrate is similar to blood plasma. 2. Reabsorption: Useful substances (water, glucose, amino acids, needed ions) are transported out of the filtrate and back into the blood
Urine Formation• Nephrons form urine in 3 steps
1. Filtration: Water and small solutes enter the nephron (blood cells and proteins do not enter). Filtrate is similar to blood plasma. 2. Reabsorption: Useful substances (water, glucose, amino acids, needed ions) are transported out of the filtrate and back into the blood3. Secretion: Harmful substances (H+, excess K+, some drugs and poisons) are removed from the blood and put into the filtrate
Output (pg 5)
• Color code nephron diagram
Hormonal Control• Hormones regulate the reabsorption of water
and electrolytes by the kidneys
Hormonal Control• Hormones regulate the reabsorption of water
and electrolytes by the kidneys• If blood volume drops, the pituitary gland
releases antidiuretic hormone (ADH)
Hormonal Control• Hormones regulate the reabsorption of water
and electrolytes by the kidneys• If blood volume drops, the pituitary gland
releases antidiuretic hormone (ADH)• ADH causes the kidney duct cells to reabsorb
more water and produce less urine
Hormonal Control• Hormones regulate the reabsorption of water
and electrolytes by the kidneys• If blood volume drops, the pituitary gland
releases antidiuretic hormone (ADH)• ADH causes the kidney duct cells to reabsorb
more water and produce less urine• Alcohol inhibits ADH production
Hormonal Control• Hormones regulate the reabsorption of water
and electrolytes by the kidneys• If blood volume drops, the pituitary gland
releases antidiuretic hormone (ADH)• ADH causes the kidney duct cells to reabsorb
more water and produce less urine• Alcohol inhibits ADH production• Inability to produce ADH is called diabetes
insipidus (water diabetes). Affected individuals produce up to 25 liters of very dilute urine per day and are constantly thirsty