Introduction
Where is the left kidney located?
At the level of T12 to L3 vertebrae
What is the kidney protected by?
Muscle, fat, and the ribs.
What is the size of the kidney and where is the location?
The kidney is the size of a fist and lie on either side of the spine in the retroperitoneal space, between the parietal peritoneum and the posterior abdominal wall.
Where is the right kidney located?
Slightly lower to the left kidney due to displacement by the liver
What is the kidney covered with?
A fibrous renal capsule composed of dense, irregular connective tissue that helps to hold their shape and serve as protection.
What is the renal capsule covered by?
This capsule is covered by a shock-absorbing layer of adipose tissue known as the renal fat pad, and then by the tough renal fascia, which serves to firmly anchor the kidneys to the posterior abdominal wall in a retroperitoneal position.
What are nephrons?
the "functional units" of urine formation in the kidney
What percentage of cardiac output does the kidney get at rest?
The kidneys are well vascularized, receiving about 25 percent of the cardiac output at rest
What does the nephrons do?
To balance the plasma to homeostatic set points and excrete potential toxins in the urine. These structures take a simple filtrate of the blood and modify it into urine.
What is the system ability to filter blood?
about 2 to 3 million glomeruli, located in the cortex of each kidney.
What are the 3 functions of the urine formation?
Filtration, reabsorption, and secretion.
How does failure of the kidneys affect homeostasis?
You may experience weakness, lethargy, shortness of breath, anemia, widespread edema (swelling), metabolic acidosis, rising potassium levels, and heart arrhythmias
In order for the kidneys to perform its functions, what must the kidney do?
The kidneys acts as a blood filter, allowing excess ions and metabolic wastes to leave the body in the urine while reabsorbing needed substances such as water and nutrients back into the blood.
How much blood flows to the body that is delivered to the kidney each minute?
About 25 percent
What does the glomerulus do?
The glomerulus filters the blood based on particle size, large elements like blood cells, platelets, antibodies, and albumin do not enter the filtrate. All other solutes, such as ions, amino acids, vitamins, and wastes, are filtered to create a filtrate composition that is very similar to blood plasma.
What happens during tubular reabsorption?
Substances in the filtrate are returned to the blood in the peritubular capillaries. Substances such as water, glucose, and amino acids are almost completely reabsorbed, while ions are selectively reabsorbed based on the body’s needs.
Regulates homeostasis of electrolytes, fluid volume, and blood pH, as well as removing nitrogenous wastes from the body.
The Urinary System
What are the major function of the kidneys?
The filter metabolic wastes and ions from the blood, as well as maintain fluid, electrolyte, and acid-base homeostasis.
What happens during tubular secretion?
Substances such as waste products and excess ions move from the blood of the peritubular capillaries into the filtrate to be excreted in the urine.
What is a urinary bladder?
the primary organ that collects urine from both ureters
What is glomerulus?
As the afferent arteriole enters the nephron, it forms a tuft of high-pressure capillaries.
What does the urinary system consist of?
The paired kidneys and ureters, the urinary bladder, and the urethra.
What does the kidney produce and how does it affect what it produces?
How does the kidneys get a ureter?
As urine is formed, it drains into the minor and major calyces of the kidney, which merge to form the funnel-shaped renal pelvis within each hilum. As the renal pelvis extends out of the hilum, it narrows to become the ureter of each kidney.
Since urine does not drain into the bladder, it is propelled by what through the ureter?
Peristalsis