Excretion Flashcards
What is the urinary system responsible for?
It is responsible for removing waste and excess fluids & nutrients from the body
What is the main function of the kidneys?
Sit of urine production
What are the three sections of the kidneys?
- Renal Pelvis
- Renal Cortex
- Renal Medulla
What are the ureters?
28 cm long tube attached to each kidney that transport urine to bladder
How do the ureters transport urine
Movement occurs via peristalsis
What is the role of the bladder
Temporarily stores urine
What is the urethra?
Single tube by which urine exits body
Males: ~20 cm long (merges with vas deferens)
Females: ~4 cm long
What are the nephron?
The functional units of the kidney
How many nephrons does each kidney contain?
Approx. 1 million
What is the renal cortex?
The renal cortex is the outer layer of the kidney
which are then passed on to the renal pelvis and collected in the bladder. The renal cortex is surrounded by the renal medulla, which is the inner layer of the kidney. Together, the renal cortex and renal medulla form the functional units of the kidney, known as nephrons.
What is the renal medulla?
The renal medulla is the inner layer of the kidney and is responsible for concentrating urine as it is produced by the kidneys. The renal medulla is surrounded by the renal cortex, and together, these two structures form the functional units of the kidney, known as nephrons. The renal medulla plays a key role in the urinary system, as it helps to filter waste products and excess fluids from the blood and excrete them from the body.
What is the renal pelvis?
A funnel-shaped structure located in the center of the kidney where urine is collected from the renal medulla and flows into the ureter to be excreted
What are the glomerulus?
The renal artery splits into glomerulus which is a high pressure capillary bed with small pores embedded in its walls
What is Bowman’s Capsule?
A cup-like structure that surrounds the glomerulus
Fill in the blank:
Together, the renal medulla and renal cortex form the _____________.
NEPHRONS
What is glomerular filtration?
The movement of water and small solutes from the glomerulus into Bowman’s capsule through small pores in the tissue walls of the glomerulus that allow small particles to pass through, but large proteins are kept out.
(Blood —-> Nephron)
How does filtration occur in the glomerulus?
The glomerulus have small pores which allow small particles to pass through into Bowman’s Capsule, but keep large proteins out
How much blood passes through the kidneys each day? Why?
Up to 2000L of blood pass through kidneys each day because the blood pressure is four times higher than other capillary beds within body
What is the role of efferent arterioles?
The efferent arterioles are small arteries that carry blood away from the glomeruli and branch into the peritubular capillaries
What are peritubular capillaries?
A network of small capillaries that surround the tubule of the nephron that are are responsible for carrying blood filtered away from the renal tubules and back into the circulatory system through the renal vein
What are the three sections of the reabsorption tubule?
- Proximal tubule
- Loop of Henle (ascending & descending)
- Distal tubule
Fill in the blank:
From Bowman’s Capsule, filtrate travels into the ___________ __________.
PROXIMAL TUBULE
What is tubule reabsorption?
Useful solutes are reabsorbed from the proximal tubule back into bloodstream through the peritubular capillaries via active and passive transport (respectively, water returns to the blood through osmosis)
How does active transport occur in the proximal tubule?
The cells of the proximal tubule have many mitochondria which provide energy for the active transport of glucose and sodium
