18 - Urinary System and Fluid Balance Flashcards
The urinary system consists of ..
- Two kidneys
- Two ureters
- The urinary bladder
- The urethra
What are the major functions of the urinary system?
- Excretion
- Regulation of blood volume and pressure.
- Regulation of the concentration of solutes in the blood.
- Regulation of extracellular fluid pH
- Regulation of red blood cell synthesis
- Regulation of vitamin D synthesis.
Explain this urinary system function: Excretion.
The kidneys are the major excretory organs of the body. They remove waste products fromt he blood. Many waste products are toxic, but most are metabolic by-products of cells, and substances absorbed from the intestine. The skin, liver, lungs, and intestines eliminate some of these waste products, but they cannot compensate if the kidneys fail to function.
Explain this urinary system function: Regulation of blood volume and pressure.
The kidneys play a major role in controlling the extracellular fluid volume in the body. They can produce either a large volume of dilute urine or a small volume of concentrated urine. Thereby, the kidneys regulate blood volume and blood pressure.
Explain this urinary system function: Regulation of the concentration of solutes in the blood
The kidneys help regulate the concentration of the major molecules and ions, such as glucose, Na+, Cl-, K+, Ca2+, HCO3-, and HPO4(2-)
Explain this urinary system function: Regulation of extracellular fluid pH.
The kidneys excrete variable amounts of H+ to help regulate extracellular fluid pH.
Explain this urinary system function: Regulation of red blood synthesis.
The kidneys secrete a hormone, erythropoietin, which regulates the synthesis of red blood cells in bone marrow.
Explain this urinary system function: Regulation of vitamin D synthesis.
The kidneys play an important role in controlling blood levels of Ca2+ by regulating the synthesis of vitamin D.
Each kidney is surrounded by ..
A renal capsule.
What is the hilum?
On the medial side of each kidney is the hilum, where the renal artery and nerves enter and where the renal vein, ureter, and lymphatic vessels exit the kidney. The hilum opens into a cavity called the renal sinus, which contains blood vessels, part of the system for collecting urine, and adipose tissue.
The kidney is divided into…
An out cortex and an inner medulla.
What is the name of the functional unit of the kidney?
The nephron.
The functional unit of the kidney is the nephron. Each nephron consists of …
- A renal corpuscle
- A proximal convoluted tubule
- A loop of Hele
- A distal convoluted tubule.
Fluid is forced into the …..
Fluid is forced into the renal corpuscle,
Fluid is forced into the renal corpuscle and then flows into
Fluid is forced into the renal corpuscle and then flows into the proximal convoluted tubule.
Fluid is forced into the renal corpuscle and then flows into the proximal convoluted tubule. From there, it flows into
Fluid is forced into the renal corpuscle and then flows into the proximal convoluted tubule. From there, it flows into the loop of Henle.
Fluid is forced into the renal corpuscle and then flows into the proximal convoluted tubule. From there, it flows into the loop of Henle. Each loop of Henle consists of …
Each loop of Henle consists of a descending limb and an ascending limb.
Each loop of Henle consists of a descending limb and an ascending limb. The limbs are further categorised into segments:
Each loop of Henle consists of a descending limb and an ascending limb. The limbs are further categorised into segments: the thin segment of the descending limb, the thin segment of the ascending limb, and the thick segment of the ascending limb.
The descending limb extends toward …
The descending limb extends toward the renal sinus.
The descending limb extends toward the renal sinus, where it makes a hairpin turn, and the ascending limb extends back toward …
the cortex.
The fluid flows through the ascending limb of the loop of Henle to the …
The fluid flows through the ascending limb of the loop of Henle to the distal convoluted tubule.
The fluid flows through the ascending limb of the loop of Henle to the distal convoluted tubule. Several distal convoluted tubules empty into …
The fluid flows through the ascending limb of the loop of Henle to the distal convoluted tubule. Several distal convoluted tubules empty into a collecting duct, which carries the fluid from the cortex, through the medulla.
The fluid flows through the ascending limb of the loop of Henle to the distal convoluted tubule. Several distal convoluted tubules empty into a collecting duct, which carries the fluid from the cortex, through the medulla. Many collecting ducts empty into a single ..
Many collecting ducts empty into a single papillary duct, and the papillary ducts empty their contents into a calyx.
The renal corpuscle of the nephron consists of …
- the Bowman capsule
2. The glomerulus
What is the Bowman capsule?
The Bowman capsule consists of the enlarged end of the nephron, which is indented to form a double-walled chamber.
What is the glomerulus?
The glomerulus is a tuft of capillaries that resembles a ball of yarn and lies within the indentation of the Bowman capsule.
The Bowman capsule opens into the x, which carries fluid away form the capsule.
Proximal convoluted tubule.
The inner layers of the Bowman capsule consist of specialised cells called …
podocytes.
What is the filtration membrane?
The endothelium of the glomerular capillaries, the podocytes and the basement membrane together form a filtration membrane,
What is the first step of urine formation?
In the first step of urine formation, fluid consisting of water and solutes smaller than proteins, passes from the blood in the glomerular capillaries through the filtration membrane into the Bowman capsule.
In the first step of urine formation, fluid consisting of water and solutes smaller than proteins, passes from the blood in the glomerular capillaries through the filtration membrane into the Bowman capsule. What is the name of this fluid?
Filtrate.
The thin segment of the descending limb of the loop of Henle is permeable to …
water and, to a lesser degree, solutes.