L19 Ch26 The Urinary System

Practice flashcards covering the anatomy, physiology, and clinical aspects of the urinary system based on Chapter 26 lecture notes.

What is the primary function of the kidneys as described in the lecture?

To produce urine, a liquid waste product containing various metabolic byproducts.

Where are the kidneys located in the body?

In the posterior abdominal cavity.

What is the function of the uretors?

These are muscular tubes responsible for transporting urine from each kidney down to the urinary bladder.

How is the urinary bladder described anatomicaly?

A distensible muscular sack located in the pelvic cavity that serves as a temporal storage reservoir for urine.

What is the function of the urethra?

A single tube that extends from the bladder to the external environment for the elimination of urine.

Which endocrine glands sit superior to each kidney and help regulate fluid balance and blood pressure?

The adrenal glands.

Contrast the roles of the renal artery and the renal vein.

The renal artery delivers oxygenated blood with waste products to the kidney for filtration, while the renal vein carries filtered blood away to the inferior vennea.

What are the four main categories of urinary system functions?

Excretion of metabolic waste, regulation of water salt balance, regulation of asset base balance, and secretion of hormones.

How does the liver handle toxic ammonia during protein metabolism?

The liver converts ammonia into a less toxic substance called ura through the ura cycle.

What are the clinical terms for the accumulation of ura in the blood due to kidney failure?

Uria or esotia.

Why are blood levels of creatine used as a clinical indicator of kidney function?

Because the rate of creatine production is relatively constant and proportional to muscle mass, so elevated levels suggest impaired filtration.

What condition is caused by the precipitation of uric acid crystals in the joints?

Gout.

What is the target blood pH that the kidneys help maintain through pH homeostasis?

Around $7.4$.

What role does the hormone eriththropoine (EPO) play in the body?

It stimulates red blood cell production in the bone marrow in response to low oxygen levels (hypoxia).

What is the active form of Vitamin D converted by the kidneys?

Calcitrial.

What enzyme is secreted by the kidneys to initiate a hormonal cascade for regulating blood pressure?

Renine (or renin).

What does the term 'retroparonium' (or retroperitoneal) indicate about the kidneys' location?

They are located behind the paronium (serous membrane) against the posterior abdominal wall.

Why is the left kidney typically situated slightly superior to the right kidney?

Due to the presence of the liver in the upper right quadrant, which displaces the right kidney slightly inferiorly.

What is the name of the prominent indentation on the medial side of the kidney where vessels enter and exit?

The helium.

What is the function of the renal capsule?

A tough fibrous outer layer that provides a protective barrier against trauma and infection and helps maintain the kidney's shape.

Differentiate between the renal cortex and the renal medula.

The renal cortex is the superficial region where initial filtration occurs, while the renal medula is the deeper region crucial for concentrating urine.

What are the renal pyramids and where are they located?

Triangular or cone-shaped structures located within the medula.

What is a 'renal lobe' composed of?

A single renal pyramid, the portion of the renal cortex superficial to it, and the adjacent renal columns on either side.

Trace the arterial blood flow in the kidney from the renal artery to the glomeus.

Renal artery $\rightarrow$ segmental artery $\rightarrow$ interlo arteries $\rightarrow$ arquate arteries $\rightarrow$ cortical radiate arteries $\rightarrow$ aphrine arterials $\rightarrow$ glomeus.

What is the difference between the arterial and venos pathways in the kidney?

The venos pathway lacks segmental veins.

What are the two main components of a nephron?

The renal corpus skull and the renal tubule.

What structures make up the renal corpus skull (renal corpuscle)?

The glomeular (Bowman's) capsule and the glomeilus (capillary network).

In order, what are the segments of the renal tubule?

Proximal convoluted tubule (PCT), nephron loop (loop of henley), and distal convoluted tubio (DCT).

Which specialized cells in the renal corpuscle have foodike processes that create filtration slits?

Podocytes.

Why does the proximal convoluted tubule (PCT) have a brush border of microbilly and numerous mitochondrias?

To increase surface area for reabsorption and provide energy for active transport.

Compare the permeability of the thin descending limb and the thick ascending limb of the loop of henley.

The thin descending limb is highly permeable to water, while the thick ascending limb is impermeable to water but actively transports salts.

Which hormones regulate reabsorption in the distal convoluted tubule (DCT)?

Aldoone (aldosterone) and parathyroid hormone.

How does antiduretic hormone (ADH) affect the collecting ducts?

It regulates their permeability to water for the final concentration of urine.

Identify the three main steps involved in urine formation.

Glular filtration, tubular reabsorption, and tubular secretion.

What is the 'trigon' of the urinary bladder?

A triangular region on the posterior inferior wall where the uretors enter; it is a common site for persistent urinary tract infections.

What is the detrusor muscle?

A smooth muscle layer in the bladder wall consisting of three interwoven layers that contract to expel urine.

Distinguish between the internal and external urethral sphincters.

The internal sphincter is smooth muscle (involuntary), while the external sphincter is skeletal muscle (voluntary).

What is the approximate length of the urethra in biological females versus biological males?

Approximately $4\,cm$ in females and $20\,cm$ in males.

What triggers the urinary avoiding reflex (micturition)?

Activation of stretch receptors in the bladder wall by a significant increase in bladder volume.

How does aging affect the number of functional nephrons?

There is a decline of approximately $30$ to $40\%$ in the number of nephrons between the ages of $25$ and $85$.