Urinary System

Question 1

Define Nephron?

Answer 1

The functional unit within a kidey.

Question 2

What is the Proximal convoluted tubule and what does it do?

Answer 2

The first part of the nephron tubule, it uses active transport to reabsorb sodium and chloride ions, sugars and water from the filtrate.

Question 3

What is the renal corpuscle?

Answer 3

The nephron structure that consists of a ball of blood capillaries and the surrounding tube that is the start of the nephron.

Question 4

What is the distal convoluted tubule?

Answer 4

The final part of the nephron tubules that does some final reabsorption and excretion, and carries urine to the collecting duct.

Question 5

What key role does the kidney have?

Answer 5

Responsible for filtering toxins out of the blood, regulating water, salt and pH in the blood, and for making urine.

Question 6

Define retroperitoneal?

Answer 6

Means “behind the abdominal cavity”, describing organs such as the kidneys that lie posterior to the abdomen serous membrane (which houses stomach, intestines etc)

Question 7

What is the Ureter?

Answer 7

The tube that carries urine from the kidney to the urinary bladder.

Question 8

What is urea recycling?

Answer 8

The act of drawing urea out of the collecting duct, to draw water out of the nephron loop, only to put that urea back in the filtrate a few steps back.

Question 9

What is the renal pelvis?

Answer 9

The funnel-shaped tube at the centre of the kidneys that delivers urine to the exit.

Question 10

What is the glomerulus?

Answer 10

The ball of blood capillaries in each nephron of a kidney where bulk filtration occurs.

Question 11

What is the glomerular capsule?

Answer 11

The proximal end of the nephron tube that surrounds the ball of blood capillaries.

Question 12

What is the nephron loop?

Answer 12

Also known as the Loop of Henles, the part of the nephron tubules that dips into the renal medulla, and return to the renal cortex, actively removing salts from the filtrate to build up a concentration gradient.

Question 13

Define the vasa recta?

Answer 13

The blood vessels in the kidney that carry blood after filtration, and follow the nephron to pick up reabsorbed materials.

Question 14

What is the renal medulla?

Answer 14

The inner layer of the kidneys, housing the deeper nephron loops and collecting tubules that deliver urine to the centre.

Question 15

What is the renal corpuscle?

Answer 15

The nephron structure that consists of a ball of blood capillaries and the surrounding tube that is the start of the nephron.

Question 16

Define the urinary bladder?

Answer 16

The organ lined with transitional epithelium, that stores urine produced in the kidneys until it can be excreted.

Question 17

What is the renal cortex?

Answer 17

The outermost layer of the kidneys housing the glomeruli and convoluted tubules of every nephron.

Question 18

What is the distal convoluted tubules and what does it do?

Answer 18

The final part of the nephron tubules that does some final reabsorption and excretion, and carries urine to the collecting duct.

Question 19

Define urea?

Answer 19

The compound made from nitrogenous metabolic wastes that the kidneys are responsible for filtering out

Question 20

What is the pontine storage centre?

Answer 20

The area of the pons in the brainstem that inhibits detrusor activity and decreases the urge to pee, by increasing sympathetic nervous system activity to the urinary bladder.

Question 21

What is the pontine micturition centre?

Answer 21

The area of the pons in the brainstem that activates detrusor activity and relaxes the internal sphincter to encourage and allow urination.

Question 22

Define the external urethral sphincter?

Answer 22

The ring of skeletal muscle, therefore under voluntary control, that controls the exit of the urinary bladder to the urethra.

Question 23

What are aquaporins?

Answer 23

The protein channels that allow water molecules to cross cell membranes, their positioning is important for regulating water reabsorption in the kidneys’ collecting ducts.

Question 24

Define the urethra?

Answer 24

The thin tube surrounded with smooth muscle that carries urine from the urinary bladder to the outside world.

Question 25

What is the official name for urination?

Answer 25

Micturition

Question 26

Define the internal urethral sphincter and what does it do?

Answer 26

The ring of smooth muscle and therefore under control of the autonomic nervous system that controls the exit of the urinary bladder to the urethra.

Question 27

What is the glomerular filtration rate?

Answer 27

The total amount of blood that passes through the kidney’s filtration organs every minute.

Question 28

What is the detrusor and what does it do?

Answer 28

The smooth muscle layer around the urinary bladder; when it contracts it creates pressure in the bladder to force urine out.

Question 29

How does auto-regulation of blood flow work in the kidneys?

Answer 29

When an increase in blood pressure stretches arterioles in the kidneys, this describes the fact that they vasoconstrict to reduce flow without feedback from the rest of the body.

Question 30

What is the ADH (Antidiuretic hormone)?

Answer 30

The hormone secreted by the posterior pituitary gland in reaction to low blood pressure, this triggers the kidneys to reabsorb more water from urine.