Urinary System

Question 1

Functions of kidneys:

Answer 1

Filtering impurities from blood and preventing poisons fatally accumulating in the body

Question 2

Location of kidneys

Answer 2

Behind the stomach, one on each side of the spine

Question 3

How many layers do kidneys have?

Answer 3

3

Question 4

3 layers of the kidney: (outside to inside)

Answer 4

Cortex, medulla and pelvis

Question 5

What do the cortex and medulla contain?

Answer 5

Nephrons

Question 6

Nephron

Answer 6

Tiny blood filtration unit

Question 7

What is the waste product of filtration?

Answer 7

Urine

Question 8

Where does the waste product of filtration collect?

Answer 8

In the kidney’s pelvis

Question 9

How the kidneys work: Part 1 - blood

Answer 9

Blood for processing enters the medulla from the renal artery
Inside the medulla and cortex, the artery splits into tiny coiled blood vessels

Question 10

Glomerulus

Answer 10

A coiled blood vessel from an artery

Question 11

What nearly surrounds the glomerulus?

Answer 11

Bowman’s capsule

Question 12

Bowman’s capsule

Answer 12

A pinhead - sized sac that almost completely surrounds the glomerulus

Question 13

How do the kidneys work: Part 2 - pressure

Answer 13

Pressure forces water and dissolved chemicals from the blood in the glomerulus into the Bowman’s capsule. The filtered liquid then continues through a tubule surrounded by capillaries

Question 14

How do the kidneys work: Part 3 - reabsorption

Answer 14

Capillaries that surround a tubule reabsorb into the blood most of the water and such useful chemicals as amino acids.

Question 15

How do the kidneys work: Part 4 - treated blood

Answer 15

The treated blood (nutrients reabsorbed into) then leaves the kidneys via the renal vein

Question 16

How do the kidneys work: Part 5 - wastes

Answer 16

Meanwhile, wastes remaining in the convoluted tubule flow on via a collecting tubule to the kidney’s pelvis. These wastes now form urine.
From the kidney’s pelvis, urine leaves the kidney through a tube known as the ureter

Question 17

Urine definition

Answer 17

An amber liquid mostly made of water, uric acid, urea and inorganic salts

Question 18

What happens to the urine output in sleep/when sweating (perspiration)?

Answer 18

It drops/reduces (less pee)

Question 19

What happens to the urine output after someone has been drinking more liquid than usual?

Answer 19

It rises (more pee)

Question 20

Bladder

Answer 20

A bag for storing urine before it leaves the body (hollow, muscular)

Question 21

Hip bone

Answer 21

Pubis

Question 22

Location of the bladder

Answer 22

Lying just behind the hip bone (pubis)

Question 23

What connects the bladder to the kidneys?

Answer 23

Two (macaroni - sized) tubes called ureters

Question 24

What opens from the bottom of the bladder?

Answer 24

A broad tube called the urethra (where your pee comes out)

Question 25

What keeps the urethra closed normally?

Answer 25

A ring of muscles called the **urethral sphincter**

Question 26

What is a bladder like when its empty?

Answer 26

Flat

Question 27

How does the bladder work: Part 1 - ureters

Answer 27

Urine drips into the bladder through the ureters. The bladder's walls relax as it fills

Question 28

How does the bladder work: Part 2 - brain signal

Answer 28

When the bladder holds about a cupful of urine, nerves start sending the brain 'urinate' signals

Question 29

How does the bladder work: Part 3 - urination

Answer 29

Urination occurs when the **urethral sphincter relaxes** and the **bladder wall contracts**, forcing urine out through the urethra