Excretory system

Question 1

Path of Urine

Answer 1

1. ***Kidney (urine formation)
2. Ureter
3. Bladder (urine storage)
4. Urethra
5. Exit the body - Toilet

Question 2

nephron

Answer 2

• filtration unit of the kidney*
• produce filtrate

Question 3

Filtration

Answer 3

the mass movement of water and solutes from plasma to the renal tubule that occurs in the renal corpuscle.

Question 4

When does filtration begin?

Answer 4

when blood from the renal artery enters the glomerulus.

Question 5

glomerulus

Answer 5

a small, dense network of capillaries where filtration occurs inside the Bowman’s capsule.

Question 6

path of small substances

Answer 6

some will be reabsorbed in renal tubule. Any excess will be eliminated through the collecting duct as urine.

Question 7

path of large substances

Answer 7

such as proteins and blood cells, are too big to pass through the capillary walls and would leave the kidney through the renal vein and return to the blood.

Question 8

journey through a kidney

A red blood cell

Answer 8

Renal artery → glomerulus → capillaries → renal vein

Question 9

journey through a kidney

A large protein

Answer 9

renal artery → glomerulus → capillaries → renal vein

Question 10

journey through a kidney

A molecule of water that is essential to the body

Answer 10

renal artery → glomerulus → capillaries → renal vein

Question 11

Journey through a Kidney

A molecule of urea (a toxic waste)

Answer 11

renal artery → glomerulus → renal tubule → ureter → bladder

Question 12

Journey through a kidney

A molecule of glucose (sugar)

Answer 12

SOME:
renal artery → glomerulus → renal tubule → renal vein
OTHERS:
renal artery →capillaries → renal vein

Question 13

journey through a kidney

A molecule of water that needs to be removed from the body to keep the water balance right.

Answer 13

renal artery → glomerulus → renal tubule → ureter → bladder

Question 14

Osmosis in the excretory system

Answer 14

• gets waste products out of your blood.
• get nutrients out of food
• accounts for fluid transport out of the kidney tubules and the gastrointestinal tract, into capillaries, and across cell membranes.
• facilitates the diffusion of solutes and water across the semi-permeable membrane thereby maintaining osmotic balance.
• A high salt concentration in the interstitial fluid outside of the nephron will provide a driving force for osmosis, allowing water to be recovered from the filtrate.

Question 15

Diffusion in the excretory system

Answer 15

- substances that your body can still use get reabsorbed.

• In order to get water to leave the filtrate through diffusion, the area surrounding the nephron must have a high salt concentration.

Question 16

organs of the excretory system

Answer 16

• skin
• lungs
• liver
• kidneys
• ureters
• urinary bladder
• urethra

Question 17

skin

Answer 17

• removes excess water, salts, and a small amouny of urea in sweat
• sweat is released in small amounts and helps maintain constant body temperature

Question 18

lungs

Answer 18

• blood transports carbon dioxide, a waste product made through cellular respiration frm the body cells to the lungs
• when you exhale, carbon dioxide and a small amount of water vapor are released
• regulating carbon dioxide levels is important for blood pH

Question 19

liver

Answer 19

• converts toxic nitrogen-based cellular waste from protein breakdown into urea, which is a less toxic compound
• urea is transported to the blood by the circulatory system to the kidneys for elimination

Question 20

kidneys

Answer 20

• a pair of fist size, bean shaped organs that filter out wastes, excess water, urea, salts, and metabolic waste from the blood
• inside the kidneys are “processing units” called nephrons, which are responsible for absorbing valuable substances and getting rid of waste in the blood.

Question 21

ureters

Answer 21

• a pair of tubes that transports urine from the kidneys to the urinary bladder

Question 22

urinary bladder

Answer 22

• stores urine until it is ready to be released through the urethra

Question 23

urethra

Answer 23

• empties the bladder and releases urine outside the kidney

Question 24

functions of the excretory system

Answer 24

• eliminate waste (urea, carbon dioxide) and toxins from the body
• regulate blood volume and blood pressure
• regulate blod pH
• balance body fluids by releasing excess water or holding onto water
• produce urine
• regulates the concentration of certain solutes in the blood

Question 25

glucose

Answer 25

a sugar that is not usually filtered out of the blood by the kidneys. Individuals with diabetes have too much glucose in their blood.