Science: Waste Disposal - ch.3.4

Question 1

Defecation

Answer 1

Getting rid of solid materials that cannot be used by body

Question 2

Excretion

Answer 2

The process of getting rid of waste materials that have been produced by the body

Question 3

Organs involved with excretion

Answer 3

Lungs, liver, skin and kidneys

Question 4

Lungs

Answer 4

Respiration produces carbon dioxide and water vapour as waste which are later exhaled

Question 5

Liver

Answer 5

Breaks down amino acids, old red blood cells and removes poisonous substances

Question 6

Urea

Answer 6

The liver breaks down excess amino acids into this substance

Question 7

Skin

Answer 7

Your body excretes excess heat through your skin by sweating

Question 8

Kidneys

Answer 8

Bean shaped organ that filters the blood to produce urine

Question 9

Kidney function 1

Answer 9

Excrete urea

Question 10

Kidney function 2

Answer 10

Control salt levels in blood, excess salt is excreted with the urine

Question 11

Kidney function 3

Answer 11

Control water level in your body

Question 12

Kidney cortex (renal cortex)

Answer 12

Contains tiny filtration units called nephrons

Question 13

Medulla

Answer 13

Contains funnels that drain urine from nephrons to the pelvis

Question 14

Kidney pelvis (renal pelvis)

Answer 14

Drains urine from the medulla to the ureter and bladder

Question 15

Urine

Answer 15

Waste material filtered out of the blood by the kidneys

Question 16

Urine contents

Answer 16

• 95% water
• 5% urea
• Small amounts of salts and pigment

Question 17

Urinary tract

Answer 17

System consisting of the kidneys, ureters , bladder and urethra

Question 18

Ureters

Answer 18

Long tubes that carry urine from the kidneys into the bladder

Question 19

Bladder

Answer 19

• A muscular pouch where urine is stored
• Can hold up to 500mL of urine

Question 20

Urethra

Answer 20

A tube that carries urine from the bladder out of the body