Excretion in Planaria, a type of flatworm, occurs through a specialized tubular excretory system known as protonephridia. This system consists of a network of closed tubules that are lined with flame cells, which have cilia that beat to propel interstitial fluid into the tubules. As the fluid moves through the tubules, waste products, primarily nitrogenous wastes, are filtered out and excreted through nephridiopores located on the body surface. This efficient system allows Planaria to maintain osmotic balance and remove toxic substances from their bodies, adapting well to their freshwater environments
What type of excretory system do Planaria possess?
Planaria possess a specialized tubular excretory system known as protonephridia
What are flame cells in Planaria?
Flame cells are specialized cells that line the protonephridia and have cilia that beat to propel interstitial fluid into the tubules
How do waste products get filtered in Planaria?
Waste products are filtered out of the interstitial fluid as it moves through the protonephridia and are excreted through nephridiopores
How does the excretory system of Planaria help maintain osmotic balance?
The excretory system helps maintain osmotic balance by efficiently removing excess water and toxic substances from their bodies
Where do the nephridiopores open in Planaria?
The nephridiopores open to the exterior on the body surface of Planaria
What type of excretory system do Planaria possess?
a) Metanephridia
b) Protonephridia
c) Malpighian tubules
d) Kidneys
Answer: b) Protonephridia
What are the specialized cells in Planaria's excretory system called?
a) Nephridia
b) Flame cells
c) Glomeruli
d) Nephrons
Answer: b) Flame cells
How do flame cells function in the excretory process of Planaria?
a) They absorb nutrients
b) They filter blood
c) They propel interstitial fluid into tubules
d) They store waste
Answer: c) They propel interstitial fluid into tubules
What type of waste do Planaria primarily excrete?
a) Urea
b) Uric acid
c) Ammonia
d) Creatinine
Answer: c) Ammonia
Where do the nephridiopores in Planaria open?
a) Into the digestive system
b) To the exterior of the body
c) Into the circulatory system
d) Into the coelom
Answer: b) To the exterior of the body