Phylum Platyhelminthes ("flat worms")

Question 1

Protostome or Deuterostome?

Answer 1

1. Protosome

Question 2

Dipl or Tripl?

Answer 2

2. Triploblastic; acoelomate

Question 3

Digestion

Answer 3

• incomplete digestive tract*
• missing an anus & series of specialized organs for digestion
  
  • *except Cestoda

Question 4

Respiration

Answer 4

• No obvious respiratory organs
• flat bodies → high surface area to volume ratio

Question 5

Symmetry

Answer 5

• bilateral symmetry – identical left & right sides
• have cephalization – collection of neurons at the anterior end

Question 6

Excretion

Answer 6

• excretion via protonophridia (aka flame cells)
  
  • creates a current towards the exit outside the body
• inside → outside & takes toxins w/ it

Question 7

Level of Organization

Answer 7

• organ-system level of organization
• bring in food & convert it to nutrients

Question 8

Nervous

Answer 8

• nerve system: nerve network & ganglia (collection of nerve tissue)
• nerve impulse processed at ganglia & it determines the response

Question 9

Body shape?

Answer 9

dorso-ventrally flattened

Question 10

Reproduction

Answer 10

monoecious (male & female reproductive parts)

Question 11

Parasitic or free-living?

Answer 11

Either or

Question 12

They are “Lophotrochozoa”

What does that mean?

Answer 12

triploblastic, non-molting (don’t have to take off outside to grow)