Nematoda

Bio 2.2 Zoology nematoda phylum

How do you identify the Nematoda?

the ecdyse.

Ecdysozoans

create an extracellular cuticle or exoskeleton that must be shed in order for the animal to grow.

Nematodes

roundworms

True or False: it is the most abundant animal on Earth

True

What is unique about the body cavity of Nematodes?

They have a body cavity that is pseudocoelom and develops from the embryonic blastocoel

What makes this cavity different from other animals?

They can use it as a hydrostatic skeleton, and organs are not suspended by any membranes

what is unusual about nematodes?

Muscle grows to the nerve cord, they only have longitudinal muscles. 

contrast nematodes and annelids

annelids have longitudinal and circular muscles allowing for peristaltic waves for movement

Nematodes have only longitudinal muscles so they observe a thrashing movement

Nematodes have a pseudocolem annelids have colemic cavity filled and serves as a hydrostatic skeleton

Compare nematodes and annelids

They both have a complete digestive system and a pharynx 

How can you tell this is a nematode?

due to its thrashing movements

Identify: Dorsal and ventral nerve cord, intestine, ovaries, uterus, and longitudinal muscles

refer to image.

What are the 7 reasons nematodes are worth paying attention too?

• nematodes are everywhere 

• they can reproduce a lot! store 20K eggs in their body at one time. they are hemaphrodites

• there is a lot of nematodes 4 out of every 5 animals are nematodes

• They are super old, date 400 mya, scientists think they have been around for billions of years 

• they are super basic but has some complexity 

• medical research, C. elegans share some biologistic characteristics to humans

• climate responds to temperature and are major players in the carbon cycle.