Comparative: Crayfish Vs. Worm

Crayfish
Nervous System: 

• Made up of ganglion  which are connected by a circumoral commissures with the post oesophageal ganglia

Habitat:

• Crayfish live in water, which is classified as an aquatic environment. They are found in oceans and ponds.
• They hide from the predators in the deep ocean water, under rocks and in dark places.

Movement:

• Crayfish have an external skeleton and move by using there swimmerets.

Reproduction:

• Male crayfish attaches sperm underneath females belly. The female then uses her tail to attach the eggs to her swimmerets 

Worm:

Nervous System:

• Brain is connected to ventral nerve cord

Habitat:

• live in soil, found sometimes in grass, mud and gardens.

Movement:

• Earthworms move using there cilia and contracting there muscles. They have a hydrostatic skeleton.

Reproduction:

• Hermaphrodites, meaning both male and female - but can't produce with themselves.

Comparative Vertebrate Post

The Digestive System:

The digestive system is the chemical breakdown of food into smaller components that are more easily absorbed into the blood stream.

Rat Digestive System


As humans we have similarities to the rat digestive system. They are listed as the following:


Similarities 
Three main areas of digestive system: salivary glands, oral cavity and the abdominal cavity.


There are also differences between Rat and human digestive system:


Differences
We as humans have gall bladder and rats don't. Rats instead have a bile duct which is formed with tubes to the liver.


Below is a picture of my rat dissection, it shows parts of the digestive system.



Respiratory System
The respiratory system of rat and human are very similar except for a few minor differences. They both use the system to exchange carbon dioxide and air.

Similarities
four chambered heart,
Differences:
Rats hearts take more breaths per minute than humans because their hearts beat faster.

What I Learned Today: Worm Sort

For the worm sort, I looked at four different types of worms. Each worm belongs to a classification. The worms I looked at were: Lumbricus earthworm, aempais leech, polynoe scale worm, calcareous tube worm. The classifications that they all could belong to are the following: Flat worm, round worm, tape worm and segmented worm.

Lumbricus earthworm - Segmented worm

Aempais leech - Segmented worm

Polynoe scale worm - Segmented Worm

Calcareous tube worm - Round Worms

CHARACTERISTICS/FACTS OF FLAT WORM:

-Spaghetti shaped, thin, solid bodys
-14500 species of flatworms
-Found in marine fresh water

CHARACTERISTICS/FACTS OF ROUND WORM:

- Nematoda Phylum
- Lives in soil, animals, fresh water
- Lacks circular muscles, have length wise muscles

CHARACTERISTICS/FACTS ON SEGMENTED WORM:

- Annelida Phylum
-Two body openings
-Body is a tube with in a tube
-Tiny bristles

CHARACTERISTICS/FACTS ON TAPE WORM:

- Flat bodies
- bilateral symmetry


Below is a picture of a tapeworm