First final question

Within the animal kingdom we have dissected a roundworm (phylum nematoda), an earthworm (phylum annelida), a grasshopper (phylum arthropoda), a starfish (phylum echinodermata) and a grass frog (phylum vertebrata, class amphibia).
I will be discussing each of these dissections.

Roundworm:



Feeding and Digestion

• Roundworms have 2 openings(mouth and anus)
• Mouth contains 3-6 rows of teeth
• The food enters through the mouth, then into the pharynx, and then, the very long intestine. This extends all the way to the anus, where the food is eliminated.
  

  

Reproduction

• These are the intestines from the roundworm
• Male roundworms produce sperm in a long thin tube called the testes
• Fertilization is internal
• The female roundworm produces egg cells within the very thin, coiled ovary
• Fertilization takes place inside of the female

Respiration, circulation, nervous system

• Don't have a proper circulatory or respiratory system
• Diffusion takes place in body walls
• The 2 nerve cords in the roundworm are dorsal nerve cord and ventral nerve cord. They transmit impulses to various cells and tissues of their bodies

Earthworm:

 

 

Feeding/Digestion

• 2 openings, mouth and anus
• They use the pharynx to bring in the food, then the food passes the esophagus and goes into the crop, the gizzard grinds it up and moves the food into the large intestine.

Reproduction

• Hermaphrodites(contain male and female parts)
• Internal reproduction
• clitellum is used in its reproduction

Respiration, circulation, nervous system

• diffusion takes place in body wall.
• contain spiracles instead of lungs
• closed circulatory system
• have series of muscular vessels called hearts
• aortic arches pumps blood into other 2 vessels
• dorsal blood vessels carry blood to front of the body
• ventral blood vessels carry blood to the back of the body
• primitive brain, ventral nerve cord receive info and control body

grasshopper:





 

Feeding/Digestion

• 2 openings
• uses mandible and two pairs of maxillae for feeding. 
• 3 main digestive parts are foregut, midgut, and hindgut

Reproduction

• internal reproduction
• ovipositors store the eggs
• newborns often shed skin(metamorphosis)

Respiration, circulation, nervous system

• openings called spiracles that have tubes that are the respiratory system
• no lungs
• has a heart which circulates blood
• open circulatory system
• has a brain, nerve cord, and sensory organs

starfish:

feeding/digestion

• Complete digestion system with a mouth , two stomachs, an intestine, and an anus
• it uses its digestive glands called pyloric caeca
• when feeding the starfish stomach pops out and sucks in the food
• excretes waste through anus

reproduction

• Hermaphrodites
• external reproduction in water
• reproductive organs calles gonads in its arms
• reproduce asexually by Binary Fission

Respiration, circulation, nervous system

• ampulla, which are bulbs on the inside of its arms used for respiration and circulation
• no lungs
• closed circulatory system
• water vascular system
• no brain
• eyes on each arm 

Grass frog:

Feeding/digestion

• very similar to us
•  digestive system consists of a stomach, small intestine, large intestine, and anus
• feed on insects such as flies, etc.

Reproduction

• females have a thin string which is called the oviducts
• Reproduction has to take place in water because tadpoles can only swim
• external fertilization

Respiration, circulation, nervous system

• has lungs
• respiration also takes place through their skin
• closed circulatory system
• has a heart and many blood vessels
• has a brain
• nervous system is very similar to humans nervous system