Animals: Higher Invertebrates
Annelida
Characterisitcs
-True coelom
-Coordinated digestion -Nervous system with a single ventral nerve cord -Anterior brain -Circulatory system -Five hearts (aortic arches) -Respiration through skin in land forms via diffusion -Sexual reproduction -Limited regeneration -Unspecialized segmentation separated by septa -Specialized excretory units called nephridia in each segment -Protostomes -Muscle around the skin and gut -Triploblastic -Bilateral symmetry |
Lab Results
Earthworm Dissection Results
Analysis
1. The aortic arches or hearts
2. The worm consumes its food using its mouth found in the anterior region, and then is swallowed by the pharynx. The food will then travel through the esophagus into the crop where it is stored. Then the gizzard will grind up the food completely. The food enters the intestine so that the digested food can be absorbed and transported to the rest of the body. Finally, the left over waste is excreted through the anus on the worms posterior
3. The earthworm has a small brain found in the anterior region that is connected to a ventral nerve cord that runs throughout the body to connect senses
4. The nephridium. nephrostome, and nephridiopore
5. Soil can be found inside the earthworm but making an incision into the intestine (the black/brown substance)
6. Setae allow the worm to move through dirt as well as damp environments such as grass
7. The gizzard grinds the soil up to allow the small amounts of nutrients to be absorbed
8. All the segments will be repeating and identical (simple segmentation)
9. Ectoderm- formed skin and nervous system
Endoderm- formed the digestive system, inner organs, and the lining of the digestive tract
Mesoderm- formed muscle surrounding the gut (allows coordinated digestion) and reproductive organs
10. The nephridium functions to remove metabolic waste. The waste from the previous segment is transferred into the next segment via the nephrostome, the waste then travels through the nephridium and the waste is excreted via the nephridiopore
11. Similar- basic characteristics of annelids, need moisture for survival, true coelom, single ventral nerve cord, anterior brain, sexual reproduction, excretory units called nephridia, segmented
Different- sandworms are strictly marine, sandworms have modified setae called parapodia, sandworms have crude gills which is the beginning of a respiratory system
12. Leeches have suckers that contain anaesthetic and an anticoagulant to prevent blood from clotting and minimal pain to alert the host. Their digestive system also acts like an accordion to allow maximum blood to be consumed
Similar- have a coelom, segmented, anterior brain, sexual reproduction, need a nutrient source, complete digestive system
Different- leeches are ectoparasites, earthworms eat soil, leeches use blood for nutrition , earthworms do not need a "host"
2. The worm consumes its food using its mouth found in the anterior region, and then is swallowed by the pharynx. The food will then travel through the esophagus into the crop where it is stored. Then the gizzard will grind up the food completely. The food enters the intestine so that the digested food can be absorbed and transported to the rest of the body. Finally, the left over waste is excreted through the anus on the worms posterior
3. The earthworm has a small brain found in the anterior region that is connected to a ventral nerve cord that runs throughout the body to connect senses
4. The nephridium. nephrostome, and nephridiopore
5. Soil can be found inside the earthworm but making an incision into the intestine (the black/brown substance)
6. Setae allow the worm to move through dirt as well as damp environments such as grass
7. The gizzard grinds the soil up to allow the small amounts of nutrients to be absorbed
8. All the segments will be repeating and identical (simple segmentation)
9. Ectoderm- formed skin and nervous system
Endoderm- formed the digestive system, inner organs, and the lining of the digestive tract
Mesoderm- formed muscle surrounding the gut (allows coordinated digestion) and reproductive organs
10. The nephridium functions to remove metabolic waste. The waste from the previous segment is transferred into the next segment via the nephrostome, the waste then travels through the nephridium and the waste is excreted via the nephridiopore
11. Similar- basic characteristics of annelids, need moisture for survival, true coelom, single ventral nerve cord, anterior brain, sexual reproduction, excretory units called nephridia, segmented
Different- sandworms are strictly marine, sandworms have modified setae called parapodia, sandworms have crude gills which is the beginning of a respiratory system
12. Leeches have suckers that contain anaesthetic and an anticoagulant to prevent blood from clotting and minimal pain to alert the host. Their digestive system also acts like an accordion to allow maximum blood to be consumed
Similar- have a coelom, segmented, anterior brain, sexual reproduction, need a nutrient source, complete digestive system
Different- leeches are ectoparasites, earthworms eat soil, leeches use blood for nutrition , earthworms do not need a "host"
Mollusca
Characterisitcs
Squid Dissection Results
Analysis
1. Tentacles: longer, thinner, two found on each squid (ours lost one)
Arms: shorter, 8 found on each squid
Both: found on ventral surface, have suckers
2. Similar: large ventral muscular foot, visceral mass, tissue layer called the mantle
Different: bivalves have a pronounced shell, squid are predatory, bivalves are stationary, squid have vertebrate eyes, bivalves filter feed, squid are highly intelligent and are capable of learning
3. Our squid was a male since there was a milky coloured substance under the mantle. Females have a yellowish colour
4. Squid will catch their prey, use their tentacles/arms to bring the food towards its mouth, the beak will then tear chunks of food off, the food travels through the esophagus into the stomach, the stomach digests the food, the cecum will then absorb the nutrients, materials that are not needed are passed through the intestines to be compressed into solid waste, the solid waste then passes through the anus/funnel
5. It allows gas exchange (oxygen in, carbon dioxide out) to happen much faster
Arms: shorter, 8 found on each squid
Both: found on ventral surface, have suckers
2. Similar: large ventral muscular foot, visceral mass, tissue layer called the mantle
Different: bivalves have a pronounced shell, squid are predatory, bivalves are stationary, squid have vertebrate eyes, bivalves filter feed, squid are highly intelligent and are capable of learning
3. Our squid was a male since there was a milky coloured substance under the mantle. Females have a yellowish colour
4. Squid will catch their prey, use their tentacles/arms to bring the food towards its mouth, the beak will then tear chunks of food off, the food travels through the esophagus into the stomach, the stomach digests the food, the cecum will then absorb the nutrients, materials that are not needed are passed through the intestines to be compressed into solid waste, the solid waste then passes through the anus/funnel
5. It allows gas exchange (oxygen in, carbon dioxide out) to happen much faster
Arthropoda
Characterisitcs
-Most dominant phylum (make up to 70% of animals)
-Exoskeleton made of hard chitin -Appendage formation -Respiratory system; tracheids (insects), book lungs (arachnids), and gills (aquatic varieties) -Highly specialized segmentation -Entirely sexual reproduction with separate sexes -Well developed senses -One ventral nerve -Small brain -Open type circulatory system (hemocoel/hemolymph) -Single heart -Bilateral symmetry -True coelom -Triploblastic Antennae (1 pair, 2 pairs in crayfish) -Walking legs |
Grasshopper Dissection Results
Crayfish Dissection Results
Live Organism Results
Echinodermata
Characterisitcs
-Deuterostomes
-Marine only -Semi flexible endoskeleton of calcarious plates -Pentaradial symmetry -Reproduction mostly sexual -Some powers of regeneration -Water vascular system used for movement, feeding, and respiration -Tube feet used for movement and hunting -Two stomachs (cardiac/pyloric) -True coelom -Triploblastic |