Rat Dissection

Over the past week we have been learning about the different groups of vertebrates.  To end of the unit we learned about mammals.  This rat dissection ended it off by providing a very interesting and exciting way to observe the different systems in most mammals.  The purpose of this dissection was to further our knowledge even more than what we had learned from doing notes and questions in class.  Being able to see the actual organs in the rat was very helpful for me in terms of making sure I could understand how the systems would work.  In class we had been talking about different organs that these mammals have such as the diaphragm which helps with inhaling and exhaling.  When we opened up these rats we were able to see this muscle involved in the respiratory system.  Another part we learned about in class was the mammals 4 chambered heart.  Once we were able to open up the rat's ribs we could see its heart.  This was very cool.  Mammals have also developed lungs for breathing which we saw as well.  The rat dissection was a very interesting experience.  

1. Hands are the best tool in this dissection because it displays the tissue and organs more naturally.

    2.   The purpose of having different labels and titles for the dissection is so the person dissection has a clear idea of what they are looking at and where to cut the specimen.

    3.   The tail is different from the body because it is not completely covered with hair.  

   

    4.   The vibrasse on the rats nose area are used for feeling out their environment.     

    5.   Bilateral symmetry means that the organisms body parts are arranged so that it seems like there is an imaginary line going down the middle of the body and the body parts are repeated on each side.

    1.   The sphincter is in a round shape to contain the constriction in the area between the small intestines and the stomach.  It's purpose is to keep stomach acids from pushing into the esophagus.

    2.   The small intestine is smaller in diameter because that is where most of the digestion takes place and it needs a longer distance to be able to absorb as much nutrients as possible.

    3.   The function of the liver is to metabolize nutrients. filtering wastes from blood and converting waste into a disposable form.

    4.   The duodenum got it's name from the Latin word duodenum digitorum which means "twelve fingers breadth".

    5.   The function of the appendix is to help digest food and break it down with digestive enzymes.

    1.   The function of the rats spleen is to clean out any foreign or waste products in the blood.

    2.   The contraction and expansion of the lungs allow air into the lungs and allow it to push carbon dioxide out.

    3.   The atria are the smaller parts at the top of the heart that holds the blood before it goes into the ventricles.  The ventricles then pump the blood out to the body.

    4.    The walls of the left ventricle are thicker than the right because it pumps the most blood out to the body; whereas, the right only pumps to the lungs. 
   
    5.    Both male and female reproductive systems have 2 chambers to hold either their sperm or their eggs and they both have a urethra.

    6.   The kidneys in rats remove waste and regulate the amount of water contained in the body.

    7.   The thyroid, thymus and adrenal gland are all part of the endocrine system which helps regulate the hormones and chemicals in the rats body.  The thyroid gland controls body growth and metabolic rate.  The function of the thymus is to turn lymphocytes to T-cells so they can help fight infections.  The function of the adrenal gland is to increase blood sugar levels when necessary and tell the kidney to absorb more sodium from the blood.     

Invertebrate Project

Grimpoteuthis

Dumbo Octopus

 

Phylum: Mollusca

Class: Cephalopoda

• Protosome 
• Bilateral symmetry
• 3 germ layers

Essential Functions

Body Structure:

• Ear-like fins on top of the head
• 8 tentacles connected by webbing
• Tentacles have 1 row of suckers and 2 rows of cirri (fleshy spikes) 
• Dumbo octopus can grow to 20-30cm long

Digestion (Feeding):

• Grimpoteuthis eat crustaceans, worms, bivalves and small fish
• They hover over the bottom and use their tentacles and cirri to get food into their mouth
• Their radula is reduced or totally gone
• Therefore, they swallow prey whole!

 

Circulatory:

• All octopi have 1 main heart and 2 smaller ones near their gills
• The smaller ones pump blood to the gills and pump blood with oxygen to the main heart
• Octopus blood has hemocyanin which makes it blue instead of hemoglobin that would turn it red

Respiration:

• The Dumbo octopous respire the same way as other octopi, they use gills to get oxygen from the water
• As the oxygen passes over the feathery gills it gets passed into the blood and transported trhough the body

 

Excretion:

• The Dumbo Octopus has an anus to release solid waste
• They also have nephridia that collect fluids, concentrate them and put them with the other waste going out the anus
  

Movement:

• They hover over the sea floor
• To move they expand and contract their webbed arms
• They are also able to shoot water through their funnel 
• They can also flap their fins on their head

Reproduction:

• Females lay eggs all year round, have no specific breeding season
• They lay their eggs under rocks and leave them to fend for themselves
• Males have a large segment on their arm to transfer sperm packet (spermatophore) into female mantle cavity
• Packet ruptures when it enters and fertilizes the eggs

Another organism in the phylum Mollusca is the squid.  Squids are similar to octopus because they are both in the class Cephalopoda.  They both have arms with suckers on them however, squids also have two long tentacles that they use to capture their prey.  They also have a closed circulatory system filled with hemocyanin similar to octopi.  Both cephalopods squirt out ink when they feel endangered.  Squids and octopus can both move by jet propulsion but the dumbo octopus has fins on its head that it uses to swim as well. 

Interesting Facts:

• Dumbo Octopus can be found from 400m - 4800m deep in the ocean
• The largest one ever found was about 6 feet long and weighed 13 lbs.
• There are 37 known species of the Dumbo Octopus

I love this Invertebrate because of it's interesting appearence and it's unusual resemblence to the Disney character Dumbo.



 

Squid Dissection

On Friday December 7 we go to dissect squids in class.  This experiment allowed us to locate major organs inside and outside of the squid and examine the squids features.  In class we had been learning about different mollusks and their body parts and different behaviours.  We had learned about the three main classes of mollusks which include Gastropods, Bivalves and Cephalopods.  The Gastropod class included snails and slugs, the Bivalve class includes clams and oysters and the Cephalopods include octopi and the squid we dissected.  We learned that all mollusks are composed of three parts; the visceral mass, the foot and the mantle.  When we opened up the squids we were able to see all of these parts.  On the outside of the squid we saw the arms that the squids use to take in food and that surround a strong beak that they use to tear their prey.  In class we learned about how squids shoot out a cloud of ink when they feel threatened and when we dissected the squid we found the ink sac and used the ink to write with, almost like a pen.  Dissecting the squid was helpful for me in some ways since it did provide a visual aid for my learning but since not all the squids were completely mature some of the body parts were missing so we couldn't see them.

External Anatomy Questions

1.) Our squid had eight arms and two tentacles.       

2.) The arms have sucking disks on them so they are used to grab their prey.  The long tentacles also have suckers but only on the ends.  They are used to help eat prey.

3.)








4.) Two external features on the squid that are adaptions for the squids predatory life are that it can move quickly through jet propulsion and that it can squirt out dark ink.  Moving quickly is helpful for the squid because it can swim away from predators and escape if they can't swim as fast as it.  Being able to squirt out ink is a helpful adaptation because it can temporarily hide the squid or confuse the predator.






5.) Two general traits that squids share with other mollusks are that they all have trochophore larvae and their body forms are all similar; they all have a foot, shell, mantle cavity and visceral mass.





Internal Anatomy Questions

1.) The squid had one pair of gills.       

2.) The ink sac empties into the funnel and is squirted out when the squid is scared to try and get away from predators.









3.) The pen supports the structure and without it the squid wouldn't be able to hold its shape and it would collapse in on itself.









4.) Waste goes into the anus and then gets emptied into the water jet which releases the waste outside the body.

Annelid (earthworm) Dissection

Last Friday on November 30th our Biology class got to dissect earthworms. Between each pair we got one worm and we had to pin it down and carefully slice it open so we could investigate the parts inside. Having us observe the inside of real earthworms was an interactive and exciting way for us to learn more about how the digestive, nervous, circulatory and reproductive systems work and what they really look like. After doing this dissection I found that I had a better understanding of segmented worms and it was a good learning tool in addition to the information we had learned in class. In class we had learned about the different parts of the digestive system such as the mouth, the esophagus, the pharynx, the crop, the gizzard, the intestine and the anus. When we opened up the worm we were able to see all of these parts and the track that the food and soil it ate would travel. We had also learned about it's circulatory system in class. We found out that they have five "hearts" or pairs of aortic arches and these we found inside the body as well. In our notes we learned the biological role of earthworms and how they are composters that help turn organic matter into fertile soil. When we opened the worm my partner and I opened up the intestine and we could see the soil that was travelling towards the anus and being turned into a fertilizer. At first I found cutting open an earthworm a little bit gross but seeing all the knowledge we had learned happening inside this body really helped me understand the information more.

1. The pumping organs of an earthworm are pairs of aortic arches, or hearts.

2. The earthworms food enters through the mouth, goes into the pharynx, enters the area between the pharynx and the crop which is called the esophagus, then it enters the crop where the food is stored for a little while, next it is broken up in the gizzard, then it goes through the intestine where it's body absorbs the nutrients and lastly the waste passes through the anus.

3. There is one pair of ganglia above the pharynx which act as the brain of the earthworm and are connected to the rest of the body by the ventral nerve chord.






4. The two parts of the earthworms excretory system that we saw were the nephridia and the anus.




5. To find out if an earthworm eats soil you can open up the intestine and see what is inside of it.





6. The setae help with the earthworm's movement through their dirt environment. Without the setae they wouldn't be able to move very well.



7. The earthworm's digestive system is able to absorb all the nutrients from the food it eats and turn the soil and other waste into a fertilizer.


8. If we were to dissect the earthworm to the posterior end we would have seen the remainder of the intestine, the anus, the rest of the ventral nerve chord and some of the nerves coming off of it.





9. Earthworms are hermaphroditic, they contain both eggs and sperm. When they are ready to be released from the body the eggs exit through the female genital pores and e sperm go through the male genital pores. Each worm has a clitellum which protects the eggs in a cocoon structure. When an earthworm wants to reproduce they attach to another worm and exchange sperm, which travels into the seminal receptacles of its mate

Overall, we were able to find organs from the reproductive, digestive, nervous and circulatory system. Seeing all these systems for real put all the facts we had learned about earthworms into an accurate.

Zoology Webquest

Staurocalyptus
Phylum: Porifera
Genus: Acanthascus
Destributed through California, Southern Californina Bight and Northern Pacific Ocean




Chrysaora fuscescens
Phylum: Cnidaria
Genus: Chrysaora
Species: C. fuscescens
Catch their prey with nematocyst laden tentacles
Can reprodeuce sexually in the medusa stage and asexually in the ployp stage

 

Pseudobiceros bedfordi
Phylum: Platyhelminthes
Genus: Pseudobiceros
Species: P. bedfordi
Foundin Malaysia, Australia and Indonesa
Delicate creatures with ribbon-like, oval-shaped bodies

Vancouver Aquarium Adventure

On Thursday November 22 our class took a field trip to the Vancouver Aquarium.  While we were there we conducted an experiment with snails to try and determine what they eat, we got to touch and learn about different sea creatures and also look around at all the species of animals there were at the aquarium.  We went near the end of the week after we had been learning about different animals from different phylums that live in the ocean.  We had learned about sponges from the phylum Porifera and a variety of jellyfish from the phylum Cnidaria.  On our trip to the aquarium we were fortunate to see both of these magnificent animals.  We went on this trip to try and acquire new knowledge about these amazing creatures and to also provide a kinesthetic environment for learning.  On our behind the scenes look at the tanks of sea anemones, sea stars and hermit crabs we got to see how the animals would behave in their natural habitat which I know helped me make connections to what we are learning in class.  Having the leaders explain to us about the species in each tank also taught us more in addition to the knowledge we already had from class.  My favourite part of thee whole trip was getting to touch the sea anemones and the sea cucumbers and see how they would react if another animal would touch them.  The sea anemones that we got to touch didn't have enough venom in them to sting us badly but when we did touch them they felt sticky.  I also liked holding the sea urchins and seeing the difference in their structure between when you held them out of water and then inside the water.  Another creature I really enjoyed looking at was the sea stars because when I held one in my hand it slowly molded its body to the shape of my hand the way it would if it was sitting on the side of a rock, which I found really neat.

The Clown Fish and the Sea Anemone have a symbiotic relationship, which means they both benefit.  The Clown Fish scares off any other fish that might try and eat the anemone and it also drops bits of food that the anemone picks up, while the stinging tentacles of the anemone provide protection for the Clown Fish.



Otters spend so much time cleaning their coats because that is what allows them to survive in the chilly waters that they live in.  Their thick layer of fur traps the air and insulates the otter.

 

Before the year 1900 sea otters could be found in the North Pacific Ocean and more specifically near Alaska and California. However, the sea otters were being hunted for their fur before the 1900's so there weren't alot of otters in the world. In the early 1900's people were banned from hunting otters and around the1960's and 1970's sea otters started to be reintroduced to Alaska and California.



The colour of the sea anemones beside the sea otters tank is red, green and purple.

 



In order to protect themselves jellyfish have structures in the end of their tentacles called nematocysts which sting any predators that might try and eat them.  Jellyfish also use these nematocysts to attack their prey which they will sting and eat.  To move around, jellyfish use their long tentacles to propel themselves as well as contracting the muscles in their bell-shaped body to create a jet-like propulsion.  Another adaptation that allows jellyfish to survive is that they are mostly made up of water so they can float easier.



The scientific name of beluga whales is Delphinapterus leucas.  There are two at the Vancouver Aquarium currently.



The seahorses that we saw at the Aquarium weren't Potbelly Seahorses but they still made a flicking motion with their tail in order to move themselves around.

 



To blend in with their background Starry Flounder have pigment cells that allow them to change colour and camouflage with their surroundings.  Another adaptation they have developed is that their tail moves in a lateral motion.  This allows it to throw sand or mud over itself in an attempt to hide from predators.  

 

Moon jellies shoot themselves through the water but pumping there bodies and pushing the water.  Some say the way they move is almost rhythmic like.  In order to catch the plankton for food the Moon Jellies have developed a mucus that the plankton land on and get stuck in. 

 

The purpose for the white suction cups on the arms of the octopus is that they contain nerves and they can also taste with the suction cups.  Octopus's are very intelligent and they also have sharp beaks inside their mouths that they use to tear into the flesh of their prey.  The bite of an octopus is also venomous. 

Stellar Sea Lions eat mostly squid, fish or invertebrate.  Some of the fish they eat are herring, salmon, pollock and cod.  Each day sea lions have to eat at least 6% of their body weight.
 

The Caimans came from Central and South America.




The crocodiles at the aquarium were a dark green and brown colour.  This colouring helped them camouflage in their environment and hide from predators.



The largest fish in the aquarium is an Arapaima and it is 4.5 m.




The vegetarian fish in the Amazon is a Pacu also known as a "Vegetarian Piranha".  These fish feed mainly on insects, fruits and nuts.




Piranhas are the biggest threat during dry seasons when all the piranhas have eaten the fish in their area and have to try and find a new food source, which sometimes ends up being humans.



Sharks have no bones in their bodies.  They are made out of cartilage instead.

 

Also found in the shark tank are sting rays and other small fish.



The Giant Red Sea Urchin is scientifically known as Strongylocentrotus franciscanus.  In order to hold themselves down the giant red sea urchin has tube feet that hold it to the ground and stable it so it doesn't get swept away by the current.



When Archerfish see an insect they would like to catch and eat they shoot up a spout of water and try to knock it down in the water.



The name of the sea turtle in the Tropic Zone at the Vancouver Aquarium is Schoona.