Tuesday, January 24, 2012

Vertebrate comparitve study

During class we dissected a rat and a frog, using the information gathered from these dissections we could see the comparisons and the differences between these vertebrates. 

Comparison of Circulatory system of Rat and Frog

The circulatory system of the Rat and the Frog include; The heart, the artery's, the capillary's and the veins.  on all 4 of these I will do a comparative study in the next section. the circulatory system in the Rat and Human are the same.

Heart:

The heart is used to pump blood at high pressure though the artery's, the higher the pressure that the blood goes though the artery's and the cappilary's the higher the rate of diffusion. So the higher the pressure that your heart can transport blood through your circulatory system the better but this comes at a cost, a more efficient and complex heart requires more energy to work.












The reason chose this picture is because                                      The reason I chose this picture is  
it clearly shows the frogs heart.                                                  because the heart is clearly visible


Similarities:
  • Both have 2 Atria which pump blood into ventricle(s) 
  • Both have 2 exits out of heart, 1 going to the lungs and 1 going to the body
  • Both have a closed circulatory (cardio vascular) system, this means that blood cycles through the entire body without leaving the cardio vascular system, while in some animals the blood is dumped onto the organs like a bathtub. 


Diffrences:
  • a Frog has a 3-chambered heart while a Rat has a 4 chambered heart, a 4 chambered heart is way more efficient because this way the oxidized blood is kept separate from the deoxidized blood. 
  • a Frogs heart has 1 ventricle where both the oxidized and deoxidized blood go through (the frogs heart does have a way to make its heart more efficient and that is by having the left and the right atria pump the blood through the ventricle just a tiny bit off set) , while the Rat has 2 ventricles so the blood never mixes.
  • The septum in the heart of the Rat creates this sepertation between oxidized and deoxidized blood.
  • The Frogs heart requires less energy to work then the Rats because of its simplicity.



Blood vessels

  • Artery's are huge blood vessels that carry massive amount of blood, the blood carried by artery's is mostly oxidized one of the exceptions it the artery that carries deoxidized blood to the lungs. All the blood vessels that carry oxidized blood come from the artery's.
  • Capillary's are extremly small blood vessels, they are so small that blood cells have to travel single file through them. Capillary's are everywhere in the body because they provide the nutrients and oxygen to every cell.
  • Veins carry mostly oxygen free blood back to the heart. Veins carry the oxygen free blood into the right atrium where it is pumped to the ventricles and then pumped through the lungs to get oxidized once again.















I couldn't find a picture in our dissection                         The probe is holding up an artery which is                                                                  
that showed the veins so i picked this one.                                           why i picked this picture.  
















The veins in this picture are clearly visible                 As you can see in this picture the veins in the  
which is why I picked this picture.                                     rat are not nearly as visible as in the frog.


Similarities:
  • Both have a main artery coming out of the hearts right side carrying oxidized blood.
  • Both have a artery going to the lungs from the top of the heart carrying deoxidized blood.
  • Both artery's carrying oxygen rich blood out of the body are called the Aorta.
  • Capillary's in both Rat and Frog perform the same functions
  • Veins in Frog and Rat perform the same functions

Diffrences:
  • Blood vessels in the frogs skin are much more visible then those in the Rats skin. this is because it is ectothermic so it is constantly exchanging heat with it surroundings.  



Comparison of Respiratory system of Rat and Frog

The respitory system includes; the nose, mouth, lungs and trachea. on all 3 three of these i will do a comparative study in the next section. The Human respiratory system in mammals is the same so everything that is true for the rat is also true for a Human.


Respiratory system

  • The nose and mouth are key parts to an animals respiratory system simply because of the fact that this is where the animal acquires its oxygen from by breathing.
  • The trachea commonly known as the windpipe connects the nose and mouth to the lungs where it branches and enters both lungs, any damage done to this tube can have severe consequences because this is the only way for oxygen to get to the lungs
  • The lungs consist of 2 parts one to the right of the heart and one to the left, each lung is divided into lobes, the right lung has 3 lobes while the left one has only 2. 













This is the clearest picture i could find                                  this picture shows the Left and
that showed the lungs of a Frog                                                   Right Lungs of the Rat



Similatities:
  • Both have a trachea.
  • Both Frog and Rat have lungs.
  • Both have nostrils.
  • The function of the respiratory system in both these animals is to supply the body with oxygen rich blood.


















I chose this picture because it clearly shows                this was the only picture i could find that 
the nostrills and the glottis of the Frog.                                showed the mouth of a Rat


Diffrences:
  • Frogs have a moist skin though which diffusion occurs.
  • The lungs in a Frog are much simpler then those in a Rat this is less efficient but since Frogs are able to use diffusion through their skin they do not requires such efficiency. 
  • In Rats breathing causes ribs to expand to a certain degree.This is because mammals have a diaphragm, Frog are unable to expand their ribs because of this lack of a diaphragm.
  • Because frogs are cold blooded they do not require as much oxygen as warm blooded animals like Rats.
  • When frogs are in their tadpole state they have gills to allow them to breathe underwater.
  • Frogs pull oxygen through their nostrils into mouth by lowering the bottom of its mouth from there the oxygen goes through the glottis and into the trachea.
  • Since Frogs do not require as much oxygen as Rats they have less aveoli in they're lungs





Refences:
I used my notes for  most of the presentation but I did use some information of the internet on the topics that my notes did not fully cover.

Saturday, January 21, 2012

crayfish/worm comparative study

Movement:

Crayfish:
  • crayfish have jointed appendages
  • crayfish have swimmets which allow them to swim 
  • legs enable walking on land
Worm:
  • worms do not have legs to walk
  • every segment on a worm is a muscle
  • by contracting and expanding these muscles the worm is able to move
Excretory system:

Crayfish:
  • the excretory system is located near the eyes
  • have green gland near the base of the large antennae
  • have excretory pore
Worm:
  • have 2 niphridia in every segment
  • these connect to pores which get rid of the waste
  • worms have 1 long digestive track which starts at the mouth and goes all the way back to the anus
Reproduction:

Crayfish:
  • are either male or female
  • gonads are located dorsal side of the thorax
Worm:
  • worms are hermaphrodites (have both sexes)
  • they cross fertilize
  • they mate by attaching clitella and exchanging sperm
  • reproductive organs are found in section 9 and 10
Habitat:

Crayfish:
  • live in water
  • have gills to enable breathing underwater
  • have swimmets to enable movement underwater
Worm:
  • live in soil
  • prostonium at the mouth closes when the worm isnt feeding to prevent soil from entering worm
  • have circular muscles to enable movement through soil