Frog Dissection Lab

Picture from:

 http://animals.nationalgeographic.com/animals/amphibians/amazon-horned-frog/

In this lab we did on Monday and Tuesday was dissecting a frog. On the first day we cut open the skin on the ventral side. What we found out was that underneath that layer of skin is a layer of muscle tissue. After that we opened up the muscle tissue and saw the organs. What we first saw was the liver. The liver is the biggest organ in the body and produces bile for digestion. Since we had a male frog we didn't have any eggs so it was easier for us. We also found the fat bodies. Then we located the heart which is next to the liver. Next was the gall bladder, it is located underneath the liver and holds the bile being created. We found the lungs which was found underneath all the organs. Next to that was the pancreas. That produces enzymes for digestion.
        Then next to the spine was the kidneys. They filter the bodies blood. We learned how close the frog's system is like ours. We learned in class that the frogs reproduction system isn't efficient because so many eggs or tadpoles(baby frogs)die from being eaten. We also found out the reason why the mouth part of the frog expands. The reason why being the lung expanding when breathing. The systems are very similar to our systems like the digestive system. Like the order. It goes from the stomach through the small intestine to the large intestine. If you get lucky you can cut open the stomach and might see what the frog ate last. The frog is a really interesting species, the reason why I think they are such a interesting animal is because they are so simalar to the human.

You can learn more about the frog here: http://www.lookd.com/frogs/anatomy.html and for the digestive system here: http://www.tutorvista.com/biology/frog-digestive-system-diagram.



Picture from:

http://www.photographyblogger.net/21-cool-frog-pictures/



Picture From:
http://www.e-tutor.com/et3/lessons/view/52133/print





Immune System Game

Click here for larger version

Digestion Lab Response Blog

What we did in this lab was work with two types of acid. We were showing how digesting works like how the acid in our stomach breaks down the food. We had 4 beakers, we labeled them A B C D. A just had pepsin, B had Pepsin and water. C had just hydrochloric acid. D is a mix of Hydrochloric acid and Pepsin. We put 3 pieces of eggwhites inside each beaker. A and C are controls. They were just to see how they worked by themselves. On day 1 we checked if there were any imediate reaction. All of the beakers didn't have a reaction. That showed that digestion doesn't happen quickly. Also we tested if they were acidic. A and B were not but C and D are. The next day nothing happened for all of them except D. In the beaker D the eggs got smaller. Then we checked if it got more or less acidic. A and B were not acidic but C was very acidic and D was very acidic to. At the end of the day we tested there ph and B was less acidic then distilled water. C was more acidic than B. Last was D which was really acidic. The most acidic.

Chicken response

What occurd during the lab was we took off the skin and looked at the muscle. Then we took the muscle off and saw the ligaments. After that we saw the cartilage connecting the two bones. Then we cut open the bone and saw the bone marrow. In the lab we observed how similar the chicken wing and the human arm are. We saw how everything was connected to something. Like how the muscle tissue is connected to the bone. We also learned that when one muscle is contracted then the other is relaxed. Like when the tricep was being pulled (contracted) the bicep was relaxed and vice versa. We learned that ligaments connect to muscles together. Also that cartilage is inbetween to bones to prevent damage of them rubbing together.

Iodine Lab

We poured 100 ml. of water inside the plastic bag. Then got one spoonful of starch into the bag. We filled the beaker half way with water and put iodine inside. We put the bag inside the beaker and waited. After 15 min. the starch didn't change at all. We put in more iodine and waited another 5-10 min. Then we checked the bag again and the bottom of the starch was purple. The whole purpose of the lab was to show that the cell membrane (bag) lets certain things through (iodine). We were showing that iodine can go through the "cell membrane" and change the starch. So in the end we learned that cell membranes are semi permeable.