How do Tuck and Roll behave? --- Animal Behavior Lab Report

Linfei Liu 

A Block Hon. Bio
04/14/14

How do Tuck and Roll behave? --- Animal Behavior Lab

ABSTRACT:
In this lab, our task is to find out what environment the terrestrial isopods (pillbugs / roly-polies) prefer to live by observing their behaviors. We collect ten pillbugs and put them in a choice chamber, where two petri dishes of the same size are joined together. Throughout the lab, the environment of the two sides of the choice chamber will be different from each other in only one aspect, while other conditions of two sides remain constant. We will observe and record the data in every thirty seconds for a five-minute-long period. After counting the number of pillbugs on the two sides and analyzing the data, we are able to find out what kind of environment is more preferable to pillbugs.
INTRODUCTION:
To understand the purpose of this lab, we need to first comprehend these following concepts:
1. Behavior simply means everything an animal does and how it does it. Behavior is the range of actions and mannerisms made by organisms or systems in conjunction with themselves or their environment, which includes the other systems or organisms around as well as the (inanimate) physical environment. It is the response of the system or organism to various stimuli or inputs. In other words, behavior is the internally coordinated responses (actions or inactions) of whole living organisms (individuals or groups) to internal and/ or external stimuli. Furthermore, Behavior can be either innate (inherited) or learned. Behavior can be regarded as any action of an organism that changes its relationship to its environment. Behavior provides outputs from the organism to the environment. Also, behaviors may be innate or learned. Many behaviors have both genetic and learned components.

2. Usually, there are two types of explanations and questions for behaviors: 1) Proximate explanation / question relates to how the behavior occurs. Proximate explanation / question focus on the environmental stimuli that trigger the behavior. 2) Ultimate explanation / question relates to why the behavior occurs. Ultimate explanation / question addresses the evolutionary significance of the behavior. For example, a proximate question about bird song would be “How does the bird know when it is the right time to sing?” and an ultimate question about bird song would be “Why does the bird sing?” “What is the purpose of the song?”

3. As mentioned before, there are two types of behaviors. One type is innate behavior; the other type is learned behavior. Innate behavior is inborn and cannot be modified; furthermore, innate behavior is developmentally fixed and under strong genetic influence. Some innate behaviors (especially instincts) followed fixed action patterns (FAP). Fixed action pattern is a sequence of unlearned behavioral act that is essentially unchangeable and, once initiated, is usually carried to completion. It is triggered by an external sensory stimulus (sign stimulus.) FAP is highly stereotyped behavior. An example of fixed action patterns would be in male stickleback fish, the stimulus for attack behavior is the red underside of an intruder. When presented with unrealistic models, as long as some red is presented, the attack behavior occurs. Another fixed action pattern shared by some animals, including humans, is yawning, which often triggers yawning in other individuals. Yawns last around six seconds and are difficult to stop once initiated. 

RED!! Intruder! ATTACK!!

Triggers yawning in other individuals :P  So cute!

Aww! So cute!

4. Furthermore, orientation behaviors, a type of innate behaviors, are series of coordinated movements that are triggered in a particular direction by environmental stimuli. These behaviors include kinesis and taxis movements. The kinesis movement is a simple change in activity or turning rate in response to a stimulus; moreover, the pace of the motion is directly proportional to the intensity of the stimulus. An example of kinesis movement is woodlice prefer damp condition. If the environment is too dry, they will move more often, although in random directions, until they find moist areas. In this case, the movement is non-directional and random. Instead of moving towards or away from the stimulus, the organism simply moves more, or less in response to a stimulus. In comparison, the taxis movement is a more or less automatic, oriented movement toward or away from an environmental stimulus. An example of taxis movement would be many stream fish exhibit a positive taxis and automatically swim in an upstream direction. This taxis movement prevents then from being swept away and keeps them facing the direction from which food will come. The taxis movement is directional. A positive taxis would be a directional movement towards the environmental stimuli, and a negative taxis would be a directional movement away from the environmental stimuli.

Stream fish 

5. On the other hand, learning behavior is the modification of behavior based on specific experiences. Learned behaviors include imprinting, classical conditioning, operant conditioning, habituation and insights. Imprinting behavior occurs as an animal matures, it may form social attachments to other individuals or form preferences that will influence behavior later in life. Imprinting is a behavior that includes learned and innate components and is generally irreversible. It is distinguished from other learning by a sensitive period. A sensitive period is a limited developmental phase that is the only time when certain behaviors can be learned. An example of imprinting would be young geese following their mother goose. Another example is that Konrad Lorenz showed that when baby geese spent the first few hours of their life with him, they imprinted on him as their parent. A proximate cause for their imprinting behaviors may be that during their early development stage, the mother of young geese choose to move away from the young geese and call them to begin the learning routine. The ultimate cause of those imprinting behaviors may be that young geese mimic the actions of their mother to learn necessary skills, walking and hunting and so on, to survive in their habitat.

6. As mentioned before, there are two types of learning behaviors for animals. One type is classical conditioning, also known as associative conditioning. Classical conditioning is the repeated presentation of a stimulus in association with a response that causes the brain to form an association between the stimulus and the response, even if they have never been associated before. One classic example of classical conditioning is an experiment done by Ivan Pavlov. In his experiment, the dog would drool when food is provided and has no reaction to the tuning fork before conditioning. During the conditioning, Pavlov would provide food to the dog after he rings the tuning fork. Thus, after the conditioning, the dog would drool when it hears the tuning fork. Pavlov’s experiment successfully proves that the dog that repeatedly hears a tuning fork before being fed will salivate in anticipation at the tuning fork’s sound through conditioning or repeated events. Another type of learning behavior is operant conditioning. Operant conditioning is a type of learning behavior in which an animal learns to associate one of its behaviors with a reward or punishment. It is also called trial-and-error learning (it is really similar to classical conditioning). An example of operant conditioning would be a predator might learn to avoid a specific type of prey associated with a painful experience.

Overall, classical conditioning is a type of learning which forms an association between two stimuli. Operant conditioning is a type of learning that forms an association between a behavior and a consequence. 

Poor dog going through associative conditioning

Operant Conditioning

Classical Conditioning

7. Additionally, habituation is a simple form of learning that involves loss of responsiveness to stimuli that convey a little or no information. For example, birds will stop responding to alarm calls from their species if these are not followed by an actual attack. Habituation is a form of learning, a diminishing response to a repeated stimulus. On the other hand, instinct is an inborn pattern of activity or tendency to action common to a given biological species.

Pillbug’s Background Information
“In this lab, we will be working with terrestrial isopods commonly known as pillbugs, sowbugs, or roly-polies. These organisms are members of the Phylum Arthropoda, Class Crustacea, which also includes shrimp and crabs. Most members of this group respire through gills (Source from AP Lab 11: Animal Behavior / Experimental Design handout)”.

QUESTIONS: 

Are the behaviors of pillbugs that are displayed in the choice chambers taxis or kinesis? Do pillbugs prefer living in a moist and high pH level environment or a dry and low pH level environment?

HYPOTHESIS:
Part One: 

If the pillbugs are given a choice to stay either in a dry chamber or a wet chamber, then by the end of the lab, the majority of pillbugs will choose to stay in the wet chamber (pillbugs in the dry one will find their way to the wet chamber). The reason that this phenomenon occurs is because pillbugs are naturally inhabited in moisture areas. Furthermore, if the pillbugs choose to stay on the same side, then the behavior is taxis because the pillbugs move toward a stimulus, moisture. As “in taxis, the animal moves toward or away from a stimulus. Taxis is often exhibited when the stimulus is light, heat, moisture, sound, or chemicals” (Source from AP Lab 11: Animal Behavior / Experimental Design handout).

Part Two: 

If the pillbugs are put in two environments with different pH level (One chamber has nothing in it, the other chamber has vinegar in it), then most of the pillbugs will move to the chamber without vinegar in it, because the pH level of pillbugs’ natural inhabitation is high, which means it’s basic instead of acidic. A high pH level environment is necessary for pillbugs' survival in their habitat as they are mostly found under rocks or in the soil. On the other hand, if the majority of pillbugs choose to stay on the same side, then the behavior is taxis because the pillbugs act in a uniform way away from the stimulus.

Our independent variable in Part One is the difference in moisture on either side of the choice chamber, and our dependent variable of Part One is the amount of pillbugs on either side. In Part One, our constants of the lab are the total number of pillbugs, the same surface level, the temperature, the pH level, the intensity of light exposure, the intensity of heat and the sizes of both the two circular spaces of the choice chambers and filter paper. On the other hand, our independent variable in Part Two is the difference in pH level on either side of the choice chamber, while our dependent variable is the amount of pillbugs on either side. In Part Two, our constants of the lab are the same surface level, the total number of pillbugs, the temperature, the amount of moistness, the intensity of heat, the intensity of light exposure and the sizes of both the two circular spaces of the choice chambers and filter paper. 

METHODOLOGY:
MATERIALS:
Two choice chambers
Two pieces of filter paper
Ten pillbugs
A lamp
Two data sheets
A paintbrush
A timer
A beaker with 50 mL of water
A beaker with 50 mL of vinegar
Two plastic pipets (use to absorb the liquid)
Plastic wrap or petri dish cover
Writing utensils and paper

PROCEDURE:
1. Place 10 pillbugs in a choice chamber. They generally try to get out so cover the chamber with plastic wrap or a petri dish cover.

2. Observe the pillbugs for ten minutes. Make notes on their general appearance, movements about the chamber, and interactions with each other. Notice if they seem to prefer one area over another, if they keep moving, settle down or move sporadically. Note any behaviors that involve 2 or more pillbugs. Do not interfere with the specimens in any way.

3. Make a detailed sketch of a pillbug.

4. Prepare the other choice chamber and place a filter paper on either side.

5. Place one side of the chamber under a bright lamp and cover the other side with a plastic wrap of some sort or another choice chamber.

6. Choose your variables to be tested: Moisture, light, and set up the adjacent room accordingly. Use a soft brush / paint brush to transfer the ten pillbugs into the second choice chamber. Cover the chambers being used.

7. Count how many pillbugs are on each side of the choice chamber every 30 seconds for 5 minutes. Record down the data in a table. Continue to record even if they all move to one side or stop moving.

8. When done recording, return the pill bugs into the stock choice chamber.

9. Graph both the number of pill bugs in the wet/ with vinegar chamber and the number in the dry/ without vinegar chamber.

The set-up

The set-up

Image from: local.brookings.k12.sd.us/krscience/.../LAB%20DATA/.../lab%2011.pdf‎

Image from: local.brookings.k12.sd.us/krscience/.../LAB%20DATA/.../lab%2011.pdf‎

Image from: local.brookings.k12.sd.us/krscience/.../LAB%20DATA/.../lab%2011.pdf‎

Image from: local.brookings.k12.sd.us/krscience/.../LAB%20DATA/.../lab%2011.pdf‎

Image from: http://local.brookings.k12.sd.us/krscience/protected/LAB%20DATA/11pillbugs/lab%2011.pdf

RESULTS: 

Part One

Part Two

Part One: Wet VS. Dry

Time (Minutes)	Number of Pillbugs in Wet Chamber	Number of Pillbugs in Dry Chamber
0	5	5
0.5	5	5
1.0	6	4
1.5	6	4
2.0	7	3
2.5	7	3
3.0	7	3
3.5	7	3
4.0	7	3
4.5	6	4
5.0	7	3

Part Two: with Vinegar VS without Vinegar

Time (Minutes)	Number of Pillbugs in Chamber with vinegar	Number of Pillbugs in Chamber without vinegar
0	0	10
0.5	2	8
1.0	2	8
1.5	2	8
2.0	1	8
2.5	1	8
3.0	1	8
3.5	1	8
4.0	1	8
4.5	1	8
5.0	1	8

CONCLUSION:
  As mentioned in the introduction, this lab focuses on the behavioural responses of pillbugs. Our task is to figure out what kind of environment is more preferable to pillbugs. Moreover, throughout the lab, we learn that the pillbugs are to respond in a taxis manner in both parts of our experiment. Taxis behavior occurs when the animal is moving toward or away from a stimulus. In order to achieve an accurate result, we keep all variables constant except the independent variables and dependent variables in both parts of the experiment.
  In both parts of the experiment, the pillbugs react in a taxis manner. From the graphs above, the lines show a steady increase or decrease (depends on the variables) For Part one, it shows that the pillbugs prefer the moist choice chamber, while in Part Two, it shows that the pillbugs prefer the high pH level chamber. Despite the trend that a few pillbugs stay in the opposite chamber throughout the experiment, overall, the majority of the pillbugs prefer the moist and high pH level side of the choice chamber, which proves our hypothesis to be correct. Therefore, we can conclude that the pillbugs prefer to live in moist and high pH level environment than dry and low pH level environment. Although the experiment was successful, sources of error might have occurred: 1) we might have mis-counted, or counted too late when the time is up during the experiment. 2) For Part Two, up to two minutes, sadly, one of the pillbugs died. The loss of this one particular pillbug affects our total number of the pillbugs and the constant of the experiment. 3) The filter paper is not completely soaked with vinegar at first, and we change it after we start timing.

CITATION:
"Animal Behavior Chapter 51." Animal Behavior Chapter 51. N.p., n.d. Web. 11 Apr. 2014.

AP Lab 11: Animal Behavior / Experimental Design handout, Kevin Quick, Mar. 2014. 

Dusenbery, David B. (2009). Living at Micro Scale, p. 124. Harvard University Press, Cambridge, Mass. ISBN 978-0-674-03116-6.

Levitis, Daniel; William Z. Lidicker, Jr, Glenn Freund (June 2009). "Behavioural biologists do not agree on what constitutes behaviour". Animal Behaviour (78).

ADDITIONAL INFORMATION:
1. Link to a video explaining this lab and the concepts in introduction http://www.bozemanscience.com/ap-bio-lab-11-animal-behavior/

2. Link to a lab practice
http://www.phschool.com/science/biology_place/labbench/lab11/control.html

This is how we roll! ;)

Immune System Quiz

The Question - QUIZ
An important defense against disease in vertebrate animals is the ability to eliminate, inactivate, or destroy foreign substances and organisms. Explain how the immune system achieves all of the following.
1) Provides an immediate nonspecific immune response
2) Activates T and B cells in response to an infection
3) Responds to a later exposure to the same infectious agent
4) Distinguishes self from nonself

General Idea --- What is immune system:

I. The purpose of the immune system is to keep infectious microorganisms, such as certain bacteria, viruses, and fungi, out of the body, and to destroy any infectious microorganisms that do invade the body. The immune system is made up of a complex and vital network of cells and organs that protect the body from infection.

II. The organs involved with the immune system are called the lymphoid organs, which affect growth, development, and the release of lymphocytes (a certain type of white blood cell). The blood vessels and lymphatic vessels are important parts of the lymphoid organs, because they carry the lymphocytes to and from different areas in the body. Each lymphoid organ plays a role in the production and activation of lymphocytes. 

Lymphoid organs include:

• adenoids (two glands located at the back of the nasal passage)
• appendix (a small tube that is connected to the large intestine)
• blood vessels (the arteries, veins, and capillaries through which blood flows)
• bone marrow (the soft, fatty tissue found in bone cavities)
• lymph nodes (small organs shaped like beans, which are located throughout the body and connect via the lymphatic vessels)
• lymphatic vessels (a network of channels throughout the body that carries lymphocytes to the lymphoid organs and bloodstream)
• Peyer's patches (lymphoid tissue in the small intestine)
• spleen (a fist-sized organ located in the abdominal cavity)
• thymus (two lobes that join in front of the trachea behind the breast bone)
• tonsils (two oval masses in the back of the throat)

Lymphoid organs

1. Provides an immediate nonspecific response

For immune system, there are physical, chemical and cellualr defenses against foreign invasions, such as viruses, bacteria, and other agents of disease. During the early stages of an infection, there is an inflammatory repsonse (aka nonspecific response)

• Non-specific attack
• Phagocytes active ("eat" pathogen)

Nonspecific Response is our second line of defense. it provides us immediate defense against pathogen infection. It does noe target a speicific cell. The elements of the non-specific immune system include anatomical barriers, secretory molecules and cellular components. Among the mechanical anatomical barriers are the skin and internal epithelial layers, the movement of the intestines and the oscillation of broncho-pulmonary cilia. Associated with these protective surfaces are chemical and biological agents.

Anatomical barriers to infections
The epithelial surfaces form a physical barrier that is very impermeable to most infectious agents. Thus, the skin acts as our first line of defense against invading organisms. Also, movement due to cilia or peristalsis helps to keep air passages and the gastrointestinal tract free from microorganisms. The flushing action of tears and saliva helps prevent infection of the eyes and mouth as fatty acids in sweat inhibit the growth of bacteria, and lysozyme and phospholipase found in tears, saliva and nasal secretions can break down the cell wall of bacteria and destabilize bacterial membranes. The trapping effect of mucus that lines the respiratory and gastrointestinal tract helps protect the lungs and digestive systems from infection. 

B. Humoral barriers to infection
The anatomical barriers are very effective in preventing colonization of tissues by microorganisms. However, when there is damage to tissues the anatomical barriers are breached and infection may occur. Once infectious agents have penetrated tissues, acute inflammation defense mechanism would then kick in. Humoral factors play an important role in inflammation, which is characterized by edema and the recruitment of phagocytic cells. These humoral factors are found in serum or they are formed at the site of infection.

Table 2. Physico-chemical barriers to infections
System/Organ	Active component	Effector Mechanism
Skin	Squamous cells; Sweat	Desquamation; flushing, organic acids
GI tract	Columnar cells	Peristalsis, low pH, bile acid, flushing, thiocyanate
Lung	Tracheal cilia	Mucocialiary elevator, surfactant
Nasopharynx and eye	Mucus, saliva, tears	Flushing, lysozyme
Circulation and lymphoid organs	Phagocytic cells NK cells and K-cell LAK	Phagocytosis and intracellular killing Direct and antibody dependent cytolysis IL2-activated cytolysis
Serum	Lactoferrin and Transferrin	Iron binding
	Interferons	Antiviral proteins
	TNF-alpha	antiviral, phagocyte activation
	Lysozyme	Peptidoglycan hydrolysis
	Fibronectin	Opsonization and phagocytosis
	Complement	Opsonization, enhanced phagocytosis, inflammation

C. Cells for nonspecific response 

Phagocytes - cells which "eat" foreign material to destroy them
Phagocytes are formed from stem cells in bone marrow (stem cells are undifferentiated WBC's) 

Neutrophil- phagocytize bacteria. Polymorphonuclear cells are recruited to the site of infection where they phagocytose invading organisms and kill them intracellularly. In addition, PMNs contribute to collateral tissue damage that occurs during inflammation.
Eosinophils - secrete enzymes to kill parasitic worms among other pathogins. Eosinophils have proteins in granules that are effective in killing certain parasites.  

Macrophage - "big eaters" phagocytize just about anything. Tissue macrophagesand newly recruited monocytes, which differentiate into macrophages, also function in phagocytosis and intracellular killing of microorganisms. In addition, macrophages are capable of extracellular killing of infected or altered self target cells. Furthermore, macrophages contribute to tissue repair and act as antigen-presenting cells, which are required for the induction of specific immune responses.
Natural killer (NK) and lymphokine activated killer (LAK) cells – NK and LAK cells can nonspecifically kill virus infected and tumor cells. These cells are not part of the inflammatory response but they are important in nonspecific immunity to viral infections and tumor surveillance. 

Macrophage destroying bacterial cells

2. Activates T and B cells in response to an infection
T cells (Helper T cells and Cytotoxic T cells)
T cells arise from stem cells in the bone marrow, and then travel to the thymus where the differentiate and mature. At maturity, they acquire receptors for self markers (MHC molecules) and for antigen-specific receptors. They are then released into the blood as "virgin" T cells.
T cells ignore other cells with MHC molecules and they ignore free-floating antigens. However, they will bind with a antigen-presenting macrophage (a macrophage possessing a MHC-antigen complex). This binding promotes rapid cell division and differentiation into effector and memory cells (all with receptors for the antigen).
Effector helper T cells secrete interlukins (stimulate both T and B cells to divide and differentiate).
Effector cytotoxic T cells recognize infected cells with the MHC-antigen complex. They then destroy the cell with perforans (enzymes which perforate the cell membrane, allowing cytoplasm to leak out) and other toxins which attack organelles and DNA.

B cells and Antibodies
B cells also arise from stem cells in the bone marrow. As they develop and mature, they start synthesizing a single type of antibody.
Antibodies are proteins which recognize antigens.
The virgin B cell produces antibodies which move to the cell surface and stick out.
The B cell floats in the blood when it encounters the specific antigen it becomes primed for replication.
The B cell must receive an interleukin signal from a helper T cell which has already become activated by a macrophage with a MHC-antigen complex. This promotes rapid cell division.
The B cell population then differentiates into effector and memory B cells.
The effector B cells then produce a staggering amount of free-floating antibodies.
When these free-floating antibodies encounter an antigen, they tag it for destruction by phagocytes and complementary proteins.

*ADAPTIVE immunity = highly specific for a particular pathogen / antigen.

Antigen presenting cells present foreign antigen on their surface.

• Antigen is recognized by T and B cells.
• Cytotoxic T cells kill infected cells.
• Helper T cells Activate Macrophages, T and B cells.
• B cells produce AntiBodies.
• AntiBodies bind to antigens and bring about: 
• Neutralization: pathogen can’t adhere to host cell
• Opsonization: makes it easier for phagocytosis
• Complement activation: kills infected cell by punching holes in cell membrane.
• Memory cells are made that are much more efficient (does NOT need T cell activation) in proliferating and making antibodies in case the same infection strikes in the future.
• Memory cells allow the body to mount a greater, and more sustained response against the same pathogen during secondary response.

3. Responds to a later exposure to the same infectious agent
Immune memory --- when an antigen makes contact for the first time with cells of the humoral immune system, B lymphocytes that are producers of specific immunoglobulins against that antigen multiply and in days synthesize their antibodies. This is called primary response. Some of these specific B lymphocytes remain in the circulation for a long time, sometimes during the entire life of the individual, and they become the memory cells of the immune system. T cells can also produce memory cells with an even longer life span than B memory cells. When the body is exposed in the future to the same antigen, B and T memory cells help the immune system to activate much faster, and the production of antibodies will be faster and more intense since the immune system is already prepared to react against that antigen. This is called the secondary response. 

Examples of this phenomenon could be chicken pox and cancer. As we known, if a person had chicken pox before, that person is most likely never getting chicken pox again. The same goes for who had the immunization of chicken pox. Also, when fighting cancer, our immune system undergoes the same mechanism. When one's body is exposeed to cancerous cells, one's immune system would remember these cancerous cells and recognize these cells next time. However, if one happens to develop cancer, one's imuune system is probably being worn out.  

4. Distinguishes self from nonself

One of the most essential abilities of the immune response is the ability to distinguish between "self" and "non-self." Every cell in one's body carries the same set of distinctive surface proteins that distinguish one as "self." Normally one's immune cells do not attack one's own body tissues, which all carry the same pattern of self-markers; rather, one's immune system coexists peaceably with one's other body cells in a state known as self-tolerance. This set of unique markers on human cells is called the major histocompatibility complex (MHC). There are two classes: MHC Class I proteins, which are on all cells, and MHC Class II proteins, which are only on certain specialized cells.

Any non-self substance capable of triggering an immune response is known as an antigen. An antigen can be a whole non-self cell, a bacterium, a virus, an MHC marker protein or even a portion of a protein from a foreign organism. The distinctive markers on antigens that trigger an immune response are called epitopes. When tissues or cells from another individual enter your body carrying such antigenic non-self epitopes, your immune cells react. This explains why transplanted tissues may be rejected as foreign and why antibodies will bind to them.

Every cell in one's body is covered with these MHC self-marker proteins, and--except for identical twins--individuals carry different sets. MHC marker proteins are as distinct as blood types and come in two categories--MHC Class I: humans bear 6 markers out of 200 possible variations; and MHC Class II: humans display 8 out of about 230 possibilities ( National Cancer Institute 2014).

Summary
Immunity can be either natural or artificial, innate or acquired=adaptive, and either active or passive.
Active natural (contact with infection): develops slowly, is long term, and antigen specific.
Active artificial (immunization): develops slowly, lasts for several years, and is specific to the antigen for which the immunization was given.
Passive natural (transplacental = mother to child): develops immediately, is temporary, and affects all antigens to which the mother has immunity.
Passive artificial (injection of gamma globulin): develops immediately, is temporary, and affects all antigens to which the donor has immunity. 

Sources from:
Mr. Kevin Quick, Lecture at The Webb Schools, 2014.
http://thelifeofapremed.tumblr.com/post/56690250816/leukocytes-macrophages-neutrophils-mast-cells
http://pathmicro.med.sc.edu/ghaffar/innate.htm
http://www.cancer.gov/cancertopics/understandingcancer/immunesystem/AllPages
http://www.uic.edu/classes/bios/bios100/lecturesf04am/lect23.htm
http://www.course-notes.org/Biology/Outlines/Chapter_43_The_Immune_System 

http://en.wikipedia.org/wiki/Polyclonal_B_cell_response

No love for Pineapple --- The Jell-O Lab

Linfei Liu
A Block Hon. Bio
02/16/14

No Love For Jolly Pineapple (Enzyme’s effectiveness in Relation to Temperature) 

                                                                                                                        -- The Jell-O Biology Lab

ABSTRACT:
For this lab, we explored the properties of the enzyme, Bromelain, in relation to temperature and how temperature could affect the function of Bromelain; furthermore, we figured out the relationship of Bromelain and Jell-O formation. During this lab, we discovered that temperature could change the shape of Bromelain; thus, temperature could affect the function of enzyme, namely Bromelain in this lab. Also, we found out that Bromelain would become ineffective and unable to break down the collagen of the Jell-O at high temperatures. This discovery confirms our prior knowledge of the characteristics of enzymes that enzymes function properly under certain circumstances, such as optimal pH level and temperature.

INTRODUCTION

QUESTION:
Why does it say on the directions “Do not use fresh or frozen pineapple, use cooked or canned”? What is the difference? Why would it matter? What does Jell-O have in it? What does pineapple have in it that doesn’t mix?

 
BACKGROUND:
Bromelain is a natural enzyme that could be found in the juice, stem, and fruit of the pineapple. The enzyme, Bromelain has been used as a digestive enzyme to aid the internal organs in digestion. Also, it is an anti-inflammatory enzyme as it is used for reducing swelling (inflammation), especially of the nose and sinuses, after surgery or injury. Furthermore, Bromelain supplements are promoted as an alternative remedy for various health problems including joint inflammation and cancer. Bromelain has been used for hundreds of years in folk medicine. As mentioned before, this type of enzyme would affect the formation of Jell-O. Bromelain contains two enzymes that have the ability of breaking down proteins called proteases. Jell-O, a type of gelatin, structures itself by form links between chains of collagen. However, Bromelain could cut these chains of collagen and keep the gelatin from being jelly properly. Fresh pineapple does this as a natural self-defense. Whereas canned pineapple is heated during the canning process. Thus, the enzymes in Bromelain in the pineapple are inactivated as their optimal temperature of functioning is changed to about 158° F. This is the reason why Jell-O needs to be formed by using canned pineapple.

HYPOTHESIS:
If we use canned pineapple, which is already heated, Jell-O will form. Yet, other types of pineapple would not work, such as frozen pineapple and fresh pineapple. 

METHODOLOGY
MATERIALS:
· 6.69g of Jell-O powder
· 39.4mL of hot water
· 39.4mL of cold water
· 2.4g frozen pineapple
· 2.4g canned pineapple
· 2.4g fresh pineapple
· 4 petri plates with covers
· 3 graduated cylinders
· 3 stirring rods
· 1 refrigerator
· 1 hot plate
· 1 beaker

PROCEDURE:
1. Boiling an amount of water greater than 80mL in a beaker on the hot plate.
2. Prepare the variables, such as frozen pineapple, canned pineapple juice, and fresh pineapple juice.
3. Put these variables into their own petri plate and label them
4. Make a control plate (no pineapple presented in the plate)
5. Pour 6.6 g of Jell-O powder into the beaker
6. Add 39.4 mL of boiling water into the beaker, and mix the powder and the water well with the stirring rod.
7. For each plate, evenly distribute 10mL of hot water, 10mL of cold water, 1.65g of Jell-O powder, and 1mL of the pineapple juice (depends on the plate, pour in different type of juice or pour in nothing).
8. Cover all the petri plates and carefully label each one of them.
9. Bring the petri plates to the refrigerator and begin cooling.
10. Allow the Jell-O to settle, come back next day to check the data.

Canned Pineapple---formed Jell-O 

Canned Pineapple

Fresh Pineapple --- nothing 

Frozen Pineapple --- nothing

Control Plate (no pineapple) --- formed Jell-O

RESULTS:

Plates	Set	Liquid	Jell-O formation
Control (No pineapple)	Yes	No	Successful
Jell-O with frozen pineapple	No	Yes	Fail
Jell-O with canned pineapple	Yes; yet, not as firm as the control plate	No	Successful
Jell-O with fresh pineapple	No	Yes	Fail

As shown in the graph, Jell-O is formed in the control plate and the plate with canned pineapple juice, and the plate with frozen pineapple juice and the plate with fresh pineapple would not form Jell-O.

CONCLUSION:
As mentioned in the hypothesis, if we use canned pineapple, which is already heated, Jell-O will form. Yet, other types of pineapple would not be able to make Jell-O become set, such as frozen pineapple and fresh pineapple. In relation to our hypothesis, our final result fails to reject our hypothesis. While the Jell-O containing fresh pineapple/ frozen pineapple did not become set, the canned pineapple formed Jell-O. Our testing result supports our hypothesis. The lab result is successful. Therefore, when Jell-O mixes with the pineapple that still containing Bromelain, Jell-O would not be set properly as Bromelain would break Collagen Bonds. Nevertheless, when Jell-O mixes with heated pineapple (canned pineapple), Jell-O would form properly due to the reformation of the collagen bond’s shapes and active site. Bromelain is inactive in the canned pineapple. During this lab, we also set up a control plate with nothing in it but Jell-O (this is the regular plate), and we kept the amount of hot water, the amount of cold water, the amount of Jell-O powder, and the amount of the juice to be constant. Also, we kept the temperature during the Jell-O- formation period to be the same, since all the plates were placed in the same fridge. Although our final result is successful, there are still some sources of error as well as human error:
1) Inaccurate measurement of the amount of necessities that we need for the lab may cause some errors.
2) False measurement of the amount of product.
3) Need to do more trials to confirm a more accurate result.
4) Could have tested other fruits to check the result.
5) Contamination of different types of pineapples
6) Crossing contamination of Bromelain.
Last but not least, through this lab, we have learned a critical characteristic of enzymes -- the effect of temperature on the function of enzymes. 

CITATION:
American Cancer Society (2001, April 06). Bromelain. Retrieved from http://www.cancer.org/treatment/treatmentsandsideeffects/complementaryandalternativemedicine/herbsvitaminsandminerals/Bromelain
Mr. Kevin Quick, Lecture at The Webb Schools, 2014.
Natural Medicines Comprehensive Database (2013, April 24). Bromelain. Retrieved from http://www.nlm.nih.gov/medlineplus/druginfo/natural/895.html