The Pill Bug's Optimal Living Environment

The Pill Bug’s Optimal Living Environment

Abstract:

            In this lab, we observed the change in behavior of 10 pill bugs, when they were placed into a black and white environment. We experimented with the pill bugs preference for colors. We did so by placing a dry white paper into one dish of the choice chamber (two connected dishes) and a dry black paper in the other dish. We placed the 10 pill bugs into the dish and covered them. We removed the other choice chamber every 30 seconds to observe the pill bugs behavior and their preference for colors. We found that the majority of the pill bugs preferred a dark environment over a white one.

 

Question:

            How do the pill bugs react to changes in its environment?

 

Background:

            Behavior is the way an organism behaves or acts. Proximate questions about behavior are questions that focus on the physical mechanics of the behavior and the environmental factors that trigger a behavior (“how” questions). Ultimate questions are questions that focus on how evolution has created the behavior (“why” questions). An example of a proximate question is how does a bird know when it is the right time to sing? An example of an ultimate question is why does the bird sing?

Fixed action patterns are an innate behavior (unlearned and developmentally fixed behavior), a sequence of unlearned and mostly unchangeable acts triggered by sign stimuli. An example of a fixed action pattern is migration and the waggle dance.

 Imprinting is a mix of learned and innate behavior, it is limited to a certain sensitive period of an organism’s life. An example of imprinting is when a goose after hatching follow its mother. The young geese adapt to the environment where its mother goes and also the movement of its mother. The geese do what its mother does. The proximate cause would be, during the early and important developmental period, young geese observe their mother moves and calling. The ultimate cause would be, the geese who follow their mother will acquire the necessary skills for survival than those who do not follow their mother.

There are two types of innate behavior: kinesis and taxis. Kinesis behavior is a simple change in behavior in response to stimuli. An example of kinesis behavior is a sow bug that moves from a dry open area to a more preferable moist site under a leaf. Taxis behavior is an automatic movement from or to a stimuli. An example of taxis behavior is a trout fish will move against the direction of the current because most of the food comes in that direction.

Kinesis Behavior

 

Taxis Behavior

Classical and operant conditioning are two important concepts of behavioral psychology that lead to learning by different processes. Classical conditioning was first described by Ivan Pavlov, a Russian psychologist. The classical conditioning shows automatic and involuntary behavior that results from placing neutral signals before a reflex. In an experiment, Ivan Pavlov would play music when he would feed the dogs, he did so for a period of time. Than when the music was played without the food the dogs began to salivate because they were expecting food. The music in this case would be the conditioned stimulus, the salivating would be the condition response, and the food would be the unconditioned response.

Classical Conditioning

Operant conditioning was first described by B.F. Skinner, an American psychologist. Operant conditioning includes reinforcement or punishment after a behavior which leads to strengthening or weakening of voluntary behavior. An example is rewarding a dog through praise for a behavior such as fetching a ball, when the dog fails to retrieve the ball withhold the praise. Eventually the dog forms a relation between the behavior and the wanted reward.

Operant Conditioning

 

Hypothesis:

            If 10 pill bugs are placed into a choice chamber, one dish with white, dry paper (control) and another dish with black, dry paper (control), then the pill bugs will prefer the darker environment because their natural habitat (underneath rocks) is a dark environment.

            The controls are the dry paper of the same size, and the choice chambers. The dependent variable would be the number of pill bugs that prefer the dark environment and the number of pill bugs that prefer the light environment.  The independent variable would be time.

 

Materials:

·         2 choice chambers

·         10 pill bugs

·         1 circular dry white paper

·         1 circular dry black paper

·         1 paint brushes

·         1 timer

·         1 data sheet

 

Procedure:

1.      Find and Collect 10 pill bugs

2.      Place pill bugs into a choice chamber

3.      In another choice chamber, in one dish place a dry circular black paper and in the other dish place a dry circular white paper

4.      Gently place the pill bugs into the new chamber by using a paint brush

5.      Cover the new chamber with the old choice chamber

6.      Every 30 seconds remove the cover chamber and record your data

7.      And repeat step 6 for 5 minutes

 

 

Results:

 Black Paper and White Paper columns' units are number of pill bugs

 

  Orange line: white paper

                                                           Blue line: black paper

 

Conclusion:

            Our hypothesis is correct since the data shows that the majority of pill bugs moved to the darker paper rather than the white paper, because the darker paper resembles their natural habitat (underneath rocks) where we found and collected them. In nature the darker environment was protection from predators because the pill bugs could camouflage into the environment and hide from predators, this adaptation was developed through evolution. The constants of this lab was the dry environment and the choice chambers. One potential source of error is incorrectly recording your data by mixing columns. Another source of error would be not giving enough time for the pill bugs to move and choose the color they prefer.

Citations:

Cherry, Kendra. "Classical vs Operant Conditioning." About.com Psychology. N.p., n.d. Web. 01 Apr. 2014. <http://psychology.about.com/od/behavioralpsychology/a/classical-vs-operant-conditioning.htm>.

 

"Imprinting." - Definition from Biology-Online.org. N.p., n.d. Web. 03 Apr. 2014. <http://www.biology-online.org/dictionary/Imprinting>.

 

"Quizlet." Chapter 51: Study Questions~Behavioral Ecology Flashcards. N.p., n.d. Web. 03 Apr. 2014. <http://quizlet.com/16596812/chapter-51-study-questionsbehavioral-ecology-flash-cards/>.

 

 

Immune System Quiz

1.      Non-specific responses are generalized responses to pathogen infection - they do not target a specific cell type. The non-specific response consist of some white blood cells and plasma proteins

List of strategies

                                                              i.      Physical barriers- uses skin and mucous membrane to prevent foreign substances from entering the body

                                                            ii.      Phagocytes- cells which "eat" foreign material to destroy them

1.      Phagocytes are formed from stem cells in bone marrow (stem cells are undifferentiated white blood cells)

2.      Nuerophils , Eosinphils, and macrophages are also used

a.       Neurophils-phagocytize bacteria

b.      Eosinophils-secrete enzymes to kill parasitic worms among other pathogens

c.       Macrophages-"big eaters" phagocytize just about anything

 

Macrophage destroying bacterial cells http://www.uic.edu/classes/bios/bios100/lecturesf04am/lect23.htm



 

                                                          iii.      Immunological surveillance- uses natural killer cells

                                                          iv.      Interferon-uses interferons (chemical messengers)

                                                            v.      Complement- uses a group of proteins that can attach to pathogens and antigens

                                                          vi.      Inflammatory response- uses mast cells, and basophils to release histamine which increases local blood flow

1.      Mast cells-similar to basophils, mast cells contain a variety of inflammatory chemicals including histamine and seratonin.  Cause blood vessels near wound to constrict

2.      Basophils-contain granules of toxic chemicals that can digest foreign microorganisms.  These are cells involved in an allergic response

                                                        vii.      Fever-Increased body temperature due to antibodies or chemicals released by macrophages or pathogens

 http://www.uic.edu/classes/bios/bios100/lecturesf04am/lect23.htm

 

 

2.      There are two types of T cells, helper cells which help B cells, and Killer Cells which kill foreign substances. The T cells are activated when a phagocyte eats a foreign substance and takes it to the spleen to identify what the foreign substance is. The T cells make an antigen that binds to the foreign substance so the B cells can "kill" the foreign invader.

a.       Helper T cells - produce and secrete chemicals which promote large numbers of effector and memory cells

b.      Cytotoxic T cells - T lymphocytes that eliminate infected body cells and tumor cells

c.       B cells - produce antibodies (secrete them in the blood or position them on their cell surfaces

 

 

 

3.      Same process except it is faster than previously. The immune system creates memory B cells that remember the foreign substance and it begins immune responses to fight off the infectious agent that it has encountered before.

 

4.      Each type of virus, bacteria, or other foreign body has molecular markers which make it unique

a.       Host lymphocytes (i.e. those in your body) can recognize self-proteins (i.e. those which are not foreign)

b.      When a non-self (foreign) body is detected, mitotic activity in B and T lymphocytes is stimulated

c.       While mitosis is occurring, the daughter populations become subdivided

d.      Effector cells - when fully differentiated, they will seek and destroy foreign

e.       Memory cells - become dormant, but can be triggered to rapid mitosis if pathogen encountered again

Glucocorticoids

1.      Natural glucocorticoids are produced in the cortex of adrenal gland

2.      Glucocorticoids are steroid hormones. Natural steroid hormones are generally synthesized from cholesterol in the gonads and adrenal glands. These forms of hormones are lipids. They can pass through the cell membrane as they are fat-soluble, and then bind to steroid hormone receptors which may be nuclear or cytosolic depending on the steroid hormone, to bring about changes within the cell.  The glucocorticoid receptor is cytosolic

3.      Steroid hormones are not water soluble. Glucocorticoids are lipid soluble so they have to be carried in the blood complex to specific binding globulins.  

4.      Steroid hormones are nonpolar (no net charge), and can thus diffuse across lipid membranes (such as the plasma membrane).  They leave cells shortly after synthesis. Polar substances are water soluble (dissolve in water), nonpolar substances are lipid soluble. Making it a Plasma membrane receptor.

5.      Glucorticoids have a negative feedback loop because the product of the reactions interrupts the activity of the enzyme producing the product.

6.      The name “glucocorticoid” derives from early observations that these hormones were involved in glucose (sugar) metabolism. During times when no food is being taken into the body, glucocorticoids stimulate several processes that serve to increase and maintain normal glucose concentrations in the blood. These processes include:

·         Stimulation of glucose production in cells, particularly in the liver.

·         Stimulation of fat breakdown in adipose (fat) tissues.

·         Inhibition of glucose and fat storage in cells.

They affect all types of inflammatory responses, regardless of the mode of injury or type of disease-causing substance.

7.      The receptors in target molecules need to be suitable for the signaling molecule for glucocorticoids

 

Podcast

Citations:
http://www.stanford.edu/group/hopes/cgi-bin/wordpress/2010/06/glucocorticoids/
http://en.wikipedia.org/wiki/Steroid_hormone

Generation of Carbon Dioxide from Various Carbohydrates

Abstract:

In this lab, we observed cellular respiration; we measured the amount of carbon dioxide produced from various carbohydrates when in contact with yeast. We used several different types of carbohydrates such as potato starch, honey, glucose, and cane sugar.  We used five test tubes, one of which was the control. Every test tube including the control contained 35 milliliters of lukewarm water, 1 gram of yeast, l gram of sugar, and 0.2 grams of salt. In each of the four test tubes we added different carbohydrates. The control was left untouched. We placed a rubber cork with a tube attached to a syringe (placed at l milliliter) in order to measure the amount of carbon dioxide produced. After shaking each tube to mix the contents thoroughly, we placed the tubes into a Styrofoam tube holder to control the temperature and labeled them according to their starch.  We then placed the corks on top and checked the syringe every minute for around 20 minutes to measure the amount of carbon dioxide produced.

 

Question:

Will different types of carbohydrates yield different amounts of carbon dioxide during cellular respiration?

 

Background:

The chemical formula for cellular respiration is: C₆H₁₂O₆ + O₂ → CO₂ + H₂O + Energy (ATP). Cellular respiration occurs in the cytoplasm and mitochondria. Cellular respiration is a metabolic process by which food molecules are converted into energy. This process uses carbohydrates, fats, and proteins. But glucose is most commonly used. Cellular respiration consists of three processes: glycolysis, Krebs cycle, and oxidative phosphorylation. Glycolysis occurs in the cytosol, the 6-carbon sugar breaks into 2 molecules of 3-carbon molecules called pyruvate. This process produces 2 ATP and 2 NADH molecules. In the Krebs cycle occurs in the mitochondrial matrix and produces chemical energy (ATP, NADH, and FADH₂) from oxidation of the pyruvates from glycolysis. In oxidative phosphorylation, the electron transport chain produces chemical energy stored in the NADH and FADH_2. There are 3 ATP produced per NADH and 2 ATP per FADH₂.

 

 

 

Hypothesis:

If glucose or cane sugar is placed in a container with water, yeast, salt, and sugar, it should release more carbon dioxide than  the  control . Also, we expect the potato starch to produce some carbon dioxide but not as much as the glucose or cane sugar but more than the control. Additionally, the honey should produce the least amount of carbon dioxide since it contains less glucose than the plain glucose but produce more than the control.

 

Materials:

·         5 test tubes

·         5 rubber corks with tubes

·         5 syringes

·         2 Styrofoam tube holders

·         water

·         yeast

·         sugar

·         salt

·         potato starch

·         glucose

·         cane sugar

·         honey

·         labels

·         graduated cylinder

 

Procedure:

1.      Put 35 milliliters of water, 1 gram of yeast, 1 gram of sugar, and 0.2 grams of salt in each 5 test tubes

2.      Add 0.2 grams of glucose, potato starch, honey, and cane sugar in different test tubes

3.      Label each tube according to the different starch

4.      Do not add any carbohydrate to the fifth test tube so that it can be the control

5.      Have your lab partner help you shake the tubes thoroughly so that nothing sticks to the bottom

6.      Then very quickly place the corks with the tubes and syringes(placed at 1 milliliter) on each of the test tubes

7.      Then place the tubes into the Styrofoam tube holders

8.      Then check the syringes every minute for 20 minutes and record your data, make sure that the corks are tightly placed on each of the tubes, they may loosen

  

        

 

Results:

Milliliters of Carbon Dioxide vs. Number of Minutes

 

the y-axis is in milliliters

the x-axis is in minutes

 

Add on Starches	1 minute	2 minutes	3 minutes
Potato Starch	1 ml	1ml	1ml
Glucose	1ml	1ml	1 ml
Honey	1ml	1ml	1ml
Cane Sugar	1ml	1ml	1ml
Control	1ml	1ml	1ml
	4 minutes	5 minutes	6 minutes
Potato Starch	1 ml	1ml	1ml
Glucose	1ml	1ml	1 ml
Honey	1ml	1ml	1ml
Cane Sugar	1ml	1ml	1ml
Control	1ml	1ml	1ml
	7 minutes	8 minutes	9 minutes
Potato Starch	1 ml	1ml	1ml
Glucose	1ml	1ml	1 ml
Honey	1.01ml	1.01ml	1.05ml
Cane Sugar	1ml	1ml	1ml
Control	1ml	1ml	1ml
	10 minutes	11 minutes	12 minutes
Potato Starch	1 ml	1ml	1ml
Glucose	1.02 ml	1.02 ml	1.02 ml
Honey	1ml	1ml	1ml
Cane Sugar	1.05 ml	1.05 ml	1.05 ml
Control	1ml	1ml	1ml
	13 minutes	14 minutes	15 minutes
Potato Starch	1 ml	1.20ml	1.90 ml
Glucose	1.02 ml	1.40 ml	1.80 ml
Honey	1ml	1ml	1ml
Cane Sugar	1.05 ml	1.30 ml	2 ml
Control	1ml	1ml	1ml
	16 minutes	17 minutes
Potato Starch	1.60 ml	1.60 ml
Glucose	2 ml	2 ml
Honey	1ml	1ml
Cane Sugar	2 ml	2 ml
Control	1ml	1ml

 

Conclusion:

 

In this lab, we found that glucose and cane sugar had generated the most carbon dioxide which fails to reject our hypothesis and produced 1 milliliter more carbon dioxide than the control (35 milliliters of water, 1 gram of yeast, 1 gram of sugar, and 0.2 grams of salt). Our hypothesis of the potato starch producing less than glucose and cane sugar but more than the control is also true. The potato starch produced 0.6 milliliters more carbon dioxide than the control. Our hypothesis about the honey was partially rejected, it produced less carbon dioxide than the glucose and the cane sugar as we expected, but the honey did not produce more carbon dioxide than the control. The honey and the control did not produce any carbon dioxide, and the glucose and cane sugar produced the most carbon dioxide.              Even though the control and honey also contained sugar it did not produce carbon dioxide. The two constants in this lab are temperature (from placing the tubes in the Styrofoam tube holders) , and the 35 milliliters of water, 1 gram of yeast, 1 gram of sugar, and 0.2 grams of salt in each test tube. Another constant is also the duration of time for cellular respiration to occur and be measured. Two potential sources of error are not adding equal amounts of the different carbohydrates to each of the different test tubes, and not placing the corks properly on each of the test tubes. If the tubes are not placed properly then carbon dioxide can escape and not be measured in the syringe.  Our data is not completely accurate, we did not properly read the syringes throughout the lab so that may have been the cause , also there could have been a leak in a couple of the tubes which might explain why the potato starch 's level of carbon dioxide decreased near the end of the lab and why the honey and control did not produce carbon dioxide.This lab proves that glucose is a major source of energy and produces more energy faster than other carbohydrates.

 

Citations:

Pearson. "Cell Respiration: Overview of Respiration." Cell Respiration: Overview of Respiration. N.p., n.d. Web. 15 Feb. 2014.