Would You Want To Know?

IF you were to have a disease in the future, would you want to know about it? If there was a way to find out that in 30 years, you will suffer from Alzheimers big time, would you want to know??

Genetic testing and disease: Would you want to know?
In the above article, a story is told about a girl who is on her way to have her genes tested to see if she has inherited the Huntington's gene that her parents have, or if she is at risk of developing it in the future. Huntington's is a pretty nasty disease that makes people lose coordination and get jerky movements and lose control. They can become depressed and psychotic. This all leads to the end, where they develop dementia and have to have complete and total care.

Let's ask this again. If you had a disease like the one presented above...would you want to know?

The Human Genome Project is the organization which research on people's genes goes on in order to figure out whether or not they will have these diseases in the future. Since 2003, this organization has identified over 20,000 genes out there.

But here's something to consider...
Gene testing could become a requirement for everyone in the future. This is so that people can know what to prepare for and expect in the future.

Personally, I don't think I would want to know what the future holds for me. I would imagine that the Human Genome Project costs a lot, so I wouldn't like to put forth all the money that could help with future diseases into FINDING OUT about them. I think that knowing what is to come would give me the chance to figure out what happens in the disease(s) that I would develop and I may fall into a depressed state. I'll let it surprise me later!

DNA Extraction from Wheat Germ

Instructions:

1. Place 1 gram of raw wheat germ in 50 ml test tub.

2. Add 20 ml of hot (50-60 C) tap water and mix constantly for 3 minutes.

3. Add 1 ml or a scant 1/4 teaspoon of detergent and mix gently every minut for 5 minutes. Try not to create foam.

4. Use an eyedropper, pipette, or piece of paper towel to remove any foam from the top of the solution.

5. Tilt the test tube at an angle. SLOWLY pour 14 ml of alcohol down the side so that it forms a layer on top of the water/wheat germ/detergent solution. Do not mix the two layers together. DNA precipitates at the water-alcohol interface (the boundary between the water and the alcohol). Therefore, it is crucial to pour the alcohol very slowly so that it forms a layer on top of the water solution. If the alcohol mixes with the water, it will become too dilute and the DNA will no precipitate.

6. Let the test tube sit for a few minutes. White, stringly, filmy DNA will begin to appear where the water and alcohol meet. You will usually see DNA precipitating from the solution at the water-alcohol interface as soon as you pour in the alcohol. If you let the preparation sit for 15 minutes or so, the DNA will float to the top of the acohol.
     You can usually get more DNA to precipitate from the solution by using one of the DNA-collecting tools (such as glass or paper clip hook) to gently lift the water solution up into the alcohol. This allows more DNA to come in contact with the alcohol and precipitate. You may find it helpful to pour the water/detergent solution into a clean test tube, leaving behind the wheat germ, before adding the alcohol.

7. Use a glass or paper clip hook or wooden stick to collect the DNA.

OBSERVATIONS

1. What does the "wheat germ soup" look like?
     The "wheat germ soup" looks much like watery snot...interesting....different.

2. How does its appearance change as you add the detergent and swirl it in?
     The "snot look" begins to form. The DNA, or "stringy parts" start to develop.

3. What do you think is happening at this step?
     The DNA is beginning to form.

4. Describe the appearance of the mixture just after you add the alcohol.
     The two solutions are separate, but in the same tube. It looks layered.

5. What do you think is happening at this step?
     The two solutions are separating so that DNA can form in between them. They're working as glues.

6. What do you observe at the water-alcohol interface?
     The wheat germ met the alcohol, so that's where the filmy DNA film started forming.

7. What does DNA look like?
     The DNA looks like snot. Creation of life is beautiful...but really not too pretty!

Investigating Independent Assortment

INVESTIGATING INDEPENDENT ASSORTMENT

Mendel observed the effects of independent assortment when he carried out his dihybrid crosses. When he crossed two plants that bred true for different versions of two traits, the first-generation offspring all displayed the same phenotype (the dominant phenotype for both traits). However, when these plants were crossed, the second-generation offspring included four different phenotypes.

Mendel carefully recorded the numbers of phenotypes among the offspring of many dihybrid crosses. He found that certain combinations of phenotypes among the second-generation offspring occur in a 9:3:3:1 ratio, on the average. We now know that this pattern occurs because genes on pairs of homologous chromosomes are sorted out for distribution into one gamete or another independently of gene pairs of other chromosomes.

Activity

In this activity, you will first access the meiosis tutorial provided by the University of California, Santa Barbara. The tutorial demonstrates the random assortment of chromosomes into gametes. Next you will complete a tutorial quiz about independent assortment. This is part of The Biology Project from the University of Arizona.

Part 1.

Use your browser to go to the meiosis tutorial at

http://www.sumanasinc.com/webcontent/animations/content/independentassortment.html

Use the tutorial to learn how to determine which allele combinations are possible in two or even three trait crosses.

Part 2.

Use your browser to go to the independent assortment tutorial at
http://www.biology.arizona.edu/mendelian_genetics/problem_sets/dihybrid_cross/dihybrid_cross.html
Go through questions 1-9 of the tutorial. If you answer any question incorrectly, review the tutorial material and try again.
When you have completed this much of the tutorial, answer the questions below:
1. What type of gametes will be produced by a plant of genotype AaBb?
cross, the phenotypic ratio is 9:3:4. There are only three different phenotypes 
for hair color, agouti, black and albino. The individual with genotype recessive 
for both traits, i.e. aabb, has the same albino phenotype as the aaBB and aaBb 
individuals due to epistasis.
2. What type of gametes will be produced by a plant of genotype aabb?
might be caused by the recessive homozygous, recessive bb genotype.

Rather than the 9:3:3:1 seqregation of phenotypes normally seen with an AaBb x AaBb dihybrid 

Same as stated above, only the albino phenotype masks any phenotype that 

3. List all the genotypes you would find among the offspring of an AaBb x aabb test cross.Half of the gametes get a dominant S and a dominant Y allele; the other half of the gametes get a recessive s and a recessive y allele.Both parents produce 25% each of SY, Sy, sY, and sy.

4. What is the expected phenotypic ratio of the offspring of an AaBb x aabb test cross?
These phenotypes will appear in a predicted 1:1s:1:1 ratio.

5. List all possible gametes from a trihybrid individual whose genotype is RrSsTt.
If only recessive traits were scored, we would only consider offspring with one
phenotype: dented, green seeds. A 9:3:3:1 ratio phenotypes would be impossible.

Let's Make A Baby!

     For this experiment, my classmates and I were to partner up and make a baby! Not literally-but on paper with the cool, fun techniques of biology! As my class evened out to an ODD number of students that day, we decided that it would only be fair to make my partner the great and glorious Enrique Iglecias!

(Two pretty attractive people, we know!)

So for this project, my partner and I were to look at each others' faces and match up listed features on the page in order to decide upon which features our child will likely have. This helped us determine exactly how our child will look.

A long and tough process, but we were able to define each others' beautiful traits our child would probably be getting.














Following are the final results...

(Adorable!!)

Onion Root Tips Mitosis WebQuest

ONION ROOT TIPS AND THE CELL CYCLE


In this activity, you will calculate the lengths of the various phases of the cell cycle in an onion root tip. First you will view some slides and graphics of onion root tips provided by the Molecular Expressions Photo Gallery. Then you will complete the online activity provided by the Biology Project at the University of Arizona.

Part 1.

Use your browser to go to Molecular Expressions Photo Gallery: Mitosis

http://www.microscopy.fsu.edu/micro/gallery/mitosis/mitosis.html

Notice in the micrograph at the top of the page that there are cells in a variety of stages. View the onion slides in this section, then click on "mitosis" in the sentence "Learn the steps in mitosis ... " This will take you to a Java tutorial.  Keep in mind what you have learned here as you proceed to the second part of the activity.

Part 2.

Use your browser to go to Online Onion Root Tips at

http://www.biology.arizona.edu/cell_bio/activities/cell_cycle/assignment.html
Begin by reading the description of the five major cell phases. You will need to keep this information in mind during the activity.

Make a copy of the data sheet that appears on the second page. You will need it to answer the questions.

Proceed through the activity, identifying the phase for each cell you are shown. Pay attention to the hints if you misidentify a cell at first.

When you have completed the activity, answer the following questions:

1. What percent of cells were in interphase?
20%2. What percent were in mitosis?
100% All of the cells are in different stages of mitosis.3. Which phase of mitosis takes the longest?
Interphase
4. During which stage is the nucleolus visible as a dark spot?
Prophase5. How can you recognize a cell in metaphase?
It doesn't seem as dark as prophase; It's much lighter and looks like it's beginning to separate.6. How might you figure out how long (in minutes and/or seconds) each phase of the cell cycle takes based on the data from these onion root cells? Explain your logic and show your calculations and results below.

7. Produce a pie chart in Create-a-Graph that shows the relative lengths of each stage of the cell cycle in these cells including interphase and each stage of mitosis. You can embed the graph here.

	Interphase	Prophase	Metaphase	Anaphase	Telophase
Number of Cells	20	10	3	2	1	36
Percentage	55.55%	28%	8.33%	5.56%	2.78%	100%

Photosynthesis Dry Lab

Photosynthesis Dry Lab

In this “dry lab” you will be working backwards from what you would normally do in a lab situation. In this case, you will be given a set of observations that were made in a lab and you will be asked to reconstruct the procedure that could have generated this data. You will also be given a set of facts that you will use to explain this set of observations in the analysis and conclusions section of your lab write-up. As you create the procedure for this lab, please remember all the rules that you have been learning about good experimental design.

Your lab report begins below. Fill in the missing sections of the lab report using the observations and facts given. You may assume that you have access to as many test tubes, snails, Elodea plants, light sources, dark places, and as much pond water and BTB as you need.

Make your own copy of this Google Doc and edit the lab report that begins here:

---

My (only) Most Awesomest Photosynthesis Lab Report

by Cynthia Justice

Purpose: Is photosynthesis possible in animals? With different chemicals? Is light necessary?

Background Facts:

• Carbon dioxide in water produces carbonic acid.
• Bromothymol Blue (BTB) is a blue-green liquid which changes to a yellow color in acid and back to blue-green when returned to a neutral pH.
• Carbon dioxide plus water yields sugar and oxygen when chlorophyll and sunlight are present.
• Animals respire.
• Green plants photosynthesize in the light and respire all the time.
• Sugar plus oxygen yields carbon dioxide plus water and energy.

Hypothesis:
If I mix bromothymol with other ingredients in different conditions, the mixture will change colors.
Materials:
4 beakers
bromothymol blue
2 aquarium fish
2 elodea
waterProcedure:
1.  Fill a beaker 3/4 full of water and mix with 40 drops of  bromothymol blue (BTB).  Leave in light for approx. 3 hrs.  Then leave in dark for 3 hours.  Observe!
2.  Fill a beaker 3/4 full of water and mix with 40 drops of BTB.  Put an aquarium fish in with the mixture.  Put in light for 3 hrs.  Put in dark for 3 hrs.  Make observations.
3.  Fill a beaker 3/4 full of water and mix with 40 drops of BTB.  Add an elodea to the mixture.  Leave in light for 3 hrs.  Then in dark for 3 hrs.  Make observations.
4.  Fill a beaker 3/4 full of water and mix with 40 drops of BTB.  Put both an aquarium fish and an elodea in the mixture.  Put in light for 3 hrs.  Put in dark for 3 hrs. Make those final observations!

Observations:

1. Water plus bromothymol blue is blue-green.
2. Water plus bromothymol blue plus an aquarium snail turns yellow.
3. Water plus bromothymol blue plus Elodea (an aquarium plant) is blue-green in light.
4. Water plus bromothymol blue plus a snail plus Elodea is blue-green in light and yellow when left in the dark for three hours.

Analysis and Conclusions:

1. Water plus bromothymol blue is blue-green because...

the water is a neutral pH

2. Water plus bromothymol blue plus an aquarium snail turns yellow because...

the animal respires and produces carbon acid

3. Water plus bromothymol blue plus Elodea (an aquarium plant) is blue-green in light because...

the pH levels of plants stay neutral in the light and photosynthesis process, so the water stays the same color

4. Water plus bromothymol blue plus a snail plus Elodea is blue-green in light and yellow when left in the dark for three hours...

the snail produces carbon dioxide, but there is no light, so the elodea can't go through photosynthesis and the carbon dioxide makes the water acidic, which creates the chemicals reaction and changes the water color in the dark.

Phenylketonuria Web Quest

PHENYLKETONURIA: A METABOLIC DISORDER

Metabolic disorders are genetic diseases that affect the body's ability to perform its normal chemical reactions. Many metabolic disorders result from enzyme defects. Recall that a metabolic pathway is a stepwise sequence of enzyme-mediated reactions. If one enzyme in a metabolic pathway is defective, that enzyme's substrate may accumulate and the pathway may not be completed. This may result in a buildup of harmful substances or a shortage of required molecules.

Activity

In this exercise, you will use the Web links below to gather information about the metabolic disorder phenylketonuria (PKU). Use what you learn to answer the questions at the bottom of the page.

Your Genes, Your Health: Phenylketonuria

http://www.ygyh.org

NSPKU Home Page

http://www.nspku.org

Texas Department of Health Genetic Disorders

http://www.dshs.state.tx.us/newborn

Phenylketonuria - The Genetics

http://willroberts.com/pku/

Questions

1. What enzyme is most commonly defective in people with phenylketonuria?
An enzyme called Phenylalanine Hydroxylase 
2. What reaction does this enzyme catalyze? (What is the substrate and what product is produced?)
PAH. Without this, a person could develop high levels of phenylalanine in the brain, which could poison neurons and cause mental retardation or epilepsy.
3. Describe the symptoms of phenylketonuria.
Smaller than normal head, mental retardation, epilepsy, musty odor, and lighter skin and hair4. What causes the symptoms of PKU, the lack of a substance or the buildup of one?
Phenylalanine reacts badly with PKU because the hindered enzyme is one of a metabolic nature.5. How common is phenylketonuria? How is it treated?

It's not very common at all. It's treated by a low-protein diet that is carried out throughout the patient's life.

Metabolism Intro Notes

Forms of Energy
    Law of thermodynamics
    Metabolic reactions
ATP
Metabolic Pathways
-energy of activation-enzymes
-photosynthesis
-cellular respiration


2 Types of energy:
Kinetic
-energy of motion
-mechanical

Potential
-Stored energy
-chemical


Laws of Thermodynamics
First law:
-law of conservation of energy
-energy cannot be created or destroyed
-energy CAN be changed from one form to another
Second Law:
-Law of Entropy
-when energy is changed from one form to another, there is a loss of usable energy
-waste energy goes to increase disorder

Metabolic Reactions and Energy Transformations
Metabolism:
-sum of cellular chemical reactions in cell
-reactants participate in reaction
-products form as result of reaction
Free energy s the amount of energy available to perform work
-Exergonic Reactions-Products have less free energy than reactants
-Endergonic reactions-Products have more free energy than reactants

ATP and Coupled Reactions
Adensonine Triphosphate (ATP)
-High energy compound used to drive metabolic reactions
-constantly being generated from adenosine diphosphate (ADP)
Composed of:
-adenine and ribose (together=adensosine)
-three phosphate groups
Coupled reactions
-energy released by an exergonic reaction captured in ATP
-that ATP used to drive an endergonic reaction

ATP= ADP + P + Energy



Work-Related Functions of ATP
Primarily to perform cellular work
-Chemical work-Energy needed to synthesize macromolecules
-Transport work-Energy needed to pump substances across plasma membrane
-Mechanical work-Energy needed to contract

Metabolic Pathways
-Products of an earlier reaction become reactants of a later reaction
-Such linked reactions form a metabolic pathway
   -Begins with a particular reactant
   -Proceeds through several intermediates
   -Terminates with a particular end product

Enzymes
-Protein molecules that function as catalysts
-the reactants of an enzymatically accelerated reaction are called substrates
-each enzyme accelerates a specific reaction
-each reaction in a metabolic pathway requires a unique and specific enzyme
-end product will not appear unless ALL enzymes present and functional

Enzymes: Energy of Activation
Reactants often "reluctant" to participate in reaction
-energy must be added to at least one reactant to initiate the reaction
-energy of activation
Enzyme Operation:
-Enzymes operate by lowering the energy of activation
-Accomplished by bringing the substances


Irreversible Inhibition
Materials that irreversibly inhibit an enzyme are known as poisons
Cyanides inhibit enzymes resulting in all ATP production
Penicillin inhibits an enzyme unique to certain bacteria
Heavy metals irreversible bind with many enzymes
Nerve gas irreversibly inhibits enzymes required by nervous system

Cystic Fibrosis Research

CYSTIC FIBROSIS - A DISORDER OF MEMBRANE TRANSPORT

A great variety of proteins have roles in moving molecules and ions across cell membranes. Passive transport proteins permit certain substances to diffuse down concentration gradients by moving through the protein's interior. Active transport proteins use ATP energy to pump substances across the membrane against their concentration gradients. To investigate the importance of transport proteins, we will consider the effects of cystic fibrosis, a genetic disorder in which there is a defect in a transport protein..
Activity

Part 1.

In this part of the activity you will visit the Cystic Fibrosis Foundation’s web site to learn about the causes and symptoms of cystic fibrosis.
Use your browser to go to http://www.cff.org/home/
Use the information provided in the “About cystic fibrosis” section to answer the following questions:


1. What are the signs and symptoms of cystic fibrosis?

very salty-tasting skin;

persistent coughing, at times with phlegm;

frequent lung infections;

wheezing or shortness of breath;

poor growth/weight gain in spite of a good appetite; and

frequent greasy, bulky stools or difficulty in bowel movements.

2. How common is this disorder?

About 1,000 new cases of cystic fibrosis are diagnosed each year.

More than 70% of patients are diagnosed by age two.

More than 45% of the CF patient population is age 18 or older.

The predicted median age of survival for a person with CF is in the late 30s.

3. How is cystic fibrosis diagnosed?
Most people are diagnosed as babies, or before the age of 2 through screening. A sweat test (the more commonly used test) or a genetic test with be performed to determine whether or not it is there.

4. How is cystic fibrosis inherited? Does everyone who has a mutant gene for the protein have cystic fibrosis?

One protein is different for that person. They have inherited two copies of the defective gene. One can have the CF gene, but that does not necessarily mean that they have CF.

Part 2.

In this part of the activity you will read an article to learn more about cystic fibrosis.
Use your browser to go to:
http://resources.schoolscience.co.uk/MRC/3/page3.html
Use the information in this article to answer the following questions:
1. Explain the normal function of the protein that is defective in cystic fibrosis.
This gene will typically show up in the epithelial cells that line the airways of the lungs. There are channels for those cells that allow ions to flow in. This brings the water to the surface and keeps mucus moist. The gene will prevent those from getting moist, leaving them all dried out. This makes it easier for those people to get infections. They need some extra care for that!

2. What happens to this protein in CF patients and what are the consequences for the health of these individuals?
Movement of chloride ions into the mucus are cut off. Sodium ions are allowed to then flow into the cell, allowing it for drying out more. Bad news! That person is then prone to infection.

Part 3.

In this part of the activity you will read about how cystic fibrosis is treated.
Use your browser to go to:
http://www.mayoclinic.com/health/cystic-fibrosis/DS00287
Use the information in the different sections of the article to answer the following questions:
1. Explain at least 3 treatments for the symptoms of cystic fibrosis.
Medications, chest therapy, organ function tests

2. Discuss at least 3 ways for parents to help their children who have cystic fibrosis.

Healthy eating, exercise, and drinking lots of fluid would be great ways to help support and keep their child healthy!