Life Science & Biology Projects

Question: What is The Structure of DNA?

To initially see how DNA is organized, form a model of it. This is a streamlined model of DNA, however, now it will give you the general image of how the sugars, phosphate groups, and bases all interface together to make the well known double helix state of DNA. You can make a DNA model out of an assortment of materials. In this experiment we will be using gummy bears to build a DNA model.

DNA

Materials Needed:

Mini marshmallows

Red and black hollow licorice sticks

Toothpicks

String

Gummy bears

Procedure:

  1. Cut the red and black licorice sticks into one inch strips.
  2. Make two equivalent lengths of licorice strands by threading the bits of licorice onto the string, exchanging the red and black pieces.
  3. Assemble four unique shades of gummy bears, marshmallows, and toothpicks.
  4. Combine two shades of the gummy bears together and after that match two different colors together. For instance, red and orange gummy sets could be matched together, green and yellow ones could be combined together.
  5. Take a gummy bear and string it onto the toothpick. String the marshmallow onto the toothpick with the goal that it is in the focal point of the toothpick and alongside the gummy bear. String the reciprocal gummy bear onto the toothpick with the goal that it is by the marshmallow. You ought to now have a toothpick with a gummy bear marshmallow gummy bear focused on it.
  6. Repeat step five to make more gummy bear marshmallow toothpicks, ensuring the gummy bears are coordinated with their correlative hues. Make the same number of these toothpicks as you have red pieces on one of your licorice strands.
  7. Take one strand of licorice and begin appending the gummy bear marshmallow toothpicks to it, interfacing one of these toothpicks at each of the red pieces on the strand. At that point, take the second licorice strand and interface it to the opposite side of the toothpicks. Once more, associate the toothpicks to the red bits of licorice. You should wind up with a ladder with the red and black licorice stands making the sides of the ladder and the gummy bear marshmallow toothpicks making the rungs of the ladder.
  8. Hold the candy ladder up and turn the top counterclockwise to add the twists to the ladder.

Result:

You have just made a candy model of a strand of DNA. The red licorice represents the sugar deoxyribose, the black licorice represents the phosphate groups, together they both represent the sugar-phosphate backbone of DNA.

The gummy bears represent the bases that make the code of DNA. The four unique colors are utilized to represent the four distinct bases found in DNA: adenine (A), thymine (T), guanine (G), and cytosine (C). It doesn't generally make a difference in your model the amount of a base you utilize or where it is put in the strand, yet it is imperative that bases are matched up accurately: A with T and G with C. In genuine DNA, the order does make a difference as that decides what kind of life form it is and how it will behave.

The marshmallow in the middle of the gummy bears represents the hydrogen bonds connecting the bases. This is the time when the DNA strands begin to come apart as they replicate and where the new strand associates with the first strand. Twisting the ladder at the top in a counterclockwise heading gives the DNA model its actual shape; a right-handed double helix.

Question: Which Disinfectant Works the Best?

When you wash your hands you are trying to remove any germs that may be on them from touching things around you. The same concept applies when you wash dishes, wipe a counter or mop a floor. For most of the above activities we use a soap or other disinfecting solution to aid in removing the germs. In this experiment we are going to test a few common disinfectants found around your house to see which removes germs the best.

 

Materials Needed:

Forceps

Cotton Balls from an unopened package

Rubbing Alcohol

Nutrient Agar Kit

Q-Tips from an unopened package

Disposable Gloves

Large plastic Cutting Board

Permanent Marker

Slice of lunch meat (Ham, turkey, bologna, etc.)

7 Small cups for holding disinfectant solutions

5 different disinfectant solutions (antibacterial soap, diluted bleach, rubbing alcohol, Lysol, Pine-Sol, etc.)

Cookie sheet

Paper towels

Clear tape

Lab Notebook

 

Procedure:

1. Using the permanent marker, divide the cutting board into six sections, numbering each section #1-6 like this:

 

2. Put your gloves on and wipe the piece of lunch meat evenly all over the entire cutting board. Wipe as evenly as you can and then leave it out overnight.

3. The next day you will clean each section of the cutting board with a different disinfectant and test the results by growing the bacteria with you Nutrient Agar Kit

4. Prepare your disinfectant solutions by numbering six small cups #1-6 using your permanent marker. Each numbered cup will match one section of your cutting board.

5. Fill each cup with a different disinfectant and make sure you write down which cup number corresponds to which disinfectant solution. Fill the first cup with water as a negative control solution.

6. In your lab notebook, make a data table like the one below to record your results in.

Number Type of Disinfectant Number of Colonies Other Observations
1 Water (control)
2
3
4
5

 

7. Using the forceps, grab a cotton ball from the unopened package. Dip it into one of the solutions and rub it on the surface of the cutting board with the corresponding number to the cup of solution you dipped the cotton ball in.

8. After each application, throw the cotton ball away and dip the forceps into an extra cup filled with rubbing alcohol to sterilize the forceps.

9. Repeat steps 7 and 8 until you have applied a different disinfectant to to each square of the cutting board. Allow the board to dry completely.

10. After all sections of the cutting board are dry, you are ready to use your Nutrient Agar Kit to grow bacteria. Prepare the agar plates by numbering them 1-6 to correspond to the sections of the cutting board.

11. Use the forceps to grab a clean Q-Tip from the unopened package and swipe one end across one section of the cutting board using a circular motion. Be sure the end of the Q-Tip does not touch anything else.

12. Using your free hand, open the lid of the agar plate that corresponds to the section of cutting board you swiped with the Q-Tip. Run the end of the Q-Tip across the agar plate in a zig-zag motion. Immediately replace the lid of the agar plate and use some tape to secure it. Make sure during this process you don't set the lid down and get it contaminated before placing it back on the agar plate.

13. Repeat steps 11 and 12 until you have swabbed each section of the cutting board and applied it to an agar plate.

14. Leave the agar plates on a cookie sheet in a warm place for 1-2 days, until you can visually see bacteria colonies.

15. Count the number of colonies on each agar plate and write down the number in your data table in your lab notebook.

16. Take a picture of each plate so you can have an actual picture to show the colonies on each plate.

17. Graph your results and compare the different disinfectants. Which worked best? Which performed the poorest?

Posted by Isaac Fornari on 15 February, 2017 Read more →

Question: Can You Breed Bacteria?

Bacteria are a fascinating type of microorganism that play a large role in our lives whether we like it or not. Try growing your own sample of bacteria while monitoring how it reproduces in a short space of time. Compare your original sample with others and get proof that bacteria truly are everywhere!

What You'll Need:

  • Petri Dish of Agar
  • Cotton Swab
  • Procedure:

    1. Prepare your petri dish of agar.

    2. Using your cotton swab, swab a certain area of your house (i.e. collect a sample by rubbing the cotton swab on a surface of your choice).

    3. Rub the swab over the agar with a few gentle strokes before putting the lid back on and sealing the petri dish.

    4.Allow the dish to sit in a warm area for 2 or 3 days.

    5. Check the growth of the bacteria each day by making an observational drawing and describing the changes.

    6. Try repeating the process with a new petrie dish and swab from under your finger nails or between your toes.

    7. Dispose of the bacteria by wrapping up the petrie dish in old newspaper and placing in the rubbish (don't open the lid).

    Posted by Isaac Fornari on 22 December, 2016 biology science projects, elementary, life science projects, middle school | Read more →

    Question: What Is the Safest Way to Thaw Frozen Meat?

    Summary: Often when you buy meat products at the grocery store you freeze them to make them last until they are ready for use. But they come out of the freezer frozen solid, and must be thawed before use. In this experiment we will compare 3 different thawing techniques, and see which results in the least bacteria in the meat once it is thawed.

    Materials Needed: 

    Pack of 5 Petri Dishes

    Nutrient Agar

    Disinfected Swabs

    Bottle of Purified Water

    Clean Chopping Board

    Clean Knife

    Refrigerator

    Chicken Breast Bought Cold from Supermarket

    3 250 Ml Beakers

    Permanent Marker

    Project Procedure:

    1. Prepare 3 Petri dishes using agar and store them in a refrigerator. The Petri dishes are brought to room temperature before the start of experiment by taking them out of the refrigerator, label the Petri dishes as  “Room temperature”, “Fridge” and “Microwave”.

    2. Using a knife and a chopping board, cut out 3 equal cubes of  chicken meat. Keep the chicken cubes inside the freezer for a day.

    3. The next day, the 3 pieces of frozen chicken cubes are removed from the freezer. Remove the 3 cubes of frozen chicken from the freezer the next day. Keep the  1st cube of chicken in  the fridge for the next 12 hours to thaw . Leave The 2nd piece of chicken at the kitchen counter for the next 4 hours to thaw at room temperature. Use the microwave to thaw the 3rd piece of chicken.

    4. Label the 3 beakers as “Room Temperature ”, “Fridge” and “Microwave”. Pour 100 ml of disinfected water into each beaker and soak the thawed meat in it, according to the labels on the beaker for ten minutes. Wash the swab with sterilized water and dip it into the beaker. Swipe the swab at the center of the agar surface according to the label on the beaker and Petri dish

    5. Cover the Petri dishes and keep them in a cool, shaded place for the bacteria to grow, for the next 5 days.

    6. Measure the diameter of the bacteria colony growth after 5 days and record it in the table provided below.

     Thawing method Outside Fridge Microwave
    Bacteria growth (mm)

     

    Posted by Isaac Fornari on 02 March, 2016 biology science projects, middle school | Read more →

    Question: Does Tea Stain your Teeth?

    Summary: Teeth are used for chewing and breaking down food in the mouth to help speed up the digestion process. Teeth are naturally white in color, but over time dark colored drinks like tea, coffee, and cola can stain teeth turning them yellow in color. In this experiment you will use egg shells to simulate the white color of teeth, and study how different liquids effect the color of the eggshells

    .

    Materials Needed:

    Eggs (Hollowed out) use these instructions

    Tea

    Coffee

    Cola

    Three Plastic Beakers

    Project Procedure:

    1. Fill three separate beakers with coffee, tea, and cola.
    2. Put at least one hollowed-out eggshell into each container.
    3. Every day, fish them out and observe the progress of discoloration.
    4. Take some photos of gradual changes. On the day when you really start to notice discoloration, note that day.
    5. Record your results and compare the effects of the three liquids using a table like the one below.

     

      Day #1 Day #2 Day #3
    Tea
    Coffee
    Cola
    Posted by Isaac Fornari on 08 December, 2015 elementary, life science projects | Read more →

    Question: What is the Bacterial Content of Milk?

    Summary: For this experiment we will use Methylene blue to study the presence of aerobic bacteria in milk. Methylene blue is a blue dye that reacts to the lack of dissolved oxygen by turning translucent if there is no dissolved oxygen in a sample. Methylene blue is a good indicator for the presence of aerobic bacteria in a sample because aerobic bacteria use up oxygen.

    Looking for a kit with everything you need to complete this experiment? Click Here!

    Materials Needed:

    Access to a stove and big pot for sterilizing equipment

    5 Test Tubes

    5 Test Tube Stoppers

    Test tube rack

    Paper towels

    Calibrated pipette

    50 ml graduated beaker

    Pot and stove to use as a water bath

    Refrigerated pasteurized milk

     Thermometer

     Kitchen tongs

     Methylene blue

    Project Procedure:

    1. Before starting, make sure you have sufficient temperature control with your stove. Fill a pot half-full with tepid water. Put it on the stove and raise the temperature to 98 degrees. Make sure you can keep it at this temperature for several hours.

    2. Wash your hands. Cover the surfaces adjacent to your kitchen stove with paper towels. Place the test tube racks close to the stove on the paper towels.

    3. Fill the pot with water and bring to a boil. Uncap your test tubes. Using your kitchen tongs, carefully drop your graduated beaker, test tubes and their caps in boiling water. Boil for one minute.

    4. Remove your test tubes and graduated beaker from the water. Place the test tubes in the test tube rack.

    5. Measure 9 ml of milk in the graduated beaker. Measure 9 ml milk into each test tube.

    6. Using your measuring pipette, measure 1 ml methylene blue. Place the methylene blue in one of the test tubes

    7. Using the kitchen tongs remove the test tube caps from the pot, and cap the test tubes. The test tube with the methylene blue is your test sample. The test tube without the methylene blue is your control. Label each test tube.

    8. Pick up your test tube and gently shake it so that the methylene blue is dissolved.

    9. Place each test tube in the water bath.

    10. Examine the test tubes every 15 minutes for two hours and every hour afterwards. Record your observations. If it takes more than 8 hours for the milk to turn white again, the quality of the milk is excellent. If it takes 5.5 to 8 hours for the milk to turn white, then there are less than 0.5 million organisms/ml of milk. If it takes 2 to 5.5 hours for the milk to regain color, then there are 0.5 to 4 million organisms/ml of milk. If it takes 20 minutes to 2 hours, then there are 4 to 20 million organisms/ml of milk. If it takes less than 20 minutes, then there are over 20 million organisms/ml.

    .

    Posted by Isaac Fornari on 26 August, 2015 biology science projects, high school, middle school | Read more →

    Question: Are There Protozoa In My Pond—Or Fish Tank?

    Summary: Protozoa are one-celled creatures that live in water or watery tissues. In a culture medium, they will be visible in about 24 hours, with the most variety of protozoa visible after about 3 days.

    Materials Needed:

    Pond Water or Water from a Fish Tank

    1 Egg

    Pipet            

    Microscope, Compound, up to 400x  

    Microscope slides and cover slips    

    Protozoa Calming Solution (Methyl Cellulose)            

    Project Procedure:

    1. Hard boil an egg and grind a pinch (1/4 gram) of the yolk in a bowl with a small amount of water to form a paste. Add the paste to 1 liter of boiled pond or fish tank water and let stand for two days.
    2. Use the pipet to place one or two drops of the water on a microscope slide. Cover with the cover slips.
    3. Place on a microscope stand and examine the slide with your microscope starting at 40x. Most protozoa have little color and are difficult to see in bright light, so turn your microscope diaphragm to the lowest light setting. It will take patience to adjust the lighting and focus the microscope.
    4. Initially you will see very tiny dots moving around on the slide. Some move very rapidly, others more slowly. You can slow them down for observation by adding a drop of methyl cellulose.
    5. Once you find an area of protozoa activity on the slide, turn the magnification up to 100x or even 400x to see them better.
    6. If no animals are visible, try again each following day. Many conditions, such as water hardness, temperature, and water acidity, can affect the growth and development rate of these organisms. Each succeeding day you will typically find more and different varieties of protozoa in your culture. Initially, smaller species will be prevalent. As the days pass larger species will appear. You will also see different algae forms appear. Certain species will be more common from the top of the cup and others from near the bottom. Gradually, food and water conditions will change, affecting the growth and development rates of the different protozoa.
    Posted by Isaac Fornari on 24 July, 2015 high school, middle school | Read more →

    Question: What is the Difference between Green Plants and Fungi?

    Summary: Some kinds of vegetation contain sugars and some contain starches. The chemical indicator Benedict’s Solution identifies sugars, and iodine identifies starches. Learn how the presence of sugars and starches are different in green plants and in fungi.

    Materials Needed:

    Mushrooms from the grocery store

    Iodine  

    Sugar

    Graduated Cylinder   

    2-cup Clear Glass Measuring Cup

    Benedict’s Solution

    Paring Knife

    Kitchen Stove

    Small Saucepan

    Green Leaves from a Tree or Bush

    Scissors

    Pen and Paper for Taking Notes

    Project Procedure:

    1. Slice a mushroom lengthwise. Using the eyedropper, place 8 – 10 drops of iodine on the interior surface of the sliced mushroom. Write down your observations about color changes.
    2. Dice 4 or 5 small mushrooms into very small pieces. Put the diced mushrooms into a small saucepan with ¾ cup of water and 20 ml. of Benedict’s Solution. Bring the mushroom mixture to a boil and lower the heat to simmer for 5 minutes. Remove from heat and pour into a clear glass measuring cup. Record your observations about the color change.
    3. Repeat the procedure in #2, using 8 – 10 green leaves instead of the mushrooms. Collect the leaves from a tree or bush and use them immediately. Using scissors, cut them into small pieces before covering them with the water and Benedict’s Solution. Continue by simmering the leaves as in #2, removing them from the heat, pouring them into a measuring cup, and recording your observations.
    Posted by Isaac Fornari on 24 July, 2015 elementary, middle school | Read more →

    Stay in touch

    Contact Us

    We'd love to hear from you. Call 800-282-3248 toll-free or 408-727-7301. Email us here. Or come by our retail store at:
    The Science Shop USA
    1043 Di Giulio Ave
    Santa Clara, CA 95050-2805
    Open Mon-Fri. 9 AM - 5:30 PM

    Latest Additions to Our Science Project Database

    • Question: What Are the Best Liquid Conductors of Energy?

      Summary: This experiment explores the kinds of liquids that are the best conductors of energy when splitting the molecules of water through electrolysis. Materials Needed: 9 v Battery Small Electrolysis Apparatus   Distilled Water Baking Soda Lemon Juice Table Salt Dishwashing... Read more →

    • Question: Can You Make a Battery Out of a Potato?

      Summary: In this experiment, a potato is used to create an electrochemical battery, in which chemical energy is converted to electrical energy through spontaneous electron transfer. The energy created is enough to power a digital clock. Materials Needed: 2 Medium... Read more →