We are living in an interesting time with COVID-19. School has switched to e-learning and the kids are home for the rest of the year. If you are like our family there are good moments and then there are the times the kids are going a little stir crazy! Well there are lots of cool science experiments out there that can give the kids some entertainment while still learning.
This experiment is in a video format, however be sure to check out the other "Science for Kids" activities I have blogged on in the past.
As for the experiment we are going to do today, it is a very simple one to do at home. It helps explain and show how water can actually move UP. A really tall tree still needs water to reach all the way to the top. How does this work? Well let's take a look to find out.
I love going out and teaching kids about science. Since moving from North Carolina to Indiana, I have really missed engaging in STEM outreach at local schools. However a group of us at work decided we would be on the lookout for these opportunities and get into some schools. Our company Inari has been supportive of our efforts and so we recently found a local middle school, East Tipp that welcomed us to take over an 8th grade science class for a day.
The group at work has been amazing as we build out our activities and lessons. The credit for this science module that delves into population genetics goes to Cole Davis. He put together a great lesson!
Objective:
The objective of this lesson is to learn more about about population genetics which is the study of gentic variation in populations. Some of the concepts to tackle include gene frequency, dominant, recessive, homozygous, heterozygous, etc. The core exercise involves tasting PTC (phenylthiocarbamide) paper and mapping out the class population genetics based on the whether each student can taste the bitter compound (PTC) or or not taste PTC.
DNA is how all of our genetic identity is stored and thus determines who are are and what we look like. This DNA encodes for GENES and our genes are ultimately translated into many different proteins. Proteins define all the functions in our bodies or in a living organism.
This figure shows how DNA is transcribed to RNA and RNA is translated into protein.
The exercise today looks at one particular protein called a PTC taste receptor that is found in on the tongue. We have lots of taste receptors that allow us to taste salty, sweet, bitter or sour. Each different receptor is coded by our DNA. One of those genes found coded in our DNA is for a PTC taste receptor that allows some of us to taste PTC. If you can taste it tastes very bitter!
For around 75% of the population, PTC tastes very bitter! For the other 25% of the population they do not taste any bitterness (or anything at all) when trying PTC.
The PTC taste receptor protein found on our tongues looks like this:
Whether you taste PTC or not is determined by just one gene called TAS2R38. The genes we get are determined by our parents. For all genes, we all get one copy of a gene from our mom and one copy of a gene from dad. Our parents DNA is ultimately what determines the makeup of our DNA and so our parents can give us different versions of the PTC gene depending on what they have. The gene version that forms a protein that can taste PTC is a DOMINANT gene. If we have just one gene from our parents that is dominant we can taste PTC. However over time, the DNA code changed and that change means the DNA translated into a slightly different protein. This changed version of the gene is RECESSIVE. The new protein that some people have from a recessive version of the gene is not functional, meaning it does not work and the receptor does not taste the PTC. However since you get a copy of the gene from mom and a copy from dad, you need to have both recessive copies (non-functional) in order to not taste PTC.
PTC gene:
A = Dominant (just one copy can taste PTC)
a = Recessive (takes two copies to NOT taste PTC)
Individuals have 2 copies of the genes: One from each parent
AA = "Taster" since both copies are Dominant from each parent = Homozygous Dominant
Aa or aA = "Taster" since one parent still gave a dominant version of the gene - Heterozygous
aa = "Non Taster" since both parents gave a recessive version of the gene = Homozygous Recessive
EXERCISES
Exercise 1: Taste the PTC paper
With the background out of the way, now the fun can begin. The students can take the PTC paper and taste it. At this point you see all kinds faces and get all kinds of reactions!
This just tastes like paper.
YUCK!
I don't taste anything
That was disgusting!
I didn't like that!
As long as you have a decent size population, you will have some tasters and non-tasters. Statically 1 in every 4 people do NOT taste. However, smaller populations can have very different frequencies. Once everyone tastes you can dig into the genetics of the class.
Exercise 2: Class Frequencies
The first thing to do is get the frequencies of the class population. How many tasters in the class? How many non-tasters? After determining the class size you can determine the percentage of tasters (AA, Aa, or aA) vs the non-tasters (aa). Did the class follow the average 75% taster / 25% non taster human population? If not, why would the class frequency look different?
Exercise 3: Hardy-Weinberg Equation
When we look at the class population data, we now know with certainty that the non-tasters are aa or homozygous recessive. However everyone that tasted the PTC could either be AA (homozygous dominant) or Aa / aA heterozygous. There is a mathematical formula that we can use to predict how many people in the class are AA vs heterozygous. The formula is called the Hardy-Weinberg Equation and as a class we worked through solving it. Following steps 1-5 below will solve this equation.
Exercise 4: Random Distribution vs Hardy-Weinberg Equation
We just predicted the percentage of AA, heterozyous and aa frequencies in our class using the Hardy-Weinberg equation. Now we tried to simulate natural variation in the population by rolling a dice so that each Taster could assign themselves as AA, Aa or aA. The non tasters are still aa.
Each taster rolls a dice and based on there rolls they are the following.
1 or 2: aA
3 or 4: Aa
5 or 6: AA
Since each student now has a genetic identity for PTC based on the dice roll if they were tasters, we re-calculated the frequencies and compared it to the Hardy-Weinberg result. If there were differences we discussed the reason. The results was usually much closer when we had a really big class. In the smaller classes the two results were usually a little different.
Exercise 5: Bottlenecks
After working through the population genetics we talked some about bottle necking. This is when a population is reduced to a smaller group or size and the limited diversity in the that population becomes the new norm.
I work in agriculture and there has been intentional bottlenecking through artificial selection in some crops. We talked a little through this concept. This bottlenecking is one of the reason we have been able to increase yields.
There are also examples where bottlenecking in agriculture has had consequences. The potato famine is one example we talked through as a class. The lack of genetic diversity led to a loss of the potato crop which in turn led to starvation and death.
The Irish relied on one or two types of potatoes, which meant that there wasn't much genetic variety in the plants (diversity is a factor that usually prevents an entire crop from being destroyed). In 1845 a strain of water mold accidentally arrived from North America and thrived in the unusually cool moist weather that year. It continued to destroy potato crops from 1846 to 1849.
The PTC paper really helps to bring some fun into the concept of genetics. There are some worksheets that Cole put together that allow the students to work through these exercises. The worksheets contain even more details and scenarios depending on how deep you would like to go with this science lesson.
It has been a busy summer, but I finally got back into a classroom to have fun doing science with middle schoolers. It has only been a few weeks since I transitioned from Bayer to my new employer BASF as part of a large divestement. Yet in that small amount of time, it did not take long at all to see that BASF is also a strong agvocate in our community. As a large BASF group we all took half a day to head over to East Wake Middle School in North Carolina to meet a bunch of 8th graders.
Game faces were on as a bunch of enthusiastic folks from BASF wore their green shirts with pride.
Some of have been doing outreach together for a long time so you gotta take advantage of selfie moments.
Once we loaded up it was a short trip to East Wake to meet the students. We split up into groups and headed to our classes where my team ended up meeting Ms. Shores class. What a great opportunity it was to take some time out of our busy day and work with students and to work closely with my BASF colleagues Courtney, Paulette, Casey, and Yasmin. This is an account of my expereince with one class, but there were similar stories going on across many other classroms with other teams.
We first had to safety up. And we would not look like scientists without our lab coat, glasses, and gloves!
The last time I used cabbage juice as a visual indicator of pH I just used some powder extract you can buy on amazon. The organizers of our group went an extra mile and actually made the cabbage juice indicator the night before. So if you want to make you own, here are the instructions. Instructions are courtesy of BASF materials.
After explaining a little about pH we tired all kinds of stuff to see if it was acidic or basic.
Next up we talked about water and they all agreed clean water is super important. We showed that water can have different types of contaminants. Soil, sand, and dirt make water dirty, but so do other contaminants like heavy metals or other chemicals. We had a tube of water with sand and used food coloring to show other contaminants. This dirty water definitely needed cleaning up. First it went through just a regular filter and everyone's hypothesis that the filter would just catch the sand was correct. The water no longer had dirt in it but it was still colored from the food coloring.
First we added the water to just a paper filter.
The next thing we learned was that activated charcoal is a material that can help clean up water. Everyone had their dirty water with dirt and food coloring to try and clean up again. They put it through a paper filter again, but this time it also passed through some activated charcoal that we had added to the top of the filter. I heard a few gasps when the water really did come out clear and clean as oppsed to dirty and red from the food coloring.
Lastly we just had a chance to talk. Each of us from BASF joined 4-5 students and had about 10 minutes to just talk. Of course the topic of video games did come up and most of them did indeed play Fortnite. Maybe I gained a little more respect when they learned I like to play Fortnite too. But I also heard such ambition and drive from this group. One young lady wanted to be a Youtuber. When I asked how many subscribers she had, she reported it was over 1000!! I told her I barely get 5 likes on my instagram pictures! They are so talented! There were two that wanted to be marine biologists, 2 who wanted be a doctor, a couple that wanted to soccer players, one that wanted to be a lawyer, and other aspirations And of course some who did not know which is OK too. I did not even know what I was going to be and more importantly really like until I got my second job after college.
Whatg a great day. Thanks to the teachers, to the school, and to BASF for organizing this day. I encourage all of you to pour your knowledge and passion on a subject into this generation whenever you get the chance. They listen, they question and they fill you with hope for our future.
Have you ever had heartburn and gone to the medicine cabinet to grab some relief. Then have you ever stopped and wondered how that medicine is actually working? Heartburn is caused when acid from the stomach moves up in the esophagus. The sphincter muscle controls the opening from the esophagus to the stomach so if this muscle does seal correctly you can feel heartburn. The stomach is covered in thick mucous and is protected from the acid, but the esophagus does not have that protection.
One way antacid can work is by reducing the acidity of the acid in your stomach. If the acid is not as strong it will not inflame the esophagus as much. However the antacid Gaviscon works a completely different way and the chemistry is pretty ingenious.
Sodium Alginate is a polymer that is derived from seaweed. Once it goes into the stomach, the acid in our stomach makes it go from a soluble state to an insoluble state. In other words it becomes a solid. Secondly there will be Calcium ions in the stomach from the calcium carbonate. The calcium helps to cross-link the alginate molecules together into something called an "alginate raft." You are left with a big piece of solid material in your stomach from the medicine.
The second piece of the story is the calcium carbonate and sodium bicarbonate react with the acid in your stomach to form carbon dioxide gas. The gas that is formed propels the solid alginate raft upwards. It gets caught at the top of the stomach where the esophagus and stomach come together and forms a barrier. This barrier prevents acid from going up into the esophagus.
This is an amazing piece of chemistry and all of it relies on the acid in our stomach to start the reactions. The neat part is we can replicate the experiment.
Supplies needed:
250 ml flask: This replicates your stomach. The bottom portion is your stomach and the neck of the flask is your esophagus.
50 mL Gaviscon liquid
150 mL of 1M Hydrochloric Acid - This can be pretty nasty and most will not have access to this. So be very careful if you do. (safety glasses, coat, eye protection)
The Experiment
This experiment is quite simple.
1. Add 150 mL of 1M HCl into the flask
2. Add 50 mL of Gaviscon to the flask
3. Observe
Watch the Gaviscon go from a liquid to a solid while the alginate raft forms. Observe Carbon dioxide bubbles forming. And finally watch the gas push the raft up to the neck of the flask and form a barrier.
The barrier actually makes it difficult to get the HCl out of the flask when we cleaned up!!
You just saw a real life application of chemistry in a over the counter medicine thousands of people use everyday. And it was so fun seeing the students doing the experiment.
Maybe you are a teacher and had a long week with the kids struggling on a subject. Maybe you a scout leader and the kids were rowdy and unfocused this week. Maybe you have a passion for outreach of some kind, but after one interactive night you never see those kids you talked to again.
If you are like me, then the question pops up am I really making a difference? Is this time worth it? I know that deep down in our hearts we all know it is worth it and it really does make a difference. However the scientist in me asks for the evidence. I wanted to find a personal story that speaks to the time and passion that our teachers, advocates and mentors spend investing into our younger generation.
In fact when I was at the 4H Youth Summit a few weeks ago, I walked right into one of these stories. I met a wonderful group of students from Wake County, NC who our group with our Bayer shirts. They immediately came up and introduced themselves and told us their story. After hearing it, I asked them if they would write their story so I could share it. Their story is a testament to the importance of outreach by all of us. It is a perfect example of why the investment into our kids is worth every second.
Here is the story about how outreach inspired Humairaa, Ameen, Duha, and Anam to not only dig deeper and learn more about a subject, but start their own outreach activities.
SO SMALL, YET SO MIGHTY
First
and foremost, we would like to thank Bayer for giving us an opportunity to
write about our journey on our enthusiasm in bees. Second, we would like to
thank our mentors, Elizabeth Driscoll and Sarah Dinger, for sparking our
interest in pollinators. We are a part of 4-H Wildweeds, located in Wake
County, and Project Plants, a middle school horticultural science club
exploring everything from soil and water to plants and pollinators. Project
Plants is a partnership between the J.C. Raulston Arboretum, NC State
University, and North Carolina 4-H. Humairaa and Ameen Zafirudin graduated
during the first year of Project Plants 2014 -2015 while Duha Iqbal and Anam
Akhtar graduated in 2015- 2016.
During
our time at Project Plants, we visited Bayer Bee Care Center located in
Research Triangle Park, North Carolina. We explored the facility and were
fascinated by the numerous jobs performed by pollinators, specifically bees. We
learned about the importance of bees and how they aid in the production of many
agricultural products. We became fascinated by bees after our visit.
Generously, Bayer Bee Care granted us with funding to start our own
youth-managed beehive in the JC Raulston Arboretum. Over the summer of 2016,
Elizabeth Driscoll and Sarah Dinger invited us back to start the construction
of our beehive. We all worked together to design and compile the pieces of the
beehive. After hours of hard work, we completed the structure of the bee frames
for the beehive. Later that year, our beehive thrived with many healthy and
lively bees! We would observe the way they went from one flower to another
collecting pollen. We learned many thought-provoking facts about bees, and
wanted to share them with the rest of our community.
We
were all thrilled when we heard about the 4-H National Youth Summit so we
decided to submit a proposal to the National Youth Summit on the topic, “Bee
Good Stewards.” Pollinators play a significant role in each of our lives and
the topic is engaging to all ages. We were eager to present our topic to our
peers. We sought a hands on presentation, so we decided to put together
activities that wouldspark interest for people of all ages.
Our
very first activity in Project Plants was pinning bees. Bee pinning is
essentially taking frozen bees and pinning their body parts on a piece of wood
or styrofoam. There are many benefits associated with bee pinning. It is an
excellent way to preserve bees, so we can further utilize them for research.
Additionally, we can examine the different, detailed parts of the bee,
classify their species, distinguish between their genders, and learn about
their behaviors.
Bees
secrete beeswax from special glands on their abdomen. Beeswax is incorporated
in many items such as candles, lotions, sunscreens, chapstick, and many more.
We decided a fun way to engage youth and adults would be by making chapstick.
We bought beeswax pellets, essential oils, shea butter, and coconut oil to
produce our chapstick. We melted all the materials in a pot and put it in a
chapstick molds. Everyone enjoyed taking part in the production of organic and
natural chapstick. They even got to take theirs home!
Undoubtedly,
bees help us in many ways. Bees greatly impact our lives by pollinating
most of our fruits and vegetables. Therefore, we collectively came up with the
idea to make smoothies. While using the fruits pollinated by bees for our third
station. We used fresh strawberries, raspberries, blackberries and blueberries.
We also used bananas but when we furthered our research we figured out bananas
are pollinated by other organisms. Despite that, we mixed all our fruits
with honey to make smoothies and we each got to try some.
Our
final station was called “Habitat Haven” where youth created landscape designs
of pollinator gardens. This station required participants to use their
creativity and imagination. Participants all came up with fascinating ideas and
enjoyed designing various arrangements.
Our
trip to the 4-H National Youth Summit was one of the best experiences we have
ever had. We enjoyed sharing our knowledge about pollinators with others and
providing fun-filled and educational activities to go along with that. When we
first learned about pollinators, we were amazed to learn of the multitude of
tasks performed by them. That is why we decided to dig deeper into this topic;
we wanted to show everyone our appreciation for bees and all their vigorous
work. Before Project Plants or our visit to Bayer Bee Care, none of us really
thought about how greatly pollinators impact our daily lives. Pollinators are
crucial to the existence of plants, animals, and us! So next time you go
outside and come across a honeybee, do not run away out of fear; instead, take
the time to admire how such a magnificent, yet tiny organism is critical to
your life.
WOW. These 4 walked into the Bayer bee care center and then found some amazing mentors at a local university where they learned and connected with a topic. If not for those meetings, they may not be doing what they are now. There are defining paths we take in our life at certain moments. Most of the decisions we take for one path fork or another is influenced by those around us and this is why it is so important to give our time for outreach. I now know that Humairaa, Ameen, Duha, and Anam are going to mentor others and inspire even more leaders as they place themselves in other's life paths. Stories like this inspire me and give me so much hope. For all the teachers, agvocates, and mentors out there, keep making a difference!
Here were some other pictures of their outreach. What an amazing group!
There was a flyer laying on the table at work advertising the fact that Bayer and the 4H were teaming up. My first experience with that team-up was an awesome.. On a weekend in January I got to go with some of my colleagues to participate in the 4H National Youth Summit Series on Agri-Science in Chevy Chase, Maryland. This is just a few miles outside of DC although I quickly found out a mile in DC takes a lot longer to travel than in my town. I thought I would share my experiences including some great time in the city itself.
The teamup with Bayer meant I got to know a little more about the 4H.
The first question I had is what do the H's in 4H stand for: They stand for head, heart, hands, and health. I even learned the 4H motto which is "TO MAKE THE BEST BETTER." Here is a little more about 4H taken from their website, https://4-h.org/
It's headquarters is located in Chevy Chase, Maryland and that was our first stop to get checked in for the weekend.
DAY 1
It was time to drop in to center.
The site was bought by the 4H in 1959 where it had been a women's college. It now houses meeting rooms, dorm style hotel rooms, and a cafeteria for many 4H events like ours and can house over 800 people.
We had the rest of the day to explore before the keynote speaker that night. We had done a little pre-planning and scored a tour of the White House. If you haven't toured the White House, I highly encourage you to do so. It takes a little up front work, but it is worth it!
Here are just a few of the sites you would see in the white house
Then it was off to the Holocaust Museum and Arlington Cemetery, with a pass by the Washington Monument. These are some tough places to visit, but a powerful story awaits.
Back to the 4H center the first speaker was Stephen Censky, the US Deputy Secretary of Agriculture. He gave a positive message to all the kids about agriculture and their future in the Ag industry. Couple of the things he mentioned were:
“if you want a challenging career, pick #agriscience bc in next 32 years we have to produce as much food as last 10,000 years.”
“Do right and feed everyone.”
DAY 2
The day started off with a career fair. There were people from multiple jobs in agriculture including, Bayer, the US Park Service, and many others.
The was followed by a speaker from the University of the District of Columbia. I learned that this university located in DC is actually a land-grant university that caters to urban farming. If your ever in the area check this place out which houses a large farm on the rooftop.
After these events we all took a field trip down to DC. During the day we went the Smithsonian, the Botanical Gardens, and a walk past the capitol building. Some beautiful sights as well as so much knowledge to take in at these amazing museums.
During the night we took a tour of five DC monuments at night. The stops included the World War II Memorial, the Vietnam Veterans Memorial, The Lincoln Memorial, the Korean War Memorial, and the MLK Memorial. They are beautiful in the day, but the night let's you see them in another perspective.
Speaking the MLK monument, this is one of my favorite quotes:
DAY 3
The last full day of the youth summit involved multiple workshops all through day. I attended a couple and then helped run some others.
The first one I attended was "Precision Farming - Yesterday, Today, Tomorrow, and You." This was presented by Luke Zerby from New Holland. I can tell you that when it comes to technology agriculture is leading the charge. Your phone has a GPS accuracy of 16.4 Feet. That tractor going through the field with a GPS system has an accuracy of 6-9 inches. This is how ag is evolving and I can't wait to see how it plays out.
The second workshop that I went to was "The Growing World of Ag Technology" presented by the Nebraska Extension in Washington County. The extension educator is Tracy Behnken and she presented this workshop as a train the trainer. They have some awesome ideas to help show anyone from primary school on up to high school the importance of agriculture and the facts that support the need for continued innovation in the field. The posters they used can be replicated and for more information the Extension Center has info.
Here is what the program looks like and the extension center would be happy to help get you started.
The second activity from this workshop was how to make butter. This was a great way to help introduce to groups where our food comes from and is a fun, easy, and hands-on exercise.
I enjoyed myself!
Next the University of Maryland showed off a complete curriculum to help teach STEM to middle schoolers. Check this free resource out and use it!
Alright, now it was time to roll up our sleeves and help run some workshops.
The first workshop is one I have talked about before. The exercise lets students come pick a GMO or gene edited product concept and market it from start to finish. Product concept 1 was a product that gave pest control and product concept 2 gave a yield increase. They make many decisions along the way like whether to research internally or use a 3rd party and how many field trials they would run. Finally they would come up with their own product name and see how much profit they make based on the decisions they made.
We ran two sessions with 4 groups at each session and here are the 2 sets of product names.
The next 2 sessions we ran were some general hands-on and information on GMOs, traditional breeding and gene editing. First DNA extraction from strawberries ensued with Kurt showing where the DNA in a plant cell is located and how we were going to break it out..
Next we watched a video on trait research which i have shared before. But if you haven't seen it, it is a great one to watch.
And then Kurt had some fun showing the kids how GMOs, traditional breeding, and gene editing differ and why we need all these tools. Kurt even showed off his passion for GMOs !
For added effect Kurt had gotten some GMO Arctic Apples that are a product that does not brown like a traditional apple. The pictures speak for themselves. Both of these apples were cut in half at the same time.
