How Much Energy Do Different Foods Contain?

How much energy do these foods contain?

This lab is always a favorite of my students!

I have just finished teaching cellular respiration to my students.  As teachers, we spend so much time talking and teaching about the path of glucose through the reactions of respiration, that I worry that students will come away from a biology class thinking that only glucose can serve as a fuel for respiration.  It is important to help them realize that any organic compound (with modifications) can serve as a fuel for respiration.

This lab is just a basic calorimetry lab.  Students are given three different foods (peanuts, fritos, and marshmallows) and asked to determine the energy content in each.  Students will use this equation to do their calculations:

Energy gained by water = (mass of water) X (Δt of water) X (4.18 J/g°C)

This lab can easily be completed by students who have not yet completed a course in chemistry.

After finding the mass of a food sample, and the initial temperature of water in a calorimeter (coke can), the food is ignited and allowed to completely burn.  The heat lost by the burning food is gained by the water in the can.

Students can determine from their data the amount of energy in each food.  The energy is first calculated in kJ/mol and then converted to cal/mol.

I am fortunate to have the Vernier Probe System at my school.  This makes data collection easy and accurate.  You can still do this lab using a traditional thermometer instead of the probe system.


I am sure that the percent error in this lab is quite high.  However, students get a good idea about the energy content of foods.  Most students predict prior to the lab that the marshmallow will have the most energy.   They mistakingly believe that the higher the sugar content, the higher the energy content of the food.  In this lab, peanuts come through with flying colors with an energy content much, much higher than the other foods.


If interested, here is the lab that I do with my students:  Measuring the Energy in Foods

Help! Biology Vocab is Killing Me!

The most common complaint I receive from my students is, "There are too many words, too many definitions, the words are too hard to spell........"


Sound familiar?  I read once that a first year biology class has more new vocabulary words than the first year of taking a foreign language.  I believe that this must be true.  When I talk to a struggling biology student, they will usually tell me that they understand the concepts and they understand the "how and why" things work as they do, but they just hate to memorize the vocabulary words.  

I try very hard to make my class a "concept" class.  I want my students to have a global understanding of how all the parts of biology fit together.  I want them to have the big picture and to be able to relate one process to another.  I want them to be problem solvers and critical thinkers.  But I am a bit old school!!  I still think the students need to have a mastery of the vocabulary that accompanies the concepts.  I think kids need to be able to spell the important and key terms.  (Don't even get me started on spelling...it is becoming  a lost art!!  And why do kids think that it is okay to misspell words??  ARG!)

I thought I would make a list of the strategies and methods I use to help students memorize vocabulary words.  I hope it will give you some ideas that you can use with your students.  And then I would like to hear from you!  I need some new ideas, too!  If you have a strategy that works, please let me hear from you.

Things I do to teach biology vocabulary:

1. My favorite is the old stand-by....the crossword puzzle.  I make a crossword puzzle for every chapter I teach.  Believe it or not, my students actually like these.  Sometimes I assign them for homework, but more often I use them to award some extra credit points on my unit tests.  I give the puzzle out a few days before the test.  If it is completed by test day....accurately....then I give some extra points on the test.  I think this is great reinforcement of associating the term with the correct definition, AND it is also good spelling practice.
2. Teach the biological prefixes and suffixes!  I spend a good bit of time of the beginning of the school year on this.  If the student knows a basic set of prefixes and suffixes, it will help them all year long.  Examples include:  hetero, home, endo, exo, meso, trans, cyto, lysis, etc.
3. Vocabulary Word Scrambles:  I write fill in the blank type questions.  The correct answer is given with the question, but the answer is scrambled.  The student has to unscramble the word to determine the answer.
4. Flash cards:  An oldie but goodie!  I sometimes give extra credit if the student makes a set of flash cards to go with a particular chapter.
5. Powerpoint Jeopardy Review Games:  This is a favorite of my students.  These are a bit time consuming to make, though.  My students really enjoy the game format.  I also post these on my school web site so that the students can access them from home.

I would love to hear your ideas.  Have you got a neat trick that would help the rest of us out?  If so, be sure to leave a comment.  I can always use a new idea!

Don't Forget the Fungi!

My favorite biology joke:  What did the pepperoni say to the mushroom on the pizza?


Answer:  You're a Fun-Guy!  

My unit on the fungi is one of my favorite units to teach.  Most of the students in my biology class have never had any instruction about the Kingdom Fungi before they reach my class.  They are amazed to learn that outside of the animal kingdom, the fungi are our closest relatives!  The fungi have some amazing characteristics!  We depend on them as decomposers.  Life might cease to exist on Earth if it were not for the fungi breaking down and decomposing dead organisms and returning the chemical elements they possess to the ecosystem to be used in new organisms.

Click picture.

Simply put, there is more to the fungi than just that green mold that invades our pantries and refrigerators!  I have just posted my new "Fungi PowerPoint with Notes for Teacher and Student" to my TpT store.  This product is a 56 slide PowerPoint on the Fungi.  It is accompanied by a set of notes for the teacher, and a notes outline for the student.  Students will fill in their outline as the lesson is being presented.

Topics covered are:

1.   What are the fungi?

2.   Characteristics of fungi.

3.   Fungi are heterotrophs.

4.   Methods of food getting in the fungi.

5.   What environment do they prefer?

6.   The structure of fungi:  hyphae, mycelium, fruiting bodies, spores, rhizoids, stolons.

7.   Label the structures of a typical bread mold.

8.   Reproduction in fungi:  fragmentation, budding, spores production, asexual, and sexual reproduction.

9.   Kinds of fungi:  The four phyla are named and examples given for each phylum.

10.  Life cycle of the common bread mold.

11.  Phylum Zygomycota

12.  Phylum Ascomycota

13.  Phylum Basidiomycota

14.  Phylum Deuteromycota

15.  The Ecology of the Fungi: saprophytes, parasites, decomposition.

16.  Symbiotic relationships of fungi:  mutualism, commensalism, parasitism.

17.  Lichens and Mycorrhizae

I am also just about finished with a new FREE product on this topic, so stayed tuned for that.  I will add it to the list of freebies at the top left of my blog as soon as possible.

Happy Teaching!

Pumpkin Chemistry and The Haunted Library

What do you get when you cross the following: anatomy and physiology students, chemistry students, the school library, Halloween, the science club, and the Make-A Wish Foundation?

Just complete science FUN!!

Each year at our school, our students who are enrolled in either Anatomy and Physiology or Chemistry are required to carve a pumpkin with a theme that corresponds to the class that are taking.  As you would expect, some of the students go all out and bring in some really amazing creations, while others just do the bare minimum.  But, it always turns out to be a great day, and all involved have a lot of fun.

The library transformed!

All members of the science club stay after school one day and transform the library into "The Haunted Library"!!

The librarian is a great sport to allow us to do this to her library!

After the library has been decorated, all of the participating students bring in their carved pumpkins to put on display.  Next, you turn on the creepy music and turn on the ghosts that fly across the room, and you have a haunted library!

What did they do to my skeleton?

During the day, all students in our school are given the opportunity to visit our haunted library.  Each student pays $1.00 for admission.  And since the students are allowed to leave class (with teacher permission) to visit the library, you can well imagine that every kid in school is begging their teacher to take them to the library.  All of the money we raise goes to the Make-A-Wish Foundation.  I am proud that this year we were able to donate over $1000 to this wonderful organization!

Here are some of the pumpkins that were created for this year's haunted library.  I saved my favorites for the very last!

I will start with the one that my own daughter created!  Have you seen the movie, "Up"?  She carved the house from the movie into the bottom pumpkin, and add three helium balloon pumpkins on top.  On the left, is the pumpkin with the info from the periodic table about helium.

This one was created by an anatomy student.  Each bone in the hand and arm was clearly and correctly labeled.  Very cute!

This student did a great job carving a brain!

It's water with a bat-smile!

With my flash....

In the dark....

A model of an atom....

Carbon Dioxide....

We had two 

Einsteins!

 

A few of our special effects....

I loved this "ScArDy" Cat!

Very clever!

This student carved a pretty good heart!

And now for my very favorite!  This student did an amazing job carving a human fetus, and then placed it inside Mom's tummy!

I hope you have enjoyed this post.  It takes an incredible amount of work to pull this off, but the students loved it, and we raised so much money for a very worthy cause!  Win/win for all involved!

Happy Teaching!!

Discovery Education

I have spent the first part of this morning looking at the Discovery Education web site.  If you have never seen this site, and you teach school, you should head there right now!  It has free lessons and teaching materials for all subject areas and all grade levels.  Of course, I spent my time perusing the science section for grades 6 - 8 and 9 - 12.

Each lesson includes the following:  Objectives, Materials, Procedures, Discussion Questions, Evaluation, Extensions, Suggested Readings, Links, Vocabulary, and Standards.  Wow!!  Everything the teacher needs!

Here are some of the lessons I really liked for middle school students:

Robots:  The lesson centers around how robots will improve life for humans, especially those that have disabilities.

Transition Metals:  Students will identify and describe transition metals, discuss alloys and their benefits, and research one common alloy, its composition, properties, and uses.






Here are some of the lessons I really liked for high school students:

Underwater Forensics:  Students will discover how a team of scientists uncover the facts about a shipwreck, describe the roles of scientists and technicians on an underwater forensics team,  research a shipwreck, and demonstrate understanding of why such incidents occur.

Galileo's Dialogue:  Students will understand the following:

•	Galileo's conclusions about the position of Earth in the solar system raised objections from the Church.
•	Galileo lived at the beginning of a period in which scientific inquiry flourished.

As you can see, there are some really great activities on this site.  I hope you will find some useful lessons for your particular teaching situation.  Happy Teaching!!

Lab: Gas Exchange in Respiration

Gas Exchange in Respiration:

Qualitative Observation of Carbon Dioxide Release

It is the time of year for teaching photosynthesis and respiration to my biology students.  I think that all biology teachers will agree that these are difficult concepts to teach to our students.  Other than genetics, I think that the topics of photosynthesis and respiration may be my favorite topics to teach.  I enjoy the chemistry aspects, and I especially enjoy sitting back and marveling at how beautiful these two processes are.  I really get excited in my classroom and can often be heard saying, "Isn't it cool how this works?!"

Which do you teach first?  Personally, I like to teach respiration first.  After 28 years of teaching, I find that this approach works best for me.  I have tried it both ways, and now I always start with respiration.

It is so important to make sure that the students first have a firm grasp on the "big picture".  Emphasize the reactants and the products.  Make sure the students understand what the end result will be.  Then start adding in the details of the chemical reactions.  Once the student has a basic understanding of the relationship between these two processes, you can begin to add the details just like hanging ornaments on a Christmas tree.  As I move into the more complicated aspects of these chemical reactions, my students become more and more excited.  They quickly realize that they can really "see" the chemistry that is taking place.  

Unfortunately, I have found it very difficult to find good labs to reinforce the concepts of respiration.  I find photosynthesis labs to be more more effective.  At any rate, today I did this lab with my students:  Gas Exchange in Respiration.  The basic idea is to show students that living organisms give off carbon dioxide.  In the test tubes shown in the picture above, a small amount of phenol red has been added to each tube.  Glass beads are added to provide a barrier between the phenol red and the specimens that will be added to each tube.  As you look at the picture, the tube to the far left contains a piece of paper toweling that was dipped in a boiled yeast solution.  Tube 2 has paper toweling that was dipped into a fresh yeast solution.  Tube three contains 5-10 germinated seeds.  Tube four contains 5-10 dry seeds.  And tube 5 contains only the phenol red and no additional materials.  If the organism gives off carbon dioxide it will cause the phenol red to change from red to orange or yellow.  The tubes containing boiled yeasts and dry seeds will not show any change in the phenol red.  Fresh yeast and germinated seeds are actively respiring and will quickly cause a color change in the phenol red.

If you have great lab ideas for respiration, I would love to hear them!  Happy Teaching!

Gas Exchange in Respiration:

Qualitative Observation of Carbon Dioxide Release

Pinterest - The Latest Craze!

Are you a Pinterest addict yet?

If you have not taken a look at this site yet, then don't delay!  Head that way right now.  Pinterest is the latest craze and people are pinning like mad.  What are they pinning?  Just everything under the sun, from recipes, to clothes, to science products (!), to favorite books and movies.  Pinterest is like a huge bulletin board.  If you have something you like, you can pin it to a board that you have created.

I hope that you will check out all of my boards.  So far, I have created 34 boards.  Most of my boards are related to teaching science and you will find some great teaching materials there.  I have also found some terrific recipes on Pinterest and have pinned them to my "recipe" board.  The chocolate souffle recipe I found is to die for!

Check out my pin boards here:  Science Stuff on Pinterest!  I would love for you to become one of my Pinterest followers.

Happy pinning!