Download Groupwork on Flow of Matter

Modeling the Flow of Matter from
Food Cells to Our Cells
Put yourself in the frame of mind to openly discuss ideas about science and
what might be going on about things that we cannot see.
•As a group you will work for the next two weeks to construct a model of your ideas on
how matter flows from our food’s cells to our cells. At the end of this unit each of you
will construct your own INDIVIDUAL models as the final product of this unit.
• Remember to follow the rules of Deliberation:
1. Gather Knowledge to develop shared group knowledge toward solving
a common problem.
In this phase you’ll want to make sure you:
A. Hear everyone’s ideas.
B. Support each other to take risks in your thinking.
C. Ask each other questions.
D. Understand and offer different ideas.
2. Make a Decision on the course of action.
In this phase not everyone has to agree on the ideas, but everyone
needs to agree on which ideas to try out first.
3. Reflect on your course of action and Revise your ideas if necessary.
______________________________________________________________________________
Your group will need to work on the following ideas.
Part 1 – The diversity of life in our foods!
Research and decide on a meal (have fun!) that includes food items
from or produced by:
A. a plant
B. an animal
C. a bacterium, and
D. either a fungus or a protist
Example menu: a cheeseburger on a whole wheat bun
whole wheat bun contains:
• sugar and wheat from plants
• milk and butter from an animal
• yeast is a fungus
burger contains:
• muscle from an animal
cheddar cheese contains:
• milk from an animal product
• bacteria
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Page 1 of 4
Part 2 – Cells and cellular structures make up our foods and ourselves!
A. What scientific theory states that all organisms are made out of cells?
B. Draw and label a representative cell and its organelles from each type of
organism that produced your food. Only one plant cell, one animal cell, and
one bacterial cell are required. If you have extra time, try drawing one fungal
or protist cell (this is optional and extra credit!). Remember: humans are
animals, so our generic animal cell is also the type of cell that our food is
headed to in our bodies!
Example:
whole wheat bun:
• sugar and wheat are products of plant cells
• yeast fungal cells may be used to make the bread rise
burger:
• beef contains animal cells
cheddar cheese:
• milk is the product of animal cells
• bacterial cells are used to ferment the milk into
cheese
Make sure to include and label (if present):
•
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•
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cell wall
extracellular
matrix
plasma membrane
nucleus
ribosomes
rough and smooth
endoplasmic
reticulum
•
•
•
•
•
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Golgi body
vacuoles
lysosomes
plastids (See Lab
02: chloroplasts,
amyloplasts,
chromoplasts)
mitochondria
cytoskeleton
•
•
•
•
•
cilia
flagella
nucleoid region
capsule
pili
C. Specifically what evidence from our lab activities do you have that, at least,
some of these structures are found in plant and animal cells?
D. Research and photocopy or print out an electron micrograph of a specific
type of cell that shows some cellular structures from an organism that your
food came from.
Example:
whole wheat bun -> research a wheat plant cell, or
whole wheat bun -> research a yeast fungal cell, or
burger -> research a muscle cell, or
cheddar cheese -> research lactococci or lactobacilli bacteria
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Page 2 of 4
Part 3 – Cellular structures are made of large biological molecules!
On the cell drawings from Part 2, label at least one organelle or cellular
structure in each cell type where you would find the following molecules. Be
sure to include the following terms where appropriate:
•
•
•
•
•
protein
cellulose (carbohydrate)
starch (carbohydrate)
glycogen1 (carbohydrate)
phospholipids (lipid)
•
•
•
•
triglyceride2 (lipid)
cholesterol (lipid)
DNA (nucleic acid)
RNA (nucleic acid)
 Specifically, what evidence do you have from our lab activities that some of
these molecules are found in these cellular structures?
1 – for cool picture of where glycogen is located in a cell see:
http://bio1151b.nicerweb.net/Locked/media/ch05/05_06Polysacchar_Glycogen.jpg
2 – for cool picture of where triglycerides are located in a fat cell see:
http://www.sp.uconn.edu/~terry/images/other/adipocyte.gif
------------------------------------------------------------------------------------------------Part 4 – Large biological molecules are made of smaller subunits!
Let’s look at how we break down these large molecules into smaller subunits
and how our bodies use these subunits to build the cellular structures in our
own cells.
__________________
A. First, let’s unravel, or denature, the secondary structure of our proteins in
the acidic environment (low pH) of the stomach.
Draw a diagram of how low pH works to denature a protein (see pg 48 in
textbook). Include in your diagram the following terms:
• Secondary structure
• Low pH (acidic environment)
• Hydrogen bonds
• Denaturation
• H+ (hydrogen ions)
• Primary structure
___________________
B. Second, let’s chew up all of our large biological molecules into smaller
subunits with water and enzymes in our small intestines.
Draw a diagram of how each of the large biological molecules is broken down
into smaller subunits. Use circles and lines to represent the subunits
connected by covalent bonds.
(Remember: polymer + water  monomers; this chemical reaction is
called “hydrolysis”).
Be sure to include the following terms:
•
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polymers
proteins
carbohydrates
lipids
nucleic acids
covalent bonds
hydrolysis
water
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•
Page 3 of 4
enzymes
monomers
amino acids
monosaccharides
nucleotides
glycerol
fatty acids
 Which polymer(s) from Part 3 above could not be broken down and are
eliminated as waste?
___________________
C. Third, after these smaller subunits have been absorbed by our small
intestines and circulated by the blood to all of the cells in our body, let’s see
how our own cells use these smaller subunits to make their own cellular
structures.
Draw a diagram of your ideas on how and where these smaller subunits are
then reassembled inside of your cells (our generic human animal cell).
(Remember: monomers  polymer + water; this chemical reaction is
called dehydration synthesis because we are taking water off of the
monomers in order to link them together to form a polymer).
Be sure to include the following terms:
•
•
•
•
•
•
•
•
•
monomers
amino acids
monosaccharides
nucleotides
glycerol
fatty acids
dehydration reaction
water
enzymes
•
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•
•
•
•
•
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proteins
carbohydrates
nucleic acids
lipids
ribosomes
cytoplasm
nucleus
smooth ER
___________________
D. In bullet points write down the whole process of this flow of matter in
words, from the diversity of life in our foods to how our cells use the matter in
our foods to build its own cellular structures. Include scientific theories and
evidence from our lab activities to support your ideas. This outline will help you
to write a full explanation for your model of how this biological phenomenon
works.
------------------------------------------------------------------------------------------------Part 5
Assemble together all of your materials and make sure all group members
have copies of the information. You will each now use this information to
construct individual explanatory models as homework in order to answer
the question, “Are we really what we eat?”
**Important!!! See the checklist handout below to make sure that you
include everything that you will need for your model.
Page 4 of 4
Name: ___________________________________________
Date: _________________
Checklist for Explanatory Model of the Flow of Matter from Food Cells to Our Cells
Scientists use explanatory models in order to be able to connect a series of ideas to explain how a natural
phenomenon might work. Their explanation includes the available evidence and existing scientific knowledge
up to that time. A model can then be tested and revised, if necessary, as new information is gained.
In this model you will concentrate on telling a story of the flow of matter from our food cells to a typical human
animal cell. A story flows from a beginning, a middle, and an end. This story will be mostly a picture book
story supported by words to help explain your point. The objective of this exercise is to help you to learn the
structure and composition of the many different types of cells found in living organisms and how they are all
related through the types of building blocks that compose their cellular structures. In addition, this will help
you to understand how your own cells (or any other organism that digests food for matter) use these important
building blocks.
This type of story is called an explanatory model, where you explain why you think a natural phenomenon
works the way it does through an evidence-based explanation (or story). Your evidence, in this instance, is the
information from your observations, measurements, and reliable resources from class, your labs and your text.
OK, so let’s get started! Here is a checklist of the following terms and concepts that you should include in your
story of how matter flows from our food cells to your own cells.
From Your Food:
 Menu is provided (0.5 points)
 Menu item ingredients are categorized into plants, animals, bacteria, fungi, and/or protists (1 point)
 One drawing of a representative cell and its structures from a plant, animal, and bacterium (7.5 points)
(Add in a correctly labeled fungal or protist cell for a bonus 2 points)
o Each cell drawing and its structures are appropriately labeled
o The following cellular structures include (if present):
 cell wall
 rough and smooth
 mitochondria
 extracellular
endoplasmic reticulum
 cytoskeleton
matrix
 Golgi body
 cilia
 plasma
 Vacuoles
 flagella
membrane
 Lysosomes
 nucleoid region
 nucleus
 plastids (chloroplasts,
 capsule
 ribosomes
amyloplasts, chromoplasts)
 pili
o In each cell type, each of the following molecules is labeled where it can be found in at least one
cellular structure. These include (if present):
 protein
 starch
 cholesterol
 cellulose
 glycogen
 DNA
 chitin
 phospholipids
 RNA
(optional)
 triglycerides
 Bonus: One picture from your research that shows some cellular structures of a specific type of cell (1
point)
See other side for “To Your Cells” checklist…
To Your Cells:
 Arrows are used to show the direction of the flow of matter and the stages of food processing (1
point)
o Ingestion
o Digestion
o Absorption and Circulation
o Elimination
 Diagram and explanation of digestion includes the following terms where appropriate (5 points):
o pH
o covalent bonds
o nucleotides
o denaturation
o protein
o lipids
o hydrogen bonds
o amino acids
o glycerol
o water
o carbohydrates
o fatty acids
o enzymes
o monosaccharides
o cellulose
o hydrolysis
o nucleic acids
 A drawing of a generic human animal cell is included (5 points)
o Diagram shows cell taking in the small molecules from the circulation
o Diagram explains how small subunits are reassembled by dehydration reactions to form
biological molecules inside of your cells or are used by the cell to harvest energy.
o Diagram includes labeled cellular structures where these reactions take place:
 nucleus
 mitochondria
 ribosomes
 smooth and rough endoplasmic reticulum
 cytoplasm
 Bonus: Diagrams of one plant AND one animal cell show how proteins made in the rough ER are
transported to either the plasma membrane, a vacuole, or a lysosome. (2 points)
 At least one supporting paragraph that gives an evidence-based explanation in complete sentences of
why we can say, “We are what we eat!”
Level of Evidence-Based Explanation:
Level 1
Level 2
Level 3
(1 point)
(3 points)
(5 points)
Level of Evidence-Based Explanation rubric:
Level 1 (1 point)
Level 2 (3 points)
o Student describes what happens
o Student describes how or partial
o
o
in each part of the model without
linking them together to explain
how or why we are what we eat.
Student describes, summarizes, or
restates each part of the checklist
without making a connection to
full causal story.
No references to established
theories or evidence from lab or
the text are used.
Score:
Comments:
/25 points
Level 3 (5 points)
o
why we are what we eat.
o Student links together some parts
o
of the model but not all.
Student addresses theoretical
components tangentially (nonspecifically) or does not reference
evidence from lab and the text in
their explanation.
Bonus:
/5 points
o
o
Student explains why we are what
we eat.
Student can trace a full causal
story for why a phenomenon
occurred. This is well supported
by diagrams in the model.
Student uses powerful science
ideas like the established cell
theory, and references to
evidence from lab and the text, to
explain observable events.