Cellular Metabolism Lab
We will walk through the steps of Cellular Respiration in this activity. Please do not skip ahead or leave out steps. Fully taking the time to cut out and arrange the shapes and answer attached questions will help you to gain a deeper understanding of cellular respiration (the process of making energy, ATP, the major contributor to our overall metabolism).
Grading Notes: You can either 1) Print out this document, add your answers and shapes to it, then scan the entire document for grading, or 2) Answer the questions on this template and upload images from your camera to the specified locations below. All blanks, images, tables, labels, etc will be part of your final grade.
Before you begin, cut out all of the shapes on the accompanying document. Also, you will need five pieces of paper, label one sheet of paper with one of the four steps of aerobic respiration and one for anaerobic respiration. You should have a sheet labeled; glycolysis, formation of acetyl-Co A, Krebs (Citric acid cycle), electron transport chain, and anaerobic respiration.
1. Glycolysis
a. To begin, cut out six carbon circles from the shapes sheet and arrange them to form glucose, place them on your glycolysis sheet.
b. Glycolysis is the splitting of glucose. To better understand this process, answer the following questions.
i. Where does glycolysis occur? _________________________________
ii. We began with glucose which is a ___ -carbon glucose molecule.
iii. After ten separate reactions glucose is split into two ____________ molecules which are ___-carbon molecules.
c. Now cut your glucose molecule into 2 pyruvate molecules.
d. Insert an image of your two pyruvate molecules on the glycolysis sheet below.
e. The energy released during the breakdown of glucose causes two products to be made. The first product is two _______________ molecules which are which are used as reversible energy carriers. The second product is two _______________, which is usable energy for the cell.
f. Write out the final products of glycolysis.
Glucose _____________ + ______________+ __________________
g. Using your cut out NADH molecules send two of them to your electron transport chain sheet to represent the NADH produced in glycolysis during aerobic respiration. (Don’t glue them just organize them)
2A. In the absence of Oxygen
What happens after glycolysis is determined by the availability of oxygen.
a. In the absence of Oxygen (O2), pyruvate goes through ______________________ cellular respiration. This uses pyruvate from glycolysis to yield two products.
b. Where will this reaction occur in the ____________ of the cell?
c. On your anaerobic sheet use one of your premade pyruvates and NADH molecules.
d. Using an arrow, show the products of anaerobic respiration, which are _________ and _____________.
e. Insert the image of your anaerobic sheet below.
f. What is the fate or where does each of these products go?
2B. In the presence of Oxygen—Formation of Acetyl-Co A
a. In the presence of Oxygen (O2), pyruvate would instead go through ___________cellular respiration.
b. Using your formation of acetyl-co A sheet, place your pyruvate plus co-enzyme A on the left side of the arrow. On the right you will put the products of this step, making the formula for this step.
c. This reaction occurs in ________________ of the cell?
a. Here pyruvate bonds with __________________ to form acetyl co-enzyme A.
b. The excess carbon are bonded to ___________ too form two _______________ and the excess energy is stored in two ___________________ molecules.
c. Acetyl Co-enzyme A can enter into the _________________ cycle.
d. Insert your completed Formation of Acetyl-Co A sheet here.
e. What happens to each product of formation of Acetyl-co A?
f. Once completed, if any of the products needs to move to another part of aerobic respiration please move it to that sheet.
3. Krebs Cycle (Citric Acid Cycle)
The acetyl Co A is moved into next set of reactions, the Krebs’s cycle.
a. Krebs Cycle occurs in __________________ of the cell.
b. Below label the specific location in the organelle where the Krebs’s cycle occurs.
c. On your Krebs’s cycle sheet create the formula using the available shapes. Remember, reactants on the left of the arrow and the products on the right. You can draw in your “+” signs and arrows.
d. Insert the image of your Krebs’s cycle sheet below.
e. Complete the products and their fate table below.
| Products | Fate |
| Insert products here | Insert the fate of each product here |
Table 1: Products of Kreb’s Cycle and their Fate
f. Make sure to move any products that go to other aerobic respiration reactions on the appropriate sheet.
4. Electron Transport Chain (Oxidative Phosphorylation)
The final reaction of aerobic respiration uses energy harvested elsewhere to generate ATP.
h. Place the NADH and FADHs (if any) that have come here from the previous aerobic steps on your electron transport chain sheet. (don’t glue them)
i. Fill in the table below. This will remind you how many you NADH and FADH2 molecules you should have and where they come from.
| Glycolysis | Intermediate Step | Krebs Cycle |
| How many NADH and FADHs came to the electron transport chain from Glycolysis? | How many NADH and FADHs came to the electron transport chain from the intermediate step? | How many NADH and FADHs came to the electron transport chain from Krebs Cycle? |
Table 2: The Sources of NADH and FADH2 in Aerobic Respiration
j. The Electron transport chains are located within the __________________ of the mitochondria.
i. Label this additional region on the mitochondria pictured below.
k. Here ____ ions are removed from ___________ and _____________.
l. Cleave the H+ ions from each of your temporary receptors that have been supplied by previous reactions and placed them in the appropriate location of the image on the last page of this assignment.
m. Cut out and place the integral proteins on the inner membrane of the mitochondria on the last page of this assignment.
i. Number the inner membrane proteins I-IV (the textbook only highlights 4, so you’ll have a shape left over)
ii. Label ATP Synthase
n. Cut out and place the ADP and Phosphate group molecules within the matrix near ATP Synthase (You do not have to use all of these, just enough to show understanding)
o. Insert your image of the electron transport chain below.
ETC Summary
a. Where are the H+ that were removed from the temporary receptors, were pumped to ___________ part of the mitochondria? Creating an area of __________ concentration on the outside of the ____________ membrane.
b. At the same time, the _____ ion is also released from the temporary receptor. These ions are moved along five inner membrane proteins to drive the movement of the H+ ions.
c. H+ can leave the area of high concentration by traveling through the _______________, which places them back into the matrix of the mitochondria.
d. The energy generated by the movement of the H+ is used by ATP synthase to synthesis ATP from _______ and _________ groups.
a. Cut out the e- and draw arrows to show how they move along the proteins in your picture on the last page.
b. Insert the picture below.
e. Both the electron and the H+ that are now back in the matrix (slide down ATP Synthase) are “captured” when they are bonded to ________________ forming _____________.
f. Roughly, for every NADH that enters the electron transport chain three ATP molecules are generated, while two are generated for every FAHD2 that enters the electron transport chain. Calculate how many ATP are generated during the breakdown of one glucose molecule for aerobic and anaerobic respiration. Make sure you identify where the energy is coming from in each type of respiration.
