Assignment 5
Due February 7
1. File upload (2 points)
Fill out the relationships diagram that illustrates the process of cellular respiration by
writing the letter of the correct answer in the box. (Download the image and label the
boxes). When you think that all of the answers are correct, do a screen shot of the
diagram and submit it to WebAssign. Note: all answers on the page must be correct to
receive credit for this question.
2. Multiple-choice (1 point)
Why was KOH added to the respirometer?
to absorb water
to absorb oxygen
to absorb carbon dioxide
to release oxygen into the chamber
to release carbon dioxide into the chamber
3. File upload (2 points)
Using the animation of a bubble moving through the pipet, fill in the missing values in
the column “Oxygen consumed at 23 o C”. (You can move the playbar slowly to see the
value at each time point.) Also note behavior of the mouse at both temperatures.
Time
1 min
2 min
3 min
4 min
5 min
6 min
7 min
Behavior observed
during the movie
Oxygen consumed at
23o C (ml)
Oxygen consumed at
18o C (ml)
2.4
4.9
7.2
9.7
9.7 +2.5*
9.7 + 5*
9.7 + 7.5*
Use the online plotter to graph accumulative oxygen consumption at each time point.
(Time is an independent variable, so be sure to place it on the X axis). You can have
two sets of Y values, so plot oxygen consumption at both temperatures on the same
graph. To add an additional column of data, select "Add Column" from the Table pulldown menu. For full credit, label each of your column headings. Capture an image of
your graph (and graph table) and submit it to WebAssign.
4. Fill-in-the blank (2 points)
Determine the rate of oxygen consumption at each temperature for comparison. Then
divide the higher rate by the lower rate to obtain the difference (ratio) between the two
temperatures. Round off your answer to the nearest 0.1.
It can be concluded that mouse respiratory rate _____ (increases or decreases) when
temperature is lowered. In this experiment, there was a ____ fold difference in
respiratory rate at the two temperatures.
5. Multiple-choice (1 point)
Based on you observations of mouse behavior, how did mouse activity differ at the
lower temperature?
The mouse utilized more energy trying to escape at the lower temperature.
The mouse utilized less energy at low temperature because it was asleep.
The mouse ate more food at the lower temperature.
The mouse expended energy by shivering at the lower temperature.
There was no difference in behavior at the two temperatures.
6. Essay (3 points)
Write a short essay that discusses the following questions:
a. How would the rate of oxygen consumption differ for a reptile of the same size as
the mouse at room temperature (23o C)?
b. What would happen to the rate of oxygen consumption if the reptile were cooled
to 18°C?
Justify your answers to receive full credit.
7. True/false (2 points)
Write true or false in each space:
____ The purpose of the blank in the seed germination was to determine the water
level in the tube under conditions in which no respiration could occur.
____ The seeds in treatment group 2 were heavier than those in treatment group 1
because they absorbed carbon dioxide during the 2-day trial period.
____ A good hypothesis for this experiment is “Germination increases the oxygen
consumption of seeds.
____ In the seed germination experiment, the tube with soaked seeds was the
experimental group and the tube without seeds was the control.
8.Multiple-choice (1 point)
What is the main reason that the seed germination experiment lasted for two days, but
the mouse experiment lasted for only 7 minutes?
Plant cells have a much lower rate of cellular respiration than animal cells.
Most plant cells produce more ATP than animal cells in a long time period.
Soap bubbles in a pipet move faster than water in a test tube.
Plants, unlike animals, do not breath air.
Seed germination is a slow process.
9. File upload (4 points)
Download this image of a real mitochondrion and label the following parts:
matrix
outer membrane
inner membrane
cristae
Submit your labeled image to WebAssign in .jpg or .png format.
10. True/false (2 points)
Review the animation on ATP synthase, and read this article on mitochondrial
Diseases. Then answer the following questions:
____ If ATP synthase did not function, ATP would accumulate to high levels within
the cell.
____ The ATP synthase complex rotates when a hydrogen ion passes through it.
____ At least 1 in 4,000 people have a mitochondrial disease.
____ There are only a few types of mitochondrial diseases.
11. Essay (2 points)
Examine the graph below, then write a short essay that answers the following
questions:
a) What is happening at 120-160 minutes?
b) How do these events relate to cellular respiration and/or brown fat?
Oxygen consumption (blue) is shown as a measure of metabolic rate during arousal
after hibernation. Body temperature (red) is shown for the rectum (red-closed circles)
and cheek pouch (red-open circles). The animal is a golden hamster, Mesocricetus
auratus. (Lyman, 1948)
12. File upload (3 points)
Based on your observations in the fermentation videos. complete the following table:
Amount (ml) of CO2 generated in fermentation tubes
Time
Yeast only Yeast + glucose Yeast + lactose Yeast + sucrose
0 min
0 ml
0 ml
0 ml
0 ml
5 min
0.1 ml
0.5 ml
10 min
0.2 ml
1.3 ml
60 min
0.4 ml
5.5 ml
Use the on-line plotter to graph time vs. amount of CO2 generated for the fermentation
tubes containing glucose, lactose, and sucrose. Make additional Y columns to place all
3 time curves on the same graph, and use lines to connect the dots. For full credit, label
each of your column headings. Capture an image of the graph (and plotter table) and
submit it to WebAssign.
13. Fill-in-the-blank (2 points)
Based on the results of the fermentation experiment, yeast utilized the sugar ____ most
efficiently and the sugar ____ least efficiently.
14. Multiple-choice (1 point)
What is the most likely reason that yeast plus one of the sugars in the fermentation
experiment produced almost no carbon dioxide?
This sugar does not contain any glucose molecules.
This sugar contains too many glucose molecules for efficient digestion.
This sugar does not occur in nature (was manufactured by chemical means).
Yeast does not contain an enzyme to digest this sugar.
None of these is a likely reason.