Unformatted text preview: part 3)
hr CELLULAR RESPIRATION
Remember that for every one mole of CO2 produced, there are
5.33 moles of ATP produced. So:
moles CO2 prod.* x 5.33 moles of ATP = moles ATP prod.**
1 mole CO2
*(from step 2) ** (use this value for part 4) 4. For comparisons between the yeast trials, the absolute rate of ATP production calculated in box #3 is
sufficient. For comparisons between the yeast trials and the corn seedling results a mass specific value is
required. Here the rate of ATP production (moles ATP / hour) must be expressed relative to the
respective weights of the organisms measured. The mass specific rate is obtained by dividing the absolute
rate of ATP production by the weight of the organisms giving: _____moles ATP____
gram organism x hour Biology 05LA – Fall Qtr. 2012 Lab 6 – page 5 Investigative questions addressed in this lab:
1. How will increasing the number of yeast cells affect the rate of ATP production by the cells (in
moles ATP / hr) if the sugar concentration in the experiment is held constant?
2. How will decreasing the amount of glucose affect the rate of ATP production by the cells (in moles
ATP / hr) if the amount of yeast in the experiment is held constant?
3. Will the yeast cells or the corn seedling have a higher metabolic rate when compared on a mass
specific basis (in moles ATP / gram organism x hr)? [Here, it might be important to consider that we
are actually comparing fully hydrated seeds to dry yeast.] Learning Goals/Intended Outcomes:
1) Be able to define the term metabolic rate.
2) Be able to recite the balanced equations for fermentation and cellular respiration.
3) Be able to explain why measurements of the rate of metabolic gas production or consumption can
be used as a valid measure of an organism’s metabolic rate. Your explanation should include
mention of the combined gas law and the balanced summary equations for fermentation and
4) Be able to explain why the use of balanced summary equations for metabolic studies of organisms
with complex diets (consisting of many different food groups) is impractical.
5) Be able to explain why it was necessary to compare the metabolic rates of the yeast and the corn
seedlings on a mass specific basis.
6) Be able to explain why it was necessary to keep temperature (and pressure) constant during our
7) Be able to explain why it was necessary to include measurements of killed cells/seedlings in these
8) Be able to present a factual and detailed explanation of why the yeast cells typically have a higher
metabolic rate than the corn seedlings.
9) Be able to explain why it might be important to consider the fact that yeast cells have mitochondria
when interpreting the results of experiments like the ones you performed?
10) Be able to explain why the corn seedlings for this lab were grown in the dark? Biology 05LA – Fall Quarter 2012 Lab 7 – Page 1 LAB 7: GENETIC TRANSFORMATION*
Genetic transformation is the act of altering the genotype of a cell by the introduction of DNA
molecules from an external source. In nature, the source of DNA can simply be a virus or a DNA
molecule that was released into the environment when a cell died and its DNA exposed. You probably
have already heard about genetic transformation in lecture (i.e., Griffith's experiments involving the
transformation of rough to smooth bacteria which lead to the discovery that nucleic acids were in fact
the genetic material by Avery et al.) Today genetic transformation is used in the laboratory to engineer
prokaryotes, animals, and plants for enhanced phenotypic characters and to repair deficiencies.
The transformation process itself involves two distinct steps:
1. the entry of foreign DNA into the cell and
2. the expression of the genes residing on the foreign DNA molecule.
In this experiment, you will be provided with
bacterial plasmid DNA as a source of transforming DNA.
Plasmids are very small, circular molecules that occur in
nature. Plasmids replicate independently inside the
bacterial cell. They have been manipulated by scientists
for movement of genes in and out of bacteria in the
The plasmid we are using in today's experiment is
called pUC118. It contains a gene that confers resistance
to the antibiotic ampicillin. Bacteria that contain the
plasmid can remain alive and grow in the presence of this
antibiotic. Bacteria without the plasmid stop growing and
may die in the presence of this drug. (Note: ampicillin is
a derivative of penicillin). pUC 118* bla gene replication
origin -lactamase * plasmid, University
The objective of today's experiment is to
of CA, #118
genetically transform ampicillin-sensitive (or susceptible)
bacteria into antibiotic-resistant bacteria. The addition of
a plasmid with an ampicillin-resistance gene will thus change the genotype and the phenotype of the
bacterial cell. Unlike the Stretptococcus (formerly Pneumococcus) studied by Griffith, Escherichia coli...
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This note was uploaded on 08/27/2013 for the course BIO BIOL05LA taught by Professor Abbottl during the Fall '12 term at UC Riverside.
- Fall '12