Ask Question, Ask an Expert


Ask Biology Expert

All living organisms must utilize energy to maintain themselves and to carry out life activities. The rate of energy utilization is known as the metabolic rate. Eukaryotic organisms used chemical energy to drive energy requiring life processes. We will measure metabolic rate in both an anaerobic and aerobic organism by measuring the amount of C02 gas produced by these organisms. We will use the Vernier CO2 gas sensor inserted into an environmental chamber in which the organism is fermenting or respiring.

The oxidation of glucose to form carbon dioxide and water liberate energy through the process of photosynthesis. In photosynthesis, green plants convert sugars into chemical energy with the help of the sun. The sugars provide stable form in which energy can be stored and transported. However, these energy is converted into another chemical form known as adenosine triphosphate (ATP). When ATP is split, energy is release for cellular work and the resulting molecule is known as adenosine diphosphate (ADP). ADP is reconverted to ATP with energy derived from sugars or other nutrients.

The flow of energy from solar radiation captured by plants (via photosynthesis) to its use by both plants and animals. This energy drives many fundamental life processes such as movement, growth, and reproduction. The release of energy from food molecules occurs by two biochemical pathways. The first is called fermentation. Fermentation usually occurs in the absence of oxygen and referred to being anaerobic. The other biochemical mechanism of energy release is called cellular respiration.

Respiration ( Plants and animals)

O2 + sugar ---------------------------> CO2 + H2O + ATP ( chemical potential energy)

Photosynthesis ( plants and plant like protists)

CO2 + H2O + light energy -------------------------> O2 + sugar


C6H12O6 + 2Pi + 2 ADP ------> 2 CH3CH2OH + 2 CO2 + 2ATP + heat
Glucose Ethanol

The equation shows that for every molecule of glucose consumed: two moles each of ethanol, carbon dioxide, and ATP are produced as well as heat. You will begin by measuring the rate of CO2 productoin by yeast undergoing alcoholic fermentation. This rate will be related to the rate of ATP production which is a reflection of metabolic rate of yeasts.

The experiment will address the following problems:

problem 1: How will increasing the number of yeast cells influence the metabolic rate of the yeast suspensions?

problem 2: How will substituting galactose for glucose influence the metabolic rate of the yeast suspensions ?

Preparation of Yeast Samples:

1. Set up the three fermentation samples in test tubes according to the values specified in the following table:

Tube Label Suspending solution: Weight Yeast (grams)
Volume, % age, and type
1 glu- 0.3 6 ml - 20%- glucose 0.3
2 glu - 0.6 6ml - 20% -glucose 0.6
3 gal - 0.6 6ml - 20%-galactose 0.6

Measure gas production by your samples. Measurement can proceed when the sugar/yeast mixture begins to bubble and the parafilm bulges upward.

1. Turn on Lab Quest recorder by pressing the silver button on the upper left hand side of the unit.
2. Pour the entire yeast mixture from the test tube into petri dish and place the dish inside the large environmental chamber. Attach the cover which should have one opening. Insert CO2 sensor intot he second opening.

problem 3

describe why measurements of an organism's rate of gas consumption or production can be used to estimate that organism's rate of ATP production.

problem 4

What is the comparison of the two quantities of yeast exposed to the same concentration of glucose (tube 1 and tube 2)?

problem 5

describe the results for the comparison of the trials run with 0.6 grams yeast and either 20% glucose and 20% galactose.

Cellular Respiration by Corn Seedlings

Cellular respiration is the main process of ATP productoin used by plants, animals, and many microorganisms. The use of oxygen in the conversion of sugars to CO2 and water releases much more energy stored in sugar than fermentation does. It is about 16 times as much ATP is generated from fermentation of the same sugar. The overall reaction is shown below
C6H12O6 + 6 O2 + 32 ADP + 36Pi -------> 6CO2 + 6 H20 + 32 ATP + heat
The measurement of the rate of CO2 production by aerobic organism provides a useful measure of its rate of energy production. We will use a Vernier CO2 gas sensor inserted into a closed system containing corn seedlings undergoing cellular respiration.
The data will be used to address the problem

problem 6:
In terms of the mass specific rates you find outd (g ATP/ gram of tissue x hour), did the yeast suspensions or corn seedlings have a higher metabolic rate?

Preparatoin of corn seedlings:
1. Obtain and weigh a 250 ml Nalgen bottle and record its weight. Tilt the bottle on its side and add about 25 corn seedlings with radicles, ranging from 1.0 to 3.0 cm in length.
2. Once the seeds are in the bottle, weigh the bottle with seeds. The weight of seeds can then be find outd and recorded on worksheet.
Measurement of CO2 production

1. Insert CO2 sensor into the neck of Nalgene bottle.
2. Measure the CO2.

Biology, Academics

  • Category:- Biology
  • Reference No.:- M924398

Have any Question? 

Related Questions in Biology

Of the four chambers of the human heart which has the

Of the four chambers of the human heart, which has the thickest walls, and why? Why can you not catch the same cold twice, but a new cold will make you sick for a week or two? What is the key step in spermatogenesis that ...

1 if humans are in the same class as domestic cats we must

1. "If humans are in the same class as domestic cats we must also be in the same order." True or False? Explain. 2. Explain in your own words how, from an evolutionary standpoint, a desert spring and an island in the oce ...

What is the state of the issue of genome engineering

What is the state of the issue of Genome engineering technology in Sweden? Are there laws governing the it? Is there a high level of controversy in Sweden over the ethical issues of Genome engineering technology? Why/why ...

Suppose you are performing an experiment in which you must

Suppose you are performing an experiment in which you must use heat to denature a double helix and create two single stranded pieces. Based on what you know about nucleotide bonding, do you think the nucleotides will all ...

Health records managementdirections be sure to save an

Health Records Management Directions : Be sure to save an electronic copy of your answer before submitting it to Ashworth College for grading. Unless otherwise stated, answer in complete sentences, and be sure to use cor ...

Suppose you bring 100 pounds of groceries into your home

Suppose you bring 100 pounds of groceries into your home each week. Please estimate how many pounds of each type of waste leaves your home. Does this add up to 100 pounds? Where do the various forms end up?

Explain how stems cells are can be used to treat diseases

Explain how stems cells are can be used to treat diseases and injury, with special focus on spinal cord injuries.

In an experimental template having perfectly placed 5

In an experimental template having perfectly placed 5 nucleosomes there is a single EcoR1 site buried near dyad axis of the 3rd nucleosome. Is it possible for a modeller to make this site accessible without disturbing an ...

Assignment biology concepts and investigations marielle

Assignment: BIOLOGY CONCEPTS AND INVESTIGATIONS. MARIELLE HOEFNAGELS. THIRD EDITION 1. (CHAPTER1) Imagine that you are a scientist working with one of the first research teams sent to the planet Mars. One day, while digg ...

What does precautionary principle mean how would you apply

What does precautionary Principle mean. How would you apply the concept of the Precautionary Principle to the unrestricted allowance of endocrine disrupters in consumer products?

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro

Describe what you learned about the impact of economic

Describe what you learned about the impact of economic, social, and demographic trends affecting the US labor environmen