Problem 17 You have two flasks with broth m... [FREE SOLUTION]

Chapter 8: Problem 17

You have two flasks with broth media. One flask contains a species of cyanobacteria; the other contains \(E\). coli. Both flasks are sealed and incubated under optimal growth conditions for 2 days. Assuming the cell volume and metabolic rate of the bacterial cells are identical in each flask, why would the \(\mathrm{CO}_{2}\) concentration be higher in the \(E\). coli flask than in the cyanobacteria flask after the 2-day incubation?

Short Answer

Expert verified

The E. coli flask has higher CO鈧� because they produce it via respiration, while cyanobacteria consume CO鈧� for photosynthesis.

Step by step solution

Understand the Organisms

Cyanobacteria are photoautotrophs that utilize sunlight to perform photosynthesis, converting carbon dioxide (CO鈧�) into organic compounds and releasing oxygen. E. coli are heterotrophs which means they consume organic carbon sources for energy and release CO鈧� as a byproduct of cellular respiration.

Analyze the CO鈧� Consumption and Production

Cyanobacteria consume CO鈧� to produce organic material through photosynthesis, leading to a decrease in CO鈧� concentration within the flask. On the other hand, E. coli perform cellular respiration, consuming oxygen and producing CO鈧� as they metabolize their nutrient source.

Evaluate the Sealed Flask Environment

Since the flasks are sealed, there are no new inputs of gases. Cyanobacteria will continue to lower CO鈧� levels due to photosynthesis, while E. coli will continuously increase CO鈧� levels as a byproduct of their metabolism.

Compare the Final CO鈧� Concentration

Considering the metabolic processes, after 2 days, the E. coli flask will have a higher concentration of CO鈧� due to continuous production through cellular respiration, while the cyanobacteria flask will have lower CO鈧� levels due to photosynthetic consumption.

Unlock Step-by-Step Solutions & Ace Your Exams!

Full Textbook Solutions
Get detailed explanations and key concepts
Unlimited Al creation
Al flashcards, explanations, exams and more...
Ads-free access
To over 500 millions flashcards
Money-back guarantee
We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Cyanobacteria

Cyanobacteria, often referred to as "blue-green algae," are fascinating organisms that play a crucial role in the Earth's ecosystems. These microorganisms are classified as photoautotrophs, meaning they can produce their own food from light energy through the process of photosynthesis.

Cyanobacteria are among the earliest known life forms on Earth, significantly contributing to the oxygenation of the planet's atmosphere billions of years ago. During photosynthesis, cyanobacteria utilize sunlight to convert carbon dioxide and water into glucose, a type of sugar and primary energy source, while releasing oxygen as a byproduct.

Cyanobacteria absorb CO鈧� from their environment, actively helping to reduce its levels.
They thrive in various environments, including freshwater lakes, marine ecosystems, and moist soils.
Their ability to perform photosynthesis helps sustain food webs and supports life on Earth by producing oxygen and creating organic compounds.

E. coli

Escherichia coli, commonly known as E. coli, is a type of bacteria that naturally resides in the intestines of humans and other warm-blooded organisms. Unlike cyanobacteria, E. coli are heterotrophs, which means they cannot produce their own food and must rely on external sources of organic carbon for energy.

E. coli are known for their rapid growth and ability to adapt to various environments. In laboratory conditions, they are often used for research due to their simplicity and fast replication rate.

As heterotrophs, E. coli gain energy by breaking down nutrients through a process known as cellular respiration.
During this process, E. coli consume oxygen and produce CO鈧� as a byproduct.
Unlike cyanobacteria, E. coli contribute to the increase in CO鈧� levels within their environment.

Photosynthesis

Photosynthesis is the remarkable process by which green plants, algae, and certain bacteria like cyanobacteria convert light energy into chemical energy. This process is vital for producing the organic substances that other organisms rely on for food.

Photosynthesis involves chlorophyll and other pigments capturing light energy, typically from the sun, and using it to transform carbon dioxide and water into glucose and oxygen.

The overall equation for photosynthesis is: \[6CO_{2} + 6H_{2}O + light\:energy \rightarrow C_{6}H_{12}O_{6} + 6O_{2}\]
This process reduces CO鈧� levels as these organisms use it to build organic molecules.
Photosynthesis is not only crucial for the organisms performing it but also supports life on Earth by replenishing atmospheric oxygen.

Cellular Respiration

Cellular respiration is a metabolic pathway that breaks down glucose and other organic molecules to release energy for cellular activities. This process occurs in the cells of both plants and animals as well as many microorganisms, including E. coli.

Respiration can be aerobic, using oxygen, or anaerobic, not requiring oxygen. Here, we'll focus on aerobic respiration as it pertains to the given context.

The main equation for aerobic cellular respiration is:\[C_{6}H_{12}O_{6} + 6O_{2} \rightarrow 6CO_{2} + 6H_{2}O + energy\]
This process increases CO鈧� levels as glucose is broken down, with CO鈧� being released as a byproduct.
Cellular respiration is essential for converting the energy stored in glucose into adenosine triphosphate (ATP), the energy currency for cells.

Thus, in a sealed environment, organisms like E. coli that rely on cellular respiration will naturally increase CO鈧� concentrations as they consume nutrients for energy.

91影视

Short Answer

Step by step solution

Understand the Organisms

Analyze the CO鈧� Consumption and Production

Evaluate the Sealed Flask Environment

Compare the Final CO鈧� Concentration

Key Concepts

Cyanobacteria

E. coli

Photosynthesis

Cellular Respiration

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Biology Textbooks

Ecosystems

Communicable Diseases

Biology Experiments

Cellular Energetics

Cell Cycle

Substance Exchange

Study anywhere. Anytime. Across all devices.