The main difference between yeast and bacteria is that yeast is a eukaryote whereas bacteria are prokaryotes. Further, yeast belongs to the kingdom Fungi while bacteria belong to the kingdom Monera. And yeast has membrane-bound organelles, but bacteria has no membrane-bound organelles. Moreover, some of the other differences between yeast and bacteria cells are that chitin is the main component of the yeast cell wall but, murein is the main component of the bacterial cell wall. Further, yeast has a single nucleus per cell, but bacteria do not have a nucleus.
Yeast and bacteria are unicellular organisms. A cell wall surrounds both cells, and both yeast and bacteria may undergo anaerobic respiration.
Key Areas Covered
1. What is Yeast
– Definition, Characteristics, Importance
2. What are Bacteria
– Definition, Characteristics, Importance
3. What are the Similarities Between Yeast and Bacteria
– Outline of Common Features
4. What is the Difference Between Yeast and Bacteria
– Comparison of Key Differences
Key Terms: Bacteria, Cell Wall, Cell Structure, Metabolism, Yeast
What is Yeast
Yeast refers to a microscopic fungus, consisting of single oval cell that reproduces by budding, and converts sugar into alcohol and carbon dioxide in a process called ethanol fermentation. Generally, yeast is colorless. Though it is a unicellular organism, yeast is a eukaryote. Therefore, it contains a nucleus and membrane-bound organelles. Yeast grows on plants and warm-blooded animals in a symbiotic relationship. A few of them may be parasitic such as Candida albicans, which causes vaginal yeast infection. One of the most characteristic features of yeast is its asexual reproduction method known as budding.
Yeast undergoes external digestion by secreting digestive enzymes onto an organic material in the environment and absorbing nutrients through the cell wall. Some uses of yeast are in baking and beer production due to its ability to undergo ethanol fermentation.
What is Bacteria
Bacteria refer to a member of a large group of unicellular microorganisms, containing a cell wall but, lacking organelles and an organized nucleus. The cell wall of bacteria is made up of peptidoglycans called murein. Bacteria contain 70S ribosomes, and bacterial DNA is arranged in the nucleoid. Some bacteria may contain flagella for their movement. The basic shapes of bacteria are coccus, bacillus, and spirillum.
The main reproduction method of bacteria is the asexual reproduction, which occurs by binary fission. They contain structures called pili that assist conjugation, the sexual reproduction method of bacteria. Bacteria may cause diseases such as TB, pneumonia, tetanus, cholera, food poisoning, and sore throats.
Similarities Between Yeast and Bacteria
- Yeast and bacteria are unicellular organisms.
- They have a cell wall made up of polysaccharides.
- Both undergo anaerobic respiration.
- Both undergo extracellular digestion.
- They are heterotrophs.
- They undergo asexual and sexual reproduction.
- Both can be either saprophytes or parasites. Hence, both may cause diseases in plants and animals.
- Antibiotics are used to treat both yeast and bacterial infections.
Difference Between Yeast and Bacteria
Yeast: A microscopic fungus, consisting of single oval cell that reproduces by budding, and capable of converting sugar into alcohol and carbon dioxide in a process called ethanol fermentation
Bacteria: A member of a large group of unicellular microorganisms, containing a cell wall but, lacking organelles and an organized nucleus
Yeast: Made up of chitin
Bacteria: Made up of murein
Yeast: Has a single nucleus per cell
Bacteria: No nucleus
Yeast: Has mitochondria, ER, Golgi apparatus, lysosomes, etc.
Bacteria: No membrane-bound organelles
Yeast: Linear chromosomes
Bacteria: Single circular chromosome
Yeast: 80S Ribosomes
Bacteria: 70S Ribosomes
Under the Microscope
Yeast: Large cells; oval-shaped; has a budding cell
Bacteria: Small cells; spherical or rod-shaped; arranged in clusters or chains
Yeast: Ethanol fermentation
Bacteria: Either aerobic or anaerobic respiration
Bacteria: Mobile with flagella
Yeast: No pili
Bacteria: May have pili
Yeast: Mainly reproduce by budding
Bacteria: Mainly by binary fission
Yeast: Candidiasis, mycosis, urinary, and vaginal infections
Bacteria: Pneumonia, tetanus, TB, cholera, food poisoning, and sore throats
Yeast: Used in the production of beer, bread, and antibiotics
Bacteria: Used in the production of antibiotics and other useful chemicals
Yeast: Saccharomyces cerevisiae (baking yeast) and Cryptococcus neoformans
Bacteria: S. aureus, Lactobacillus sp., Bacillus anthracis, E. coli, etc.
Yeast is a eukaryotic organism while bacteria are prokaryotes. Both yeast and bacteria are unicellular organisms with a cell wall. Yeast contains a nucleus and membrane-bound organelles but, bacteria lack a nucleus or membrane-bound organelles. The main difference between yeast and bacteria is the cellular organization of both types of microorganisms.
1. “Yeast.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 27 Jan. 2017, Available Here
2. Vidyasagar, Aparna. “What Are Bacteria?” LiveScience, Purch, 23 July 2015, Available Here
1. “S cerevisiae under DIC microscopy” By Masur – Own work (Public Domain) via Commons Wikimedia
2. “Prokaryote cell” By Ali Zifan – Own work; used information from Biology 10e Textbook (chapter 4, Pg: 63) by: Peter Raven, Kenneth Mason, Jonathan Losos, Susan Singer · McGraw-Hill Education. (CC BY-SA 4.0) via Commons Wikimedia
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