Fermentation Lab Flashcards
In eukaryotic cells , the cellular respiration pathway is divided between _______ and _______
Cytoplasm and mitochondria
What is Aerobic respiration ?
When their is the presence of oxygen so the cytoplasmic products can enter the mitochondria
What is anaerobic respiration?
When their is little to no oxygen so the events in the mitochondria cannot happen = cytoplasmic product of glycolysis ( pyruvate and NADH) is metabolized by fermentation within cytoplasm.
What is the goal of fermentation
Recycle NAD* to ensure the constant supply of ATP by glucose catabolism ( breakdown)
What is a facultative anareobes ?
Can use aerobic but prefer anaerobic respiration.
( yeast = can use kreb’s cycle but prefer anaerobic alcoholic fermentation)
What is the overall metabolism of glucose by yeast?
C6 H12 06 ——> 2 CO2 + 2 C2 H5 OH
Reactant ——> waste + products
Glucose ——-> carbon dioxide + Ethanol
What is a synthetic medium?
- Nitrogen based medium
- Has usual growth requirements for yeast
- Is a source of nitrogen
- Has mineral
BUT - sugar need to be taken separately as a supplement
How to calculate the reaction rate of fermentation?
Volume of gas collected in the column over time
What are the steps of glucose fermentation metabolism?
1) glucose to pyruvate
C6 H12 O6 —> 2 CH3 COOH + 4H
2) pyruvate to acetaldehyde
2CH3 COCOOH —> 2CO2 + 2CH3 CHO
3) 4H added back to acetaldehyde to ethanol
2CH3 CHO + 4H —> 2C2 H5 OH
When does the glucose fermentation occur ?
When the first concentration of glucose is very high to kill competition by poisoning them. When competition is killed = ethanol —> acetaldehyde
What is yeast favorite sugar?
Glucose
Why does galactose not react ?
The lactose cant be hydrolyzed which means the backers yeast does not have lactase ( enzyme that breaks glycosidic bonds) galactose dont have transporters so it can’t enter the cell.
Why is NBM not reacting?
Doesn’t contain sugar
What is the independent and dependent variable of this lab
I : Types of sugar
D : Production of CO2 in fermentation tube
Why is NBM a negative control?
Because it showed that CO2 is created by fermentation and not something else.
