Lab quiz 2 part two and small amount of three

“What is the purpose of respiration?”

To produce ATP (energy)

Aerobic respiration

Uses oxygen

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Do all microbes use oxygen as terminal electron acceptor

No

Cytochrome oxidase Complex function

Transfers electrons to the terminal(final) electron acceptor(reciver)

what do you call Enzyme that transfers electrons to oxygen

Cytochrome oxidase complex

Very reactive charged molecule

Free radical

Other names for Free radical

Superoxide

What are free radicals and known fact?

It when electrons does not properly bind to oxygen , creating Reactive charged molecules that makes deadyly product and disrupt cellular processes

Is talked about in Antioxidants

Superoxide dismutase (SOD) (fix free radical)

• Neutralizes oxygen radicals by converting them to hydrogen peroxide

• Indicates organism is capable of dealing with oxidative stress(damage done by free radical)

Breaks down oxygen radicals and convert them into hydrogen peroxide

superoxide dismutase

Catalase and know facts

• Converts Hydrogen Peroxide to Water and Oxygen

• Indicates organism uses oxygen as a terminal electron acceptor

1.) Catalase will go right after/needs superoxide dismutase while superoxide dismutase dose not

Breaks hydrogen peroxide into water and oxygen

catalase

when there radical and then Superoxide dismutase (SOD). What is the next molecule?

H2O2 hydrogen peroxide

after the conversion of hydrogen peroxide and then then the processes of Catalse. What next molcue?

water and oxen (H20 and O2)

purpose of Oxidase test and procces

Purpose:

Detects cytochrome c oxidase.

Process:

-Drip oxidase reagent on colonies

-Results can take ~5 minutes

Oxidase Test: Positive

-Blue color change

- cytochrome c oxidase is present, which means cytochrome c oxidase transfers electrons to oxygen to end of the electron transfer chain

Oxidase Test: Negative

-Clear/ yellow color

- Cytochrome c oxidase is absent which means it cannot combine electrons with oxygen at the end of the electron transfer chain

Catalase test purpose and process

Purpose: Detects catalase

Process:

-Drip hydrogen peroxide on colonies

-Immediate results

Postive- Catalase test

-Bubbles

-Catalase is present, since catalase converts hydrogen peroxide into water and oxygen (O2) → (O2) contributes to gas production, which makes the bubbles

Negative- Catalase test

-no bubbles

-Catalase is not present, which means it do not break down hydrogen peroxide and dose not deal with oxidase stress with catalase

Why does hydrogen peroxide fizz on wounds?

Catalase in cells breaks it H2O2, making water and oxygen- O2 makes gas production to bubbles

Glucose

Test Detects Cytochrome C Oxidase

Oxidase Test

Test detected catalase

Catalase Test

Glucose

Starting molecule used to make energy

Glycolysis

Pyruvate

2 ATP (glycolysis made it)

Fermentation (anaerobic “oxgen not present” and NOT EVERYTHING USE GLUCOSE)

Lactic acid (left) or ethanol (Right)

Krebs cycle (Oxgen is present- makes carries)

Electron transport chain (ETC) (Oxgen is present and final oxygenreciver)

Up to 36 ATP

Anaerobic (is a Category): Fermentation (one type/process in the category)

Partial breakdown of sugars

-small amount of energy  produced

-often in absence of oxygen

Aerobic (category): Respiration (one type in the category) process

Complete breakdown of sugars

-lots of energy produced

-often requires oxygen

What molecule enters fermentation or respiration?

Pyruvate

What is thioglycollate medium observed/used for

To observe bacterial growth based on oxygen, it also important to know that Different parts of the tube have different levels of oxygen present

Fluid Thioglycollate Medium

• Viscous, but not solid (LIKE HONEY).

• How; Sodium thioglycollate consumes Oxygen

• permits growth of  obligate anaerobes

Resazurin

A dye that indicates the presence of oxygen in thioglycollate medium

Resazurin: Reports on the presence of oxygen:

blue = oxidized 

pink = partly oxidized

colorless = fully reduced 

What does oxic mean?”

Oxygen present

“What does anoxic mean?

No oxygen

Oxic zone

Anoxic zone

Pink region indicates media is thoroughly oxidized. 

How do we grow and tell the difference between grow in response to oxygen?

Fluid Thioglycollate Medium (its a media)

what is culture

It when the bacteria GROWS in the media

(Not Culture → E. coli in a tube (not growing yet)

✅ Culture:→ E. coli growing on a plate )

Media

substances used to grow bacteria (broth, plates, slants, thioglycollate)

Obligate (strict) aerobes

Obligate (strict) aerobes

Cannot grow in the absence of oxygen because it requires oxygen for respiration

Obligate (strict) anaerobes

Obligate (strict) anaerobes

Is killed by the presence of oxgen

Facultative anaerobes

Facultative anaerobes

 It can grow in the absence of oxygen, but it works better when oxygen is present

Aerotolerant anaerobes

Aerotolerant anaerobes

It does not use oxygen but can tolerate it

Microaerophiles

Microaerophiles

It only grows when oxygen is in low concentration

Which organism requires low levels of oxygen?”

Which bacteria grow best when oxygen is present at low concentrations?

Microaerophile

Which organism does not use oxygen but can tolerate its presence?”

Which bacteria grow in the presence of oxygen but do not require it?”

Aerotolerant anaerobe

When fermentation partially breaks down the foods what dose it produce

Waste products ( like lactic acid in homaltic fermination or heterolcatic fermination ehtonal/CO2)

definition of fermentation

eating food in the absence of oxygen

What do bacteria need to perform fermentation

-carbon source (food)

- Carbohydrates like: Sucrose, Lactose, Glucose

Types of Fermentation

Homolactic fermentation→ Utilizes lactose to produce one byproduct [ Produces ONE product (lactic acid)]

Heterolactic fermentation →  Utilizes lactose to produce several byproducts [Produces MULTIPLE products]

What dose Hetero mean

Different

What dose Homo mean

Same

What products are made from Heterolactic fermentation

Carbon dioxide, ethanol, and lactic acid

What products are made from Homolactic fermentation

lactic acid

Why do bacteria stop growing over time in lactic acid fermentation?” and What happens as lactic acid accumulates(production of waste) during fermentation

1.) Too much lactic acid builds up

2.)when there to much lactic acid bacteria can tolater to a degree but once there to much the bacteria die

What causes the drop in bacterial population

acid accumulation

Homolactic Species/bacteria that produce only lactic acid

Lactobacilli

Heterolactic species/bacteria that produce multiple products

Leuconostoc

Streptococcus and Bifidobacterium

Which type produces only one product?

Homolactic fermentation

Which type produces multiple byproducts?

Heterolactic fermentation

What is selective media

fully inhibits one type of bacteria and allows the other to grow (example MRS agar “ a.k.a it like a plate)

What is differential media

 Allows multiple bacteria types to grow but look different once they do (example Thioglycollate medium)

is deMan-Rogosa-Sharpe (MRS) Agar a SELECTIVE or DIFFERENTIAL MEDIA

SELECTIVE

WHat bacteria/specimen dose MRS agar allow to grow, and what does it not

It allows Lactobacillus and Leuconostoc, but bacteria like streptococcus are inhibited

what dose MRS agar stand for and what is pH level

1.) deMan-Rogosa-Sharpe (MRS) Agar

2.) 6-6.5 ( ideal for Lactobacillus)

WHat dose Ph stand for

potential of Hydrogen

What indicates an acidic solution?”

High H⁺ (hydrogen ion/proton))

What indicates a basic solution?”

High OH⁻ (hydroxide ion)

What is neutral pH?”

Equal H⁺ and OH⁻

high pH (8–14)

Basic (alkaline)

pH 7

Neutral

pH (0-6)

Acidic

How is pH determined

when H⁺ and OH⁻ come togather to from water (H2O), what is left over determines it

pH (formula)

pH = −log₁₀[H⁺]