Bio Test 3?

idk what to write here anymore

Metabolic Pathway

A series of chemical reactions

Cellular Respiration

the series of reactions to get ATP from glucose

what is the equation for cellular respiration?

C6H12O6 → 6CO2 + 6H2O

why do you need to break glucose slowly?

if you were to break glucose’s bonds apart in 1 step, you’d explode

reduction

a molecule gaining high energy electrons and Hydrogen

Oxidation

A molecule losing high energy electrons and Hydrogen

What does Hydrogen have do with high energy electrons?

Hydrogen carries the high energy electrons

aerobic

requires oxygen

what 2 stages of cellular respiration are aerobic?

ETC and Krebs

anaerobic

doesn’t require oxygen

what stage of cellular respiration is anaerobic?

glycolysis

what is the first stage of cellular respiration?

glycolysis

energy investment phase

Take 2 ATP, turn them into ADP and put the Ps on glucose so it would be unstable and break in half

PGAL

1/2 a glucose (shown as C-C-C) and a P

NAD+

a molecule that can store energy longterm,turning into NADH

energy payoff phase

the bond breaking in the glucose releases energy, 4ADP take the phosphates and turn into 4ATP, 2NAD+ come and take some of that energy

pyruvates

C-C-C

what are the products of glycolysis?

net 2ATP, 2NADH, 2 pyruvates

where is most of the energy at the end of glycolysis?

pyruvates

What happens to each product of glycolysis?

4ATP- Used immediately

pyruvates- break the last bond to release energy, 2NAD+ takes the energy and turns into 2NADH, goes to Krebs

NADH- goes to Krebs

WHere does Krebs take place?

Matrix of the mitochondria

Acetyl

C-C

What happens before Krebs?

CoenzymeA (CoA) is added to acetyl to create acetylCoA and gets taken to Krebs

What takes acetyl through Krebs?

C-C-C-C (Car)

What happens in Krebs?

The Car bonds to the acetyl, making citric acid. The bonds in the acetyl are broken, releasing energy.

What happens to the Cs?

They are turned into CO2, a garbage molecule, and released to the air

What takes the energy in Krebs?

NAD+, turning into NADH

What is reduced/oxidised in Krebs?

acetyl-CoA → oxidised

NAD+ →reduced

Products of Krebs

8NADH

2ATP

6CO2

2FADH2

Where is most of the energy stored at the end of Krebs?

8NADH

what are the different names for ETC?

Oxidative phosphorylation, Electron Transport Chain

where does ETC take place?

the inner membrane of the mitochondria

Why is the inner membrane folded?

It increased the surface area, so there’s more space for ETC, so more ATP

intermembrane space of the mitochondria

the space between the inner membrane and the other membrane

What first begins in ETC?

NADH dumps out the NAD+, high energy electrons, and H+s

Where do they high energy electrons go?

they jump to the transport proteins until they reach O2

Why do the electrons go there?

The proteins are electronegative, so the electrons are attracted to them. Each protein is more and more electronegative, and O2 is the most electronegative

Where do the H+ go?

The H+ go into the matrix, but the electrons power the transport proteins, the all the H+ go to the intermembrane space

NADH’s job in ETC

Binds to 1st protein and on in ETC, pumps out maximum amount of H+

FADH2

Can only bind to the 2nd protein and on in ETC, less efficient bc it can bind to less proteins

What happens after all the H+ go to the intermembrane space?

the H+ want to diffuse, but they can’t

ATP Synthase

a protein that the H+ go through. It spins, converting the potential energy of the H+ into kinetic energy. The energy is used to convert ADP → ATP

weight loss drug

a drug that stuck itself to the inner mitochondrial membrane and acted like a channel protein for H+, created a leaky membrane

leaky membrane

a membrane where the H+ doesn’t have to go through the ATP synthase to diffuse, so the cells has to work harder and use more glucose to get energy

why was the weight loss drug bad?

because the membrane was leaky, more energy was released into the body as heat instead of being used for ATP. This overheated the body, and people died

substrate-level phosphorylation

creating ATP through an enzyme. Only produces 1-2 at a time, inefficient, happens in glycolysis and Krebs

Why is cyanide bad for you?

cyanide blocks the electrons in the final protein from jumping to O2, so the electrons are stuck -→ no ATP production → you die

Oxidative phosphorylation

Creating a lot of ATP at once through the ETC, extremely efficient, makes around 30 ATP

Why is ETC aerobic?

If there is no O2, the electrons can’t jump to it, so they’re stuck. If the electrons are stuck, NADH can’t dump out more

Why is Krebs aerobic?

If the ETC is stuck, the NADH can’t become NAD+, so there isn’t enough for Krebs.

Fermentation

Regenerate NAD+ in cytoplasm to keep glycolysis going in absence of O2

Alcohol fermentation

After glucose is turned into 2 pyruvates, the NADH is converted back to NAD+ (oxidized) to go back to the beginning of glycolysis.

What happens to the pyruvates in alcohol fermentation?

the pyruvates break 1 bond of C, and it’s released as CO2. With the H from NADH, the pyruvates turn into ethanol

equation for alcohol fermentation

  2 Pyruvate  → 2 CO2 + 2NAD+ + 2 Ethanol

what creature can do fermentation?

yeast

Making wine

pick out grapes w/ yeast on them, mash them up, and put in a sealed container. Yeast eat the sugar on the grapes, so they do cellular respiration. After a while, the yeast have no more O2, so they begin to ferment.

facultative anaerobe

can live with or without O2

obligate anaerobe

can’t live with O2

what are the two ways humans use yeast?

bread and wine making

how do you make bread using yeast?

when kneading the bread dough, the yeast inside have no O2 so they ferment. In the oven, the alcohol dissolves and the CO2 is released, making the bread rise.

lactic acid fermentation

Creating lactic acid because of the absense of O2

What creatures use lactic acid fermentation?

bacteria and humans

humans doing lactic acid fermentation

when doing extreme exercise, ATP and O2 is highly required. ETC and Krebs are shut down, and glycolysis can’t happen because there is not enough NAD+ to keep it going. The muscle cells turn the NADH into NAD+, and it makes lactic acid as well

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An enzyme pops the H off the NADH to the pyruvates, which creates lactic acid

What happens after humans do lactic acid fermentation?

cells send toxic lactic acid to the liver, where it turns back into pyruvates to be used for ATP

Oxygen Debt

When the body does not have enough Oxygen to operate Krebs and ETC

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Body makes a little ATP via glycolysis

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After lack of O2, breathe heavily to repay debt and power Krebs and ETC

Formumla for Lactic acid Fermentation

2 pyruvates → 2 lactic acids

Yogurt production

Bacteria + milk are in a sealed container without O2

The pyruvates from the bacteria will become lactic acid, NADH → NAD+

THe milk would get sour

The acidity turns the milk chunky

what did prokaryotes do before there was O2 in Earth?

They would only do glycolysis

Cellular Respiration in bacteria

If bacteria has no O2, it has to resort to only. doing glycolysis. An enzyme takes NADH and pyruvates and pops the H onto pyruvates, making it lactic acid

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When there is O2, Bacteria do ETC between the cell membrane and the cell wall bc it has empty space. That’s where the H+ go

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