bballjake300

2+ Year Member
Jul 11, 2016
30
13
Status
Pre-Dental
Im getting confused because in the destroyer it says that the first enzymatic activity for digestion occurs in the stomach. However, I'm pretty sure the first enzymatic activity starts in the mouth with salivary amylase.

Another question, so I know glycolysis produces 2 ATP for each glucose molecule so can I say that 1 pyruvate produces 1 ATP and 1 lactate during lactic acid fermentation?
 

orgoman22

DAT DESTROYER
Lifetime Donor
Sponsor
Vendor
10+ Year Member
Mar 12, 2005
4,186
3,038
New York City
www.orgoman.com
Status
Non-Student
Im getting confused because in the destroyer it says that the first enzymatic activity for digestion occurs in the stomach. However, I'm pretty sure the first enzymatic activity starts in the mouth with salivary amylase.

Another question, so I know glycolysis produces 2 ATP for each glucose molecule so can I say that 1 pyruvate produces 1 ATP and 1 lactate during lactic acid fermentation?
First protein digestion starts in the stomach. Amylase does not digest proteins. It digests carbohydrates.

Glycolysis produces 2 pyruvates and 2 ATP's. Then pyruvate gets converted to lactate to continue glycolysis.
 

WheatLom

2+ Year Member
Jul 6, 2016
710
554
Status
Pre-Dental
Im getting confused because in the destroyer it says that the first enzymatic activity for digestion occurs in the stomach. However, I'm pretty sure the first enzymatic activity starts in the mouth with salivary amylase.

Another question, so I know glycolysis produces 2 ATP for each glucose molecule so can I say that 1 pyruvate produces 1 ATP and 1 lactate during lactic acid fermentation?

Digestion starts in the mouth. A-amalase (-ase means enzyme) so carbohydrates still begin digestion in the mouth.

This question comes up a lot.

Proteins digest first in the stomach, the acids and peptidases are located in the stomach, and small intestine.


So yes. You are right, enzymatic digestion begins in the mouth.



Glycolysis actually forms 4 ATP, however 2 ATP are used in the breakdown of glucose to pyruvate. Therefore the overall net gain is 2 ATP. You should be aware of the difference. Usually you will be asked the net gain, but there is a total 4 produced, with 2 used.
 
OP
bballjake300

bballjake300

2+ Year Member
Jul 11, 2016
30
13
Status
Pre-Dental
Digestion starts in the mouth. A-amalase (-ase means enzyme) so carbohydrates still begin digestion in the mouth.

This question comes up a lot.

Proteins digest first in the stomach, the acids and peptidases are located in the stomach, and small intestine.


So yes. You are right, enzymatic digestion begins in the mouth.



Glycolysis actually forms 4 ATP, however 2 ATP are used in the breakdown of glucose to pyruvate. Therefore the overall net gain is 2 ATP. You should be aware of the difference. Usually you will be asked the net gain, but there is a total 4 produced, with 2 used.
Ahhh Thanks! but my main question is does lactic acid fermentation produce ATP? and if so is it 1 ATP per pyruvate?
 

WheatLom

2+ Year Member
Jul 6, 2016
710
554
Status
Pre-Dental
Ahhh Thanks! but my main question is does lactic acid fermentation produce ATP? and if so is it 1 ATP per pyruvate?
Yes it does produce 1 ATP per pyruvate 2 per glucose. However the main goal of lactic acid fermentation is to regenerate Nad+, the energy in lactic acid fermation comes from Nadh produced during glycolysis. The nad+ that is regenerated can now be apart of glycolysis again. If aerobic conditions are present you go to the Krebs cycle and oxidative phosphorylation
 
  • Like
Reactions: bballjake300

Cranjis McBasketball

SDN Bronze Donor
Bronze Donor
2+ Year Member
Jul 20, 2015
1,384
1,681
Status
Medical Student
Yes it does produce 1 ATP per pyruvate 2 per glucose. However the main goal of lactic acid fermentation is to regenerate Nad+, the energy in lactic acid fermation comes from Nadh produced during glycolysis. The nad+ that is regenerated can now be apart of glycolysis again. If aerobic conditions are present you go to the Krebs cycle and oxidative phosphorylation
No.. If its talking specifically about lactic acid fermentation then ATP is not a product. ATP is produced because the NAD+ (products of lactic acid fermentation) go through glycolysis again. Lactic Acid Fermentation itself doesnt make atp


Sent from my iPhone using SDN mobile
 

WheatLom

2+ Year Member
Jul 6, 2016
710
554
Status
Pre-Dental
No.. If its talking specifically about lactic acid fermentation then ATP is not a product. ATP is produced because the NAD+ (products of lactic acid fermentation) go through glycolysis again. Lactic Acid Fermentation itself doesnt make atp


Sent from my iPhone using SDN mobile
You stand corrected. ATP only is glycolysis. However the energy in lactic acid fermentation does come from Nadh
 

fit2

2+ Year Member
Aug 7, 2015
1,090
785
Status
Pre-Dental
I have a question too about it. Where does lipid digestion start? Is it in mouth as well? I can't remember from my anatomy class last year but didn't the tongue secrete some enzyme? Thanks for clarifying
 
OP
bballjake300

bballjake300

2+ Year Member
Jul 11, 2016
30
13
Status
Pre-Dental
Yes it does produce 1 ATP per pyruvate 2 per glucose. However the main goal of lactic acid fermentation is to regenerate Nad+, the energy in lactic acid fermation comes from Nadh produced during glycolysis. The nad+ that is regenerated can now be apart of glycolysis again. If aerobic conditions are present you go to the Krebs cycle and oxidative phosphorylation
Wow thank you so much! There's just one more thing if you can clarify.. what's the differe
I have a question too about it. Where does lipid digestion start? Is it in mouth as well? I can't remember from my anatomy class last year but didn't the tongue secrete some enzyme? Thanks for clarifying
I think all enzymatic digestion first occurs in the mouth but I'm not completely sure
 

fit2

2+ Year Member
Aug 7, 2015
1,090
785
Status
Pre-Dental
Wait but not protein until it gets to the stomach right? Cause pepsin is the first enzyme that cleaves peptides.
 

WheatLom

2+ Year Member
Jul 6, 2016
710
554
Status
Pre-Dental
Wow thank you so much! There's just one more thing if you can clarify.. what's the differe

I think all enzymatic digestion first occurs in the mouth but I'm not completely sure


Difference in aerobic vs anerobic?
 

WheatLom

2+ Year Member
Jul 6, 2016
710
554
Status
Pre-Dental
I have a question too about it. Where does lipid digestion start? Is it in mouth as well? I can't remember from my anatomy class last year but didn't the tongue secrete some enzyme? Thanks for clarifying

It starts in the mouth with lingual lipase. A little occurrs in the stomach, but a vast majority is in the small intestine when bile can emulsify the lipids the most.

Proteins are in the stomach I believe.
 
  • Like
Reactions: bballjake300

WheatLom

2+ Year Member
Jul 6, 2016
710
554
Status
Pre-Dental
It starts in the mouth with lingual lipase. A little occurrs in the stomach, but a vast majority is in the small intestine when bile can emulsify the lipids the most.

Remember lipids are absorbed into the lymph system, and then go right into the heart!!

Proteins and carbs go to the liver, (correct me if I am wrong here)

Proteins are in the stomach I believe.
 

Cranjis McBasketball

SDN Bronze Donor
Bronze Donor
2+ Year Member
Jul 20, 2015
1,384
1,681
Status
Medical Student
Difference in aerobic vs anerobic?
Aerobic has oxygen as the last electron acceptor in the electron transport chain. So the NADH are ozidized to NAD+ and start over. However if there is no oxygen (blood cant supply oxygen to muscles fast enough) then there becomes an over supply of NADH and not enough NAD+ so anaerobic is a way to oxidize the NADH and generate more NAD+ without oxygen. Its right after glycolysis (which is also considered anaerobic)


Sent from my iPhone using SDN mobile
 
  • Like
Reactions: orgoman22

WheatLom

2+ Year Member
Jul 6, 2016
710
554
Status
Pre-Dental
Aerobic has oxygen as the last electron acceptor in the electron transport chain. So the NADH are ozidized to NAD+ and start over. However if there is no oxygen (blood cant supply oxygen to muscles fast enough) then there becomes an over supply of NADH and not enough NAD+ so anaerobic is a way to oxidize the NADH and generate more NAD+ without oxygen. Its right after glycolysis (which is also considered anaerobic)


Sent from my iPhone using SDN mobile
Oh I know lol, I didn't know what he was asking