Protein metabolism and ATP synthesis

How is dietary protein digested?

In the stomach, hydrochloric acid and proteases break down proteins into smaller chains of amino acids. In the small intestine, the pancreas releases enzymes that further break down the amino acid chains into individual amino acids.

How is dietary protein absorbed?

In the small intestine, enterocytes absorb the resulting mixture of free amino acids and small peptides.

Name the metabolic pathways that are involved when amino acids are used as a source of chemical energy.  

Deamination which is a process that removes an amino group from a molecule.

How is the ammonium ion removed from the body?

The body removes ammonium ions from the body by converting ammonia into urea and excreting it in urine.

Why is ammonia toxic?

it reacts with water in the body to form ammonium hydroxide, this is highly toxic and can be life threatening

Why is it possible that a high concentration of ammonium ions may reduce physical performance?

Ammonia can cause muscle fatigue by lowering adenosine triphosphate content in muscle cells. This can happen during exercise when plasma ammonia concentrations reach levels similar to those found in patients with liver disease.

Which organs are involved in the detoxification and excretion of ammonium ions? 

the liver turns tthe ammonia into urea and the kindneys turn the urea into urine to be excreted

In which metabolic situations are amino acids broken down? 

energy production, stavation and excess amino acids

Why are amino acids broken down during starvation? 

Amino acids are broken down during starvation to provide an alternative energy source and fuel body functions

What is gluconeogenesis?

Gluconeogenesis is the process by which the body creates glucose from non-sugar precursors, such as amino acids, lactate, and glycerol