If protein enters into the amphibolic pathway,the amino acid is converted into........

Choose the incorrect sentence$(s)$ regarding the amphibolic pathway.
$(1)$ Carbohydrates are generally used as substrates for respiration.
$(2)$ Fatty acids can first be degraded into acetyl $CoA$,which enters the respiratory pathway.
$(3)$ In the case of proteins,they are first broken down into amino acids,which are later converted into pyruvic acid and enter the respiratory pathway.
$(4)$ The respiratory pathway is involved in both anabolism and catabolism.
$(5)$ Glycerol would enter the pathway after being converted to $PGAL$.

Describe the metabolic processes of the respiratory pathway.

Which of the metabolites is common to respiration mediated breakdown of fats,carbohydrates and proteins?

To enter into the respiratory pathway,protein molecules must be converted into:

The $Cori$ cycle is not found in muscles required for contraction at a slow pace and for a prolonged duration. Which organs does the $Cori$ cycle involve?