Before entering into the respiratory pathway,fats break down into:

Common molecule formed from all food stuffs during aerobic respiration is

$A-$ Breaking down processes within the living organism is anabolism and synthesis is catabolism.
$R-$ The proteins would be degraded by proteases and the individual amino acids (after deamination) depending on their structure would enter the pathway at some stage within the Kreb's cycle or even as pyruvate or acetyl $CoA$.

$A-$ Glycolysis involves only catabolic process.
$R-$ Amphibolic pathway involves both catabolic and anabolic processes.

Which of the following links carbohydrate and fat metabolism?

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 $PGAL$.