Question

For four degradation products resulting from the activity of extracellular enzymes (lipases, amylases, maltases, caseinases), identify a degradation product and a nutrient transport mechanism for that product.

Could you please specify which is the degradation product and which one is a nutrient transport?

Answer 1

Lipases are esterases i.e. they cleave ester bond between the glycorol moiety and fatty acid
Triglyceride -------> Diglyceride + Fatty acid
Fatty acids can be transported by two mechanisms.
Since fatty acids hydrophobic in nature, they can passively diffuse across the membrane
The other mechanisms involve protein/carrier-mediated transport into key tissues such as the liver.
Ex: A specific Carnitine transport mechanism transports fatty acyl CoA into the mitochondria.

Amylase is a glycosidase i.e. It cleaves the glycosidic bond between monosaccharides
Since carbohydrates are polar molecules, they cannot freely diffuse across the membrane. They require a specific carrier system for their transport.
Ex: GLUT4 is a carrier molecule for the transport of glucose molecules

Maltase is also a glycosidase. It hydrolyzes Maltose to produce two glucose molecules.

Caseinase is a protease i.e. it cleaves peptide bonds between amino acids
It is a Lysyl endopeptidase. It breaks down casein into several small peptides.
Since peptides are polar molecules, they cannot freely diffuse across the membrane. They require a specific carrier system for their transport.