Hydrolysis Lab Review

What is the difference between an endoenzyme and exoenzyme?

Endoenzyme: Works inside the cell.

Exoenzyme: Secreted outside the cell to break down large molecules so they can be absorbed.

Endoenzyme:

Works inside the cell.

Secreted outside the cell to break down large molecules so they can be absorbed.

Exoenzyme

Amylase substrate

Starch

Amylase products

Maltose and glucose units

Indicator for amylase test

Iodine

Media for amylase test

Starch agar

Positive amylase result

Clear zone around growth after iodine

Negative amylase result

Blue‑black color around growth

Lipase substrate

Triglycerides

Lipase products

Glycerol and fatty acids

Media for lipase test

Spirit Blue Agar

Positive lipase result

Dark blue halo around growth

Negative lipase result

No blue halo

Gelatinase substrate

Gelatin

Gelatinase products

Amino acids and polypeptides

Media for gelatinase test

Nutrient gelatin deep

Purpose of ice bath in gelatinase test

Checks if medium solidifies to confirm hydrolysis

Positive gelatinase results

Medium remains liquid after ice bath

Negative gelatinase result

Medium solidifies after ice bath

Urease reaction products

Ammonia and carbon dioxide

Media for urease test

Urea broth

Function of phenol red

pH indicator

Positive urease result

Hot pink color

Negative urease result

Yellow or peach color

is this Positive or Negative in Amylase (Hydrolysis of Starch

positive

is this Positive or Negative in Amylase (Hydrolysis of Starch

negative

is this positive or negative Lipase (Hydrolysis of Lipids)

positive

is this positive or negative Lipase (Hydrolysis of Lipids)

negative

is this positive or negative Gelatinase (Hydrolysis of Gelatin

negative

is this positive or negative Gelatinase (Hydrolysis of Gelatin

positive

is this positive or negatvie Urease (Hydrolysis of Urea

positive

is this positive or negatvie Urease (Hydrolysis of Urea

negative