Find out and make a list of proteins used as therapeutic agents. Find other applications of proteins (e.g.,cosmetics,etc.).

(N/A) Proteins used as therapeutic agents are as follows:
$1$. $Thrombin$ and $Fibrinogen$: These proteins play a crucial role in the blood clotting process.
$2$. $Antibodies$ (Immunoglobulins): These are essential for immune responses and are used in various diagnostic and therapeutic applications.
$3$. $Insulin$: $A$ peptide hormone used to regulate blood glucose levels in patients with diabetes mellitus.
$4$. $Renin$: An enzyme involved in the regulation of blood pressure and osmoregulation.
Other applications of proteins include:
- $Cosmetics$: Proteins like collagen and keratin are widely used in skin and hair care products.
- $Toxins$: Certain proteins act as biological toxins (e.g.,$Botulinum$ toxin) used in medical treatments.
- $Biological$ $Buffers$: Proteins help maintain $pH$ stability in various biochemical processes.