Question

Complete the following chart : 
\[\begin{array}{ll} \textbf{Sr. No.} & \textbf{Proteins} \hspace{2cm} \textbf{Name of the Organs} \\ \text{1.} & \text{Melanin, Keratin \hspace{2.5cm} Skin} \\ \text{2.} & \text{Insulin, Trypsin \hspace{2.5cm} Pancreas} \\ \text{3.} & \text{Haemoglobin, Antibodies \hspace{1.8cm} Blood} \\  \end{array}\]

Hint:

Match each protein to the organ or tissue where it is synthesised or primarily functions: pigments and structural proteins to skin, digestive enzymes and hormones to pancreas, and transport/immune proteins to blood.

Answer 1

1. Melanin, Keratin — Skin. Melanin is the pigment produced by melanocytes in the epidermis that determines skin colour and protects against UV radiation; keratin is a fibrous structural protein of epidermal cells, hair and nails that provides mechanical strength and waterproofing.
2. Insulin, Trypsin — Pancreas. Insulin is a peptide hormone secreted by the pancreatic islets (beta cells) that regulates blood glucose; trypsin is a proteolytic enzyme produced by the pancreas (secreted as trypsinogen) that helps digest proteins in the small intestine.
3. Haemoglobin, Antibodies — Blood. Haemoglobin is the oxygen-carrying protein in red blood cells; antibodies (immunoglobulins) are proteins produced by B lymphocytes circulating in blood and plasma that recognise and neutralise pathogens.