Iron deficiency is a common problem in humans worldwide. The homeostasis of iron in the body is maintained using various proteins (column‐ X) and their function (column‐ Y): Column X Column Y A. Ferritin i. B. ii. C. iii. D. iv.Hypoxia is known to reduce its synthesis Ferroportin Plasma iron binding protein Transferrin Intramucosal cell iron binding protein Hepcidin Iron leaves mucosal cells through it
Choose the correct option from below that most appropriately matches in column X with that of column Y.
A - iii, B - iv, C - ii, D - i
Iron Homeostasis Proteins and Functions
Iron is an essential mineral, and maintaining its balance (homeostasis) in the human body is crucial for health. This balance is managed by various proteins, each with a specific role in iron absorption, transport, storage, and regulation. Understanding these proteins and their functions is key to understanding iron metabolism.
Matching Iron Proteins to Functions
Let's examine the proteins listed in Column X and their corresponding functions in Column Y to find the correct matches:
- Ferritin: This protein is the primary iron storage protein found inside cells, particularly in the liver and bone marrow. It binds iron within the cell, preventing it from becoming toxic. This function aligns with "Intramucosal cell iron binding protein" (iii). Therefore, A – iii.
- Ferroportin: This is the only known cellular iron exporter protein. It is found on the surface of cells that release iron into the bloodstream, such as intestinal enterocytes, macrophages, and hepatocytes. Iron leaves mucosal cells and enters circulation through Ferroportin. This matches "Iron leaves mucosal cells through it" (iv). Therefore, B – iv.
- Transferrin: This is a protein found in the blood plasma that binds and transports iron throughout the body. Iron is released from cells (via Ferroportin) and picked up by Transferrin for delivery to tissues that need it, like the bone marrow for red blood cell production. This corresponds to "Plasma iron binding protein" (ii). Therefore, C – ii.
- Hepcidin: This is a hormone produced by the liver that acts as the master regulator of systemic iron metabolism. It primarily controls iron release from cells by binding to Ferroportin and causing its degradation. Hepcidin synthesis is regulated by the body's iron stores and inflammation. Interestingly, conditions like hypoxia (low oxygen levels) are known to suppress (reduce the synthesis of) Hepcidin, which helps increase iron availability for red blood cell production. This fits with "Hypoxia is known to reduce its synthesis" (i). Therefore, D – i.
Summary of Matches
Based on the functions, the correct matches are:
| Column X (Protein) | Column Y (Function) |
|---|---|
| A. Ferritin | iii. Intramucosal cell iron binding protein |
| B. Ferroportin | iv. Iron leaves mucosal cells through it |
| C. Transferrin | ii. Plasma iron binding protein |
| D. Hepcidin | i. Hypoxia is known to reduce its synthesis |
Comparing these matches with the given options, the option that correctly lists these pairings is the second option.
Important Questions from Cellular communication
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Column X
Column Y
A.
Anchoring junction
i.
Claudins
B.
Occluding junction
ii.
Delta-Notch
C.
Channel-forming junction
iii.
Desmoglein
D.
Signal-relaying junction
iv.
Connexin
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A. Some bacteria express a protein called invasin that is recognized by host-cell β1 integrins.
B. Actin polymerization along with assembly of clathrin coat results in the internalization of bacteria by zipper mechanism.
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D. Some bacteria attach to host cell surface receptors inducing local elevation of Ca2+ in cell cytosol, leading to the fusion of lysosomes with bacteria containing plasma membrane vesicles.
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