Question

Match the cell organelles given in Column-l with cellular processes in Column- II and select the correct option from the codes given below. Column-I \(\quad\) Column-II A. Lysosomes. (i) Protein synthesis B. Ribosomes (ii) Hydrolytic activity C. Smooth endoplasmic (iii) Steroid synthesis reticulum D. Centriole (iv) Formation of spindle \(\begin{array}{llll}\text { A } & \text { B } C & \text { D }\end{array}\) (a) (ii) (i) (iii) (iv) (b) (i) (iii) (iv) (ii) (c) (i) (iv) (iii) (ii) (d) (iv) (iii) (i) \(\quad\) (ii)

Short answer

The correct match is: A-(ii), B-(i), C-(iii), D-(iv), which corresponds to option (a).

Step-by-step solution

Identify the Lysosomes Function

Match A. Lysosomes with the correct cellular process. Lysosomes are known for their digestive functions within the cell, breaking down waste material and cellular debris. Therefore, they are associated with hydrolytic activity.

Identify the Ribosomes Function

Match B. Ribosomes with the appropriate cellular function. Ribosomes are the site of protein synthesis within the cells, so they would match with protein synthesis.

Identify the Smooth Endoplasmic Reticulum Function

Match C. Smooth endoplasmic reticulum with its cellular process. The smooth endoplasmic reticulum is involved in various metabolic processes, including the synthesis of lipids, such as steroids. Therefore, it matches with steroid synthesis.

Identify the Centriole Function

Match D. Centriole with the correct cellular process. Centrioles are involved in cell division and are known to assist in the formation of the spindle apparatus during mitosis. Hence, centrioles match with the formation of spindle fibers.

Combining all Matches to Determine the Correct Option

Combine all matches to find the correct sequence: A associates with (ii) Hydrolytic activity, B with (i) Protein synthesis, C with (iii) Steroid synthesis, and D with (iv) Formation of spindle. The correct option with these matches would be the one that aligns with these associations.

Key concepts

Lysosomes and Hydrolytic Activity

Lysosomes are often referred to as the 'stomach' of the cell, but they are much more than simple digestive organs. These tiny, membrane-bound organelles contain a variety of enzymes capable of breaking down all types of biological polymers—proteins, nucleic acids, carbohydrates, and lipids. These enzymes are highly active at the acidic pH found within lysosomes, thus enabling the organelle's hydrolytic activity.

Lysosomes perform crucial functions, such as degrading waste material and cellular debris. They can even break down complex macromolecules and recycle worn-out cellular structures, a process vital for cell maintenance and renewal. Understanding lysosome function is not only essential for comprehending cellular recycling processes, but also for recognizing their role in diseases, where their dysfunction may lead to pathological conditions.

Ribosomes and Protein Synthesis

Ribosomes are the cellular 'factories' where the synthesis of proteins occurs. These small, complex structures can be found floating freely within the cytoplasm or attached to the rough endoplasmic reticulum. They consist of RNA and proteins and are the site where the translation of messenger RNA (mRNA) into the amino acid sequences of proteins takes place.

During protein synthesis, ribosomes read the sequence of the mRNA and, using transfer RNA (tRNA) molecules, they add the corresponding amino acids one by one to elongate the growing protein chain. This process, known as translation, is fundamental to all cellular activities because proteins play a role in virtually all biological functions. When learning about ribosomes, one truly grasps the central dogma of molecular biology: DNA→RNA→Protein.

Smooth Endoplasmic Reticulum and Steroid Synthesis

The smooth endoplasmic reticulum (SER) is a maze-like organelle that plays an integral role in synthesizing lipids, including important molecules like steroids. Steroids are a class of lipids commonly known for their role as hormones, which regulate various physiological processes.

The SER provides a specialized platform for the production of lipids by hosting the enzymes necessary for these complex biochemical reactions. In cells that produce large amounts of steroids, such as those in the adrenal glands and gonads, the SER is particularly abundant. The production of steroid hormones is a multi-step process requiring precise enzymatic activity, which is one reason why the role of the SER in cell physiology is so significant. The study of SER function is essential for understanding various aspects of cell metabolism, including how lipids are made and processed.

Centrioles and Spindle Formation

Centrioles are cylindrical structures that play a key role in cell division, specifically in the process of mitosis and meiosis. Their main function is to assist in the formation of the spindle fibers that separate chromosomes during cell division.

During the process, a pair of centrioles moves to opposite ends of the cell, where they serve as anchor points for the spindle fibers. This spindle apparatus ensures that chromosomes are divided evenly between the two new daughter cells. Understanding the function of centrioles is crucial for understanding the mechanisms behind cell reproduction and the faithful transmission of genetic information from one generation to the next. Studying the role of centrioles also sheds light on the intricate choreography of cell division and the ways in which errors in this process can lead to abnormalities such as cancer.