Question

Which organelle helps in the synthesis of lipids, cholesterol, steroids and visual pigments in epithelial cells of retina? (a) golgi bodies (b) RER (c) SER (d) Mitochondria

Short answer

The organelle that helps in the synthesis of lipids, cholesterol, steroids, and visual pigments in epithelial cells of retina is (c) SER.

Step-by-step solution

Identify the Function

The question asks about the organelle responsible for the synthesis of lipids, cholesterol, steroids, and visual pigments. Each organelle in a cell has specific functions.

Rule Out Irrelevant Options

Golgi bodies are involved in modifying, sorting, and packaging proteins and lipids for secretion or for use within the cell. Mitochondria are the powerhouses of the cell, generating ATP. RER, or rough endoplasmic reticulum, is involved in protein synthesis.

Identify the Correct Organelle

SER, or smooth endoplasmic reticulum, has functions that include the synthesis of lipids, cholesterol, and steroids. It is also involved in the production of hormones and detoxification. In the retina, SER helps in the synthesis of visual pigments.

Key concepts

Smooth Endoplasmic Reticulum

The smooth endoplasmic reticulum (SER) plays a vital role in cellular function, particularly in the synthesis of various molecules. Unlike its counterpart, the rough ER, which is dotted with ribosomes, the SER has a smooth appearance under a microscope. It is in the SER where the cell assembles important lipids such as cholesterol and phospholipids. These are crucial for creating and maintaining cell membranes.

Further, the SER is responsible for the synthesis of steroid hormones, which are derived from cholesterol. These hormones are then involved in regulating various physiological processes. In addition, the SER detoxifies chemicals and metabolizes carbohydrates. Within ocular cells, such as those in the retina, the SER is essential for producing visual pigments that enable us to process light and thus, help us to see.

Synthesis of Lipids

The synthesis of lipids is a fundamental process within cells, essential for life. Lipids are a diverse group of molecules with a variety of functions, such as providing energy storage and forming the structural components of cell membranes. The smooth endoplasmic reticulum is the site where many lipids are synthesized. Here, enzymes assist in the creation of fatty acids and phospholipids. Additionally, triglycerides and cholesterol, both significant types of lipids, are also synthesized in the SER.

Lipids are also important for creating signaling molecules and can influence cellular communication. These processes are tightly regulated within the cell to ensure balance and proper function. An imbalance in lipid synthesis can lead to diseases such as lipidosis or atherosclerosis, highlighting the critical nature of this cellular activity.

Biology Cell Structure

Understanding cell structure is fundamental to comprehending how life functions at the most basic level. The cell is the basic unit of life and is made up of various organelles, each with specific roles. The outer boundary of the cell, the plasma membrane, is composed of a lipid bilayer embedded with proteins, which controls the entry and exit of substances.

Within the cell, organelles like mitochondria, Golgi apparatus, and endoplasmic reticulum are critical for energy production, protein processing, and lipid synthesis, respectively. The nucleus serves as the control center, harboring DNA. These components work in unison to maintain cellular health and function. The collaboration of organelles within the complex cell structure allows for remarkable biological processes, from respiration to reproduction.