Question

Read the given statements. (i) Flat membranous sacs in stroma of chloroplass (ii) Infoldings in mitochondria (iii) Disc shaped sacs in Golgi apparatus Select the correct option as per the codes given abok Cristae \(\quad\) Cisternae \(\quad\) Thylakoids (a) (iii) (i) (ii) (b) \((i)\) (ii) (iii) (ii) (iii) (i) (d) (iii) (ii) (i)

Short answer

(b) Thylakoids - (i), Cristae - (ii), Cisternae - (iii)

Step-by-step solution

Identify Cellular Structures

First, identify each cellular structure mentioned in the statements. (i) refers to a component found in chloroplasts, (ii) refers to a component in mitochondria, and (iii) refers to a component of the Golgi apparatus.

Match Terminology with Structure

Next, match each term (Thylakoids, Cristae, Cisternae) to the correct cellular structure. Thylakoids are flat membranous sacs found in the stroma of chloroplasts, Cristae are the infoldings found in mitochondria, and Cisternae are the disc-shaped sacs in the Golgi apparatus.

Select the Correct Option

Finally, choose the option that correctly matches each term with the corresponding cellular structure from the statements. Thylakoids correspond to (i), Cristae to (ii), and Cisternae to (iii).

Key concepts

Thylakoids in Chloroplasts

Chloroplasts are the kitchen of plant cells, where the magic of photosynthesis occurs. At the core of this process are structures called thylakoids, which are like flat, coin-like discs stacked on top of each other in the chloroplast stroma. They create units called grana (singular: granum). Each thylakoid houses chlorophyll, the green pigment crucial for capturing light energy.

Think of thylakoids as solar panels, capturing sunlight and converting it into chemical energy during the light-dependent reactions of photosynthesis. This energy is later used to synthesize glucose from carbon dioxide and water, essentially storing solar power as sugar for the plant to use. The thylakoids' surface area is crucial, providing ample space for the necessary reactions and electron transport to occur. This ingenious design is a fine example of nature's optimization strategies.

Cristae in Mitochondria

Mitochondria, often referred to as the powerhouse of the cell, harbor intricate structures known as cristae. These are the inner membrane's folds jutting into the mitochondrial matrix. This convoluted layout serves a critical purpose: it drastically increases the surface area inside mitochondria, where key reactions of cellular respiration take place.

On the cristae, enzymes and electron carriers orchestrate the production of ATP (adenosine triphosphate), the cell's energy currency, through the process of oxidative phosphorylation. The intricate design of cristae allows for an efficient flow of electrons along the electron transport chain, while providing the required space for proteins and enzyme complexes to perform their roles in energy extraction.

Cisternae in Golgi Apparatus

Imagine a bustling post office in the cell, and you have the Golgi apparatus, which processes, sorts, and ships proteins and lipids to their appropriate destinations. Integral to its form and function are the cisternae, which are a series of flattened, stacked pouches where the sorting and modification of cellular products occur.

Each cisterna is like a checkpoint or assembly line, where products are modified, tagged, and packaged into vesicles for transport. These modifications may include glycosylation, the addition of sugars to proteins, which is often vital for their function. The organization of cisternae facilitates a directional flow of cargo, allowing the Golgi apparatus to efficiently manage the cell's logistics with precision.