Problem 18 - Objective Biology for NEET

Question

The cell containing membrane bound nucleus can be called (a) Eukaryotic (b) Prokaryotic (c) Both (a) and (b) (d) None of these

Step-by-Step Solution

Answer

The cell with a membrane bound nucleus is a Eukaryotic cell.

Step 1: Identifying the characteristics of a Eukaryote

First, it must be identify what a Eukaryote is. A Eukaryote is any organism whose cells contain a nucleus and other organelles enclosed within membranes. These types of organisms include plants, animals, and fungi.

Step 2: Identifying the characteristics of a Prokaryote

Next, it must be understand what a Prokaryote is. Prokaryotes are unicellular organisms that lack organelles or other internal membrane-bound structures. Prokaryotes do not have a nucleus, rather they have a nucleoid which is the area within the cell where the genetic material is localized.

Step 3: Making the comparison

Given the characteristics defined in step 1 and 2, one can see that the cell with a membrane-bound nucleus can not be a Prokaryote since they lack a defined nucleus. The cell is therefore a Eukaryote which have a nucleus enclosed within membranes.

Key Concepts

Prokaryotic Cells

Prokaryotic cells are fascinating organisms that differ significantly from eukaryotic cells. They are primarily unicellular, which means they consist of only one cell. One of the key characteristics of prokaryotic cells is that they lack membrane-bound organelles. This means that all their internal components are not separated by membranes, giving these cells a simpler structure.
The genetic material in prokaryotic cells is not enclosed within a nucleus. Instead, it is located in a region called the nucleoid. This makes prokaryotic cells distinct, as their DNA floats freely within the cell.
Common examples of prokaryotic organisms include bacteria and archaea. These organisms are known for being incredibly adaptable, allowing them to thrive in a wide range of environments.

• Unicellular organisms
• Lack membrane-bound organelles
• DNA located in a nucleoid
• Examples: Bacteria and Archaea

Nucleus

The nucleus is often considered the command center of eukaryotic cells. It is a membrane-bound organelle that houses the cell's genetic material in the form of DNA and plays a crucial role in controlling the cell's growth and reproduction. The nucleus is surrounded by a double membrane called the nuclear envelope, which protects the DNA inside.
Within the nucleus, there are structures called chromosomes, which are made up of DNA and proteins. These structures are crucial as they carry all the genetic information necessary for the functioning and reproduction of the cell.
Another important component located inside the nucleus is the nucleolus. The nucleolus is where ribosomal RNA is produced, which is essential for protein synthesis.

• Membrane-bound organelle
• Houses DNA in chromosomes
• Surrounded by nuclear envelope
• Contains nucleolus for rRNA production

Cell Organelles

Eukaryotic cells are distinct because of the presence of various organelles, each with a specific function. These organelles are enclosed within membranes, allowing the cell to perform complex tasks efficiently.
Some of the well-known organelles include the mitochondria, often referred to as the powerhouse of the cell. The mitochondria are responsible for producing energy through the process of cellular respiration. Another key organelle is the endoplasmic reticulum (ER), which comes in two forms: rough ER (covered with ribosomes, involved in protein synthesis) and smooth ER (involved in lipid synthesis and detoxification processes).
The Golgi apparatus is like the cell's packaging and distribution center, modifying and sorting proteins and lipids for transport to different parts of the cell or even outside the cell. Additionally, lysosomes contain digestive enzymes crucial for breaking down waste materials and cellular debris.

• Mitochondria: Energy production
• Endoplasmic Reticulum: Protein and lipid synthesis
• Golgi Apparatus: Modifying and packaging proteins
• Lysosomes: Breakdown of waste