Q. 12 - Biology

Question

The presence of a membrane-enclosed nucleus is a

characteristic of ________.

a. prokaryotic cells

b. eukaryotic cells

c. living organisms

d. bacteria

Step-by-Step Solution

Answer

The presence of a membrane-enclosed nucleus is a

characteristic of eukaryotic cells.

Step 1: Introduction

An eukaryotic cell can be either single-celled or multicellular in plants, animals, fungi and as well as algae.

Step 2: Explanation Incorrect answer (a), (c) and (d)

The spindle could be a surface a part of the cell that holds the mitochondrial dna of cells.

Prokaryotes are single-celled organisms which lack mitochondria, a membrane bound nucleus, and the other organelle that's membrane bound. All living organisms don't contain a membrane enclosed nucleus. Bacteria are prokaryotes and are enucleated. 

Step 3: Explanation Correct answer (b)

The name “Eukaryotic” means Eu – true, karyon – nucleus.

Eukaryotic cells have plasma membrane which encloses a nucleus and other organelles.

Eukaryotic cells are large and complex in structure. 

The primary components of eukaryotic cells were nucleus, nucleolus, plasma membrane, cell wall, ribosomes, mitochondria, cytoplasm, cytosol, endoplasmic reticulum, vesicles and vacuoles.

Protein synthesis occurs in cellular structures called ribosomes, found out-side the nucleus. 

Some examples of eukaryotes are Animals, plants, fungi, protozoans and algae.