Which of the following is a long continuous strand of DNA that carries genetic information?

Appeared in: JODHPUR AIIMS SNO-2018

Explanation

A chromosome is a rod-shaped structure located in the nucleus of a cell.
It is composed of a single, long molecule of DNA that is tightly coiled around proteins called histones.
This DNA molecule contains the genes, which are the basic units of heredity and carry the instructions for building and maintaining an organism.

Option A: Ribosomes are responsible for protein synthesis. They translate the genetic code from messenger RNA (mRNA) but are not themselves long strands of DNA.
Option B: The nucleus is the organelle that contains the chromosomes. It is the storage compartment for the DNA, not the DNA strand itself.
Option D: Mitochondria are the cell's powerhouses, generating ATP. While they do contain their own small, circular DNA (mtDNA), the question refers to the primary, long strands of DNA that carry the bulk of genetic information, which are the chromosomes in the nucleus.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Structure and Function of Cellular Organelles as background academic context rather than a clinical decision trigger.
Understanding chromosomes is fundamental to genetics and medicine. Abnormalities in chromosome number or structure can lead to various genetic disorders.
For example, Down syndrome (Trisomy 21) is caused by an extra copy of chromosome 21. Turner syndrome is caused by a missing or incomplete X chromosome in females.
Genetic testing, such as karyotyping, analyzes a person's chromosomes to detect these abnormalities, which is crucial for diagnosis and genetic counseling.

How to Approach the Question

This is a factual recall question that tests your knowledge of basic cell biology.
First, identify the key terms in the question: 'long continuous strand of DNA' and 'carries genetic information'.
Next, review each option and recall its primary function within the cell.
Ribosome: protein synthesis.
Nucleus: contains genetic material.
Chromosome: made of DNA, carries genes.

Concept Tested & Keywords

QUjEG2yz09GDQY4KuOBfAO

E6 Physiology Essentials Sembulingam 10e Part 1 pp. 34-36, 35-37

E6 Pharmacology Nursing Lilley 11e Part 1 p. 115-117

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Attempt every question from this paper in a timed mock, then review the full solution for each one.