Molecular Biology Tutorials

Similarities and Difference between RNA and DNA- A Comparison Table


difference-between-rna-and-dna

Similarities & Differences between DNA and RNA – A Comparison Table

We wish to suggest a structure for the salt of deoxyribose nucleic acid (DNA).
This structure has novel features which are of considerable biological interest.
Watson & Crick, 1953

DNA and RNA are the two types of nucleic acids (a class of macromolecules in the cells) present in all prokaryotic and eukaryotic organisms. Both are essentially the polymers of nucleotides and have immense role in the storage and expression of genetic information in an organism. DNA and RNA allow the storage of genetic information for long period of time without any changes in the genetic constitution of the organism. The presence of two categories of nucleotides also allows the decoding of genetic information during protein synthesis by the process of transcription and translation. The current post describes the similarities and differences between DNA (deoxyribonucleic acid) and RNA (ribonucleic acid).

Similarities between DNA and RNA

Ø  Both DNA and RNA can acts as genetic material.

Ø  Both are polymers of nucleotides.

Ø  Both DNA and RNA are linear structures with secondary and super-secondary arrangements.

Ø  Both contain purines and pyrimidines.

Ø  Both DNA and RNA contain pentose sugar.

Ø  In DNA and RNA the adjacent nucleotides are connected by 3’-5’ phosphodiester bonds.

Ø  Both DNA and RNA absorb UV light at 260 nm.

Ø Both DNA and RNA contain hydrogen bonds

Difference between DNA and RNA

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Human Physiology Lecture Notes

Difference between Sympathetic and Parasympathetic Nervous Systems


difference between parasympathetic and sympathetic nervous system

Sympathetic vs Parasympathetic Nervous Systems
(Similarities and Differences between Sympathetic and Parasympathetic Nervous Systems)

The involuntary or reflex functions in the body are controlled by a part of peripheral nervous system called Autonomous Nervous System (ANS). ANS regulate the functions of internal organs (visceral functions) particularly the functions of heart, stomach and intestine.  The Autonomic Nervous System composed of two components:

            (1). Sympathetic Nervous System (SNS)

           (2). Parasympathetic Nervous System (PNS or PSNS)

Sympathetic Nervous System (SNS): They are the part of ANS which originate from the spinal cord of the thoracic and lumbar region. They control the ‘fight-or-flight’ response or the ‘sympatho-adrenal response’ in the body. SNS prime the body for acting in threatening situations for survival. The sympathetic nervous system acts in the body as complementary to the action of Parasympathetic Nervous System.

Parasympathetic Nervous System (PNS or PSNS): Part of ANS originates from the spinal cord and medulla which control the ‘rest-and-digest’ or ‘feed-and-breed’ activities in the body. They act in the body as complementary to the action of SNS.

The present post describes the similarities and differences between Sympathetic Nervous System and Parasympathetic Nervous System

Similarities between Sympathetic and Parasympathetic Nervous System

Ø  Both are the part of ANS.

Ø  Both originate from the spinal cord.

Ø  Both have huge influence on physiological process of the body such as respiration, circulation, digestion, urination and reproduction.

Ø  Both have role in maintaining the homoeostasis of the body.

Ø  Both composed of pre-ganglionic and post-ganglionic neurons.

Difference between Sympathetic and Parasympathetic Nervous System

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