Human Physiology Lecture Notes

Artery vs Vein: Similarities and Differences (A Comparison Table)

difference between artery and vein

Arteries vs Veins
Similarities and Differences between Arteries and Veins

The circulatory system in an organism ensures the transport of oxygen, nutrients, carbon dioxide and hormone throughout the body. The blood circulatory system in an animal is facilitated by the heart (the blood pumping organ) and blood vessels (closed pipelines which carry out the circulation of blood throughout the body). There are three types of blood vessels in our body. They are:

(1).    Arteries
(2).    Veins
(3).    Capillaries

(1). Artery: They are blood vessels which originated from the heart and carry blood away from the heart. Arteries usually carry oxygenated blood except for pulmonary and umbilical arteries that carries deoxygenated blood.

(2). Vein: They are blood vessels which carry blood to the heart from various organs of the body. Veins usually carry deoxygenated blood except for pulmonary and umbilical vein that carries oxygenated blood.

(3). Capillaries: They are minutes blood vessels of one cell layer thickness and they facilitate the exchange of oxygen, carbon dioxide, nutrients and hormones in the blood to individuals cells of different organs. Arteries and veins are interconnected through capillaries and thus the blood circulation forms a closed system in majority of animals.

The current post describes the similarities and differences between Arteries and Veins with a comparison table.

Similarities between Arteries and Veins

Ø  Both are blood vessels.

Ø  Both transport blood.

Ø  Blood transport is unidirectional in both arteries and vein.

Ø  Arteries and veins composed of layers of cells.

Ø  Both arteries and veins composed of three layers of cells namely Tunica externa (external layer), tunica media (middle layer) and tunica interna (internal layer).

Ø  Both arteries and veins are covered by muscular tissues which assist in the contraction or expansion of blood vessels.

Ø  Both undergo vasoconstriction and vasodilation to adjust the blood pressure according to the action of hormones and neurotransmitters.

Ø  Both arteries and veins show anastomosis.

Difference between Arteries and Veins

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Zoology lecture notes and study materials

Classification of Arthropoda with Identification Characters for Each Sub-Phylum and Class

How Arthropods further classified


Arthropods are classified into five sub-phylum and each then subdivide into classes (a total of 16 classes according to recent classification of animal taxa).

Phylum Arthropoda:

I.   Sub-phylum: Trilobitomorpha (extinct arthropods)

Class 1: Trilobita

II.   Sub-phylum: Chelicerata (spiders, horseshoe crabs)

Class 1: Arachnida
Class 2: Merostomata
Class 3: Pycnogonida

III.  Sub-phylum: Myriapoda (centipedes, millipedes)

Class 1: Chilopoda
Class 2: Diplopoda
Class 3: Pauropoda
Class 4: Symphyla

IV.  Sub-phylum: Crustaceae (crabs, prawns, shrimps)

Class 1: Branchiopoda
Class 2: Remipedia
Class 3: Cephalocarida
Class 4: Maxillopoda
Class 5: Ostracoda
Class 6: Malacostraca

V.   Sub-phylum: Hexapoda (insects)

Class 1: Insecta
Class 2: Entognatha

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