What is the Difference Between Aqueous Humor and Vitreous Humor

The main difference between aqueous humor and vitreous humor is that aqueous humor is the clear fluid occurring in front of the eye, whereas vitreous humor is the clear gel-like substance occurring in the space of the lens and retina of the eye.

Aqueous humor and vitreous humor are two types of bodily fluids occurring in the eye. Generally, both fluids are made up of water and other components that nourish and protect the eye.

Key Areas Covered

1. What is Aqueous Humor
     – Definition, Structure, Function
2. What is Vitreous Humor
     – Definition, Structure, Function
3. Similarities Between Aqueous Humor and Vitreous Humor
     – Outline of Common Features
4. Difference Between Aqueous Humor and Vitreous Humor
     – Comparison of Key Differences

Key Terms

Aqueous Humor, Vitreous Humor

Aqueous Humor vs Vitreous Humor - Comparison Summary

What is Aqueous Humor

Aqueous humor is a water-like fluid occurring in the space of the lens and the cornea. It is a transparent bodily fluid that resembles blood plasma. It contains a low protein concentration. The ciliary body is the part of the eye that secretes the aqueous humor. The main function of aqueous humor is to provide structural support to the lens of the eyeball. Aqueous humor contains amino acids transported from ciliary muscles, 98% of water, electrolytes, ascorbic acids, glutathione, and immunoglobulins.

Compare Aqueous Humor and Vitreous Humor - What's the difference?

Figure 1: The Three Layers of the Eye

Furthermore, the functions of the aqueous humor include the maintenance of intraocular pressure and inflating the globe of the eye, providing nutrition (glucose and amino acids) to the posterior cornea, lens, trabecular meshwork, and anterior vitreous, providing ascorbic acid to the anterior segment to act as an antioxidant, defend against pathogens, refracting light, and preventing dryness of the eye.

What is Vitreous Humor

Vitreous humor is the clear gel filling the space between the lens of the eye and the retina of the eyeball. It is a transparent, clear, gelatinous mass surrounded by a layer of collagen known as a vitreous membrane. Moreover, the vitreous humor takes up to four fifth of the volume of the eyeball. The vitreous humor is fluid-like from its center while jelly-like near the edges. Apart from that, the vitreous humor is more viscous than water. Generally, it contains sugars, salts, proteins, and collagen. In addition to that, it contains phagocytes to keep the eye clean from dust and pathogens.

Aqueous Humor vs Vitreous Humor

Figure 2: Eye Structure

Moreover, the vitreous humor serves as a refractive medium for light. Normally, it keeps the eyeball healthy while controlling its shape and size. The vitreous humor also protects the eye from pathogens.

Similarities Between Aqueous Humor and Vitreous Humor

  • Aqueous humor and vitreous humor are two types of bodily fluids that occur inside the eye.
  • They are jelly-like and mainly made up of water.
  • Their function is to nourish and protect the eye.
  • They bend light and maintain the shape of the eye.

Difference Between Aqueous Humor and Vitreous Humor

Definition

Aqueous humor refers to the clear fluid filling the space in the front of the eyeball between the lens and the cornea, while vitreous humor refers to the transparent gelatinous tissue filling the eyeball behind the lens.

Occurrence

Aqueous humor occurs in front of the eye between the lens and the cornea, while vitreous humor occurs between the lens and the retina.

Thickness

While aqueous humor is an aqueous fluid, vitreous humor is a clear, jelly-like fluid.

Reaction to Light

Aqueous humor serves as a reflecting medium, while vitreous humor serves as a refractive medium.

Movement

The aqueous humor is wet and moves, while the vitreous humor does not move.

Function

In addition, aqueous humor keeps the shape of the eye and provides nutrients to the cornea, while vitreous humor bends light and keeps the shape of the eye.

Conclusion

In brief, aqueous humor and vitreous humor are two types of bodily fluids that occur in the eye. Generally, both are jelly-like fluids, mainly made up of water. Aqueous humor occurs in front of the eyes between the lens and the cornea. The main function of aqueous humor is to keep the shape of the eye while providing nourishment to the cornea. In comparison, vitreous humor is the fluid occurring between the lens and the retina. However, the function of the vitreous humor is to keep the eye shape while bending light. Therefore, the main difference between aqueous humor and vitreous humor is their structure and function.

References:
  1. “Aqueous humor.” American Academy of Ophthalmology. 
  2. “Vitreous humor: What is it, location, function, most …” Osmosis. 
Image Courtesy:
  1. Three Main Layers of the Eye” By Artwork by Holly Fischer – Own work (CC BY 3.0) via Commons Wikimedia
  2. Schematic diagram of the human eye en” By Rhcastilhos. And Jmarchn. – Own Work (CC BY-SA 3.0) via Commons Wikimedia

About the Author: Lakna

Lakna, a graduate in Molecular Biology and Biochemistry, is a Molecular Biologist and has a broad and keen interest in the discovery of nature related things. She has a keen interest in writing articles regarding science.

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