Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
To ensure efficient gas exchange in a large, thick-tissued artificial organism, which system must the scientist implement?
Direct diffusion across the skin
A complex circulatory system with respiratory pigments
Increased surface area of the external membrane
A system of tracheal tubes only
A complex circulatory system with respiratory pigments
In large organisms with thick tissues, the diffusion distance becomes too large for gases to reach internal cells effectively, rendering direct diffusion insufficient. A circulatory system combined with respiratory pigments like hemoglobin facilitates the rapid transport and increased solubility of oxygen, ensuring all cells receive adequate gas exchange.
In large organisms with thick tissues, the diffusion distance becomes too large for gases to reach internal cells effectively, rendering direct diffusion insufficient. A circulatory system combined with respiratory pigments like hemoglobin facilitates the rapid transport and increased solubility of oxygen, ensuring all cells receive adequate gas exchange.
Think of direct diffusion as trying to water a giant lawn using a tiny mist sprayer (only the edges get wet), while a circulatory system is like installing a network of garden hoses to reach every single plant in the middle of the field.
J=тИТDdxdcтАЛ тАФ Fick's first law of diffusion describing flux (J) across a concentration gradient (dc/dx)
Hb+4O2тАЛтЗМHb(O2тАЛ)4тАЛ тАФ Reversible binding of oxygen to hemoglobin
The principle relies on Fick's Law of Diffusion, which states that the rate of diffusion is inversely proportional to the thickness of the membrane (rateтИЭthickness1тАЛ). Respiratory pigments increase the oxygen-carrying capacity of blood by orders of magnitude compared to simple physical dissolution, allowing oxygen to be 'packed' and delivered to deep tissues far from the gas exchange surface.
Diffusion is only efficient over distances of less than 1 mm.
Respiratory pigments overcome the low solubility of oxygen in aqueous plasma.
Thick tissues necessitate bulk transport systems (circulatory system) to bypass the limitations of passive diffusion.
Efficient support for high metabolic rates
Allows for larger body sizes and complex tissue organization
Maintains constant internal environment homeostasis
Requires high energy investment for pumping heart
Vulnerable to system-wide failures
Human circulatory system
Advanced synthetic bio-engineering designs
| Feature | Direct Diffusion | Circulatory System |
|---|---|---|
Efficiency in Thick Tissue | Inadequate (Passive limitation) | Highly Effective (Active transport) |
Oxygen diffusion in water is approximately 10,000 times slower than in air.
Option A is ineffective because the surface-area-to-volume ratio decreases as an organism grows.
Option C provides surface area but fails to transport molecules deep into thick solid tissues.
Option D (Tracheal system) is limited to small insects due to the passive nature of air flow through tubes.
B is correct тАФ A complex circulatory system with respiratory pigments overcomes the physical limitations of slow passive diffusion in thick-tissued organisms.
Always remember that biological systems face physical constraints; small organisms use physics (diffusion) while large organisms must use engineering (bulk flow/circulatory systems).
Get instant step-by-step AI explanations, full shift Previous Year Papers (SSC GD, RRB, SSC JE), and regional rank analysis on the official Examoogle App.
Free Download тАв 100K+ Aspirants