i) - Red blood cells have respiratory pigment for transport of oxygen.
- Have biconcave shape to increase surface area for diffusion of respiratory gases (oxygen and carbon (IV) oxide; )
- Are pliable to be able to squeeze within narrow blood capillaries.
- Lack nucleus and some other organelles for packaging of more haemoglobin;
- Have thin epithelium for easy diffusion of respiratory gases;
- Are many per unit volume for transport of more oxygen;
- Have enzyme carbonic anhydrase which speeds loading and offloading of carbon (IV) oxide.
- Have a relatively long life span for efficient transport of oxygen;
ii) White blood cells.
- Have nucleus to regulate cell activities as they destroy pathogens;
- Are able to change shape to be able to engulf and destroy pathogens; / are phagocytic to destroy pathogens;
- Are produced in small numbers to prevent them from destroying other cells;
- Produce opsonins / lysins /antitoxins / agglutinins which destroy pathogens / microbes
sharon kalunda answered the question on May 23, 2019 at 13:24
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