Quite simple really.... The CNS actually doesn't receive as much nutrients or key components from the blood... The blood actually dumps it into the Cerebrospinal fluid. The Cerebrospinal fluid therefore is directly in contact with the brain and if you want to find an infection you take from a source as close to thing as you can.
Answer:
Birds do not have a diaphragm; instead, air is moved in and out of the respiratory system through pressure changes in the air sacs. ... Bird lungs do not expand or contract like the lungs of mammals. In mammalian lungs, the exchange of oxygen and carbon dioxide occurs in microscopic sacs in the lungs, called 'alveoli.
Explanation:
Answer:
Deep zone, surface zone and transition zone.
Explanation:
Open sea zone is the area of the coastal areas above the sea bed and cover the continental shelf where large Marine organism are present and there is enough sunlight algae organism use to photosynthesize and produce food for the Marine organisms by converting carbondioxide and water into carbohydrates.
The zone stretches from the surface , to the middle and depth of 200 m.
The surface zone is the area where light penetrates most , the transition stretches from the surface zone downward, in this zone light penetrates bit not as much as surface zone and in the deep zone, it stretches from the transition zone downward to a depth of 200 meters and don't have enough light penetration compare to surface and transition.
