The answer is D
One way to remember this is when you are building a bridge there is one piece right in the middle that keeps the whole thing from collapsing that is called the key-stone. If a keystone species goes extinct then the rest of the ecosystem will crumble around it.
Answer:
Produced by the choroid plexus -T.This is the major secretion site.It is also produced in smaller quantities in the interstitial compartment.
Blocks blood toxins from brain tissue-F, that is the job of the blood brain barrier(BBB).
Supplies oxygen to the brain tissue-T.This gas is dissolved in the CSF together with CO2 for distribution among nervous tissues by the CSF
Maintains the concentration of glycine surrounding the brain-T
Found in the ventricles of the heart and brain-False,it does not reach the heart ventricles.This are occupied by blood.
Prevents concussions-T
Produces antibodies in response to antigen exposure in the brain tissue-False.These are produced by the B-cells, not by in the CSF,based on the specif antigen stimulation.
Effectively decreases the brain's weight-T It reduces the weight of the brain.This is done by the buoyancy it provided for the brain.
Compared to levels in the blood plasma, the CSF is higher in glucose-F.This is wrong, the glucose of the blood plasma is higher.But equal sodium ion,more chloride in CSF, and less protein.It s levels is a relefection of blood glucose.Although it may lag 2-4hrs in the CSF.
It prevents concussion,(T)and and the contraction of cardiac muscles propels its movement(T).
Explanation:
Produces water should be in the only aerobic section of the diagram. Aerobic respiration end products are carbon dioxide and water. Anaerobic respiration end products are lactic acid in animals and carbon dioxide and ethanol in yeast and plants. (:
Answer:
4
Explanation:
Number 4 is the cytoplasm.
