4 billion years ago the temperature was much higher due to repeated volcanoes and hot gases present in the atmosphere. There weren't any live forms on earth. ... The atmosphere had a different concentration of gases on the earth. There were no life sustaining gases.
No, because its genes are still the same. To evolvewould mean that the frog had one set of genes as a tadpole, then a different set as an adult. It just doesn't work that way. The genes are the same.
<span> the water compound of </span><span>H2O</span><span>. hope this helps </span>
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:
