Stole the image from the question directly above yours. 50% of the offspring are heterozygous (Aa) and red. The other 50% are homozygous recessive (aa) and white.
50% of the offspring will have the "Aa" alleles and for this reason they will have the dominant, red characteristic.
50% of the offspring will have the "aa" alleles and for this reason, they will have a white, recessive characteristic.
Explanation:
The punnet square shown in the question above is filled in the figure attached below. In it, we can see that the cross between a living being with the "Aa" alleles and a living being with the "aa" alleles would result in 50% "Aa" and 50% "aa" offspring. Those who have the dominant allele "A" will have a dominant characteristic of red color, while those who do not have the dominant allele, will have a recessive characteristic of white.
The protective covering of the brain
that provides passageways for cerebrospinal fluid (CSF) to drain into the
superior sagittal sinus is called the arachnoid mater.
To add, the arachnoid mater is the middle
of three layers that make up the meninges, or membranes, that surround the spinal
cord and brain.