Answer:
1) Skull and Vertebral column
2) Meninges
3) Cerebrospinal fluid.
Explanation:
Central Nervous system:
CNS is the abbreviation of Central Nervous system. CNS controls the whole body functions so it is the most important component of the body. CNS consist of two parts 1) Brain and 2) Spinal cord
Both of these organs are very important and hence need to be protected. Nature provided these organs with certain protective mechanisms these includes
1) Skull and Vertebral column:
Skull is present around brain and vertebral column is present around spinal cord. These structure provides mechanical support to soft parts of CNS.
2) Meninges:
These are the membranes that provide antiseptic environment to the brain and hence protect it from microbes and other harmful substances.
3) Cerebrospinal fluid:
This fluid is present inside meninges which nourishes the brain and protect it from mechanical stresses.
If not parents had a recessive type O allele, they would have a 1/4 or 25% chance of having a child with type O blood
Answer:
Invertebrates include all animals that lack a backbone, or a vertebral column. All chordites exhibit four characteristics during at least one stage of life: a dorsal, hollow nerve chord; a notochord; a tail that extends beyond the anus; and pharyngeal pouches.
