The subarachanoid space lies between the arachnoid and pia mater. It is filled with cerebrospinal fluid. All blood vessels entering the brain, as well as cranial nerves pass through this space. The term arachnoid refers to the spider web like appearance of the blood vessels within the space.
Why do biologists organize living things into groups? What do the levels of classification indicate about the relationship between organisms? What characteristics are used to classify organisms into domains and kingdoms? What is the scientific study of how living things are classified called? Taxonomy
Choose a question -. Scientists group things together into groups with similar characteristics, a process called taxonomy, to build a structure called The Tree of Life.Taxonomy groups all living things together in groups that seperate out some but not others, so we can give names to groups of animals with similar characteristics.hoose a question -. Scientists group things together into groups with similar characteristics, a process called taxonomy, to build a structure called The Tree of Life.