Answer:
A I think sorry if its wrong
The outer periphery of the inter-vertebral disk is composed of strong fibrous tissue called the Annulus fibrosus. This is a tough circular exterior of the inter-vertebral disc that surrounds the soft inner core, the nucleus pulposus. The outer portion is composed of a ring of ligament fibers that encases the inner core of the disc and securely connects the spinal vertebrae above and below the disc.
Answer:
The correct answer is C) arachnoid mater.
Explanation:
Arachnoid mater, along with pia mater and dura mater, form the <u>meninges</u>, a very thick membrane that protects the brain and the spinal cord. The arachnoid mater is in the middle of the other two layers and it is very important since it holds the <u>cerebrospinal fluid (CSF)</u> in its interior. Arachnoid mater has finger-like projections that enter the dural venous sinuses and are called <u>arachnoid villi</u>. These villi are responsible for the diffusion of CSF into the blood.
Insects are very common not only in today's world but also in ancient days. It is also estimated that the population of insect are 10 times more than thehuman beings. It is little bloodcurdling to hear but it is the fact. They are found in all parts of the world even in the ocean. Insects are astonishing creatures it is quite interesting to learn about them. Insects are very advantageous to man and his environment.
Insects are small species that is characteristic as an air breathing animal with a hard jointed exoskeleton. The whole body of the insects is divided into three parts: The head, thorax, and the abdomen.
Insects are classified into different known species in the world but still some new species are being discovered. The known species can be classified into 32 orders with 125 different families and about 500,000 species. Among them the Beetles are the largest group. Insects act as the varied group in the animal world.
Many insects act as the primary consumers for other animals since they are herbivores. These insects are rich in protein and energy which they provide to the secondary consumers also known as carnivores. Spiders, wireworms etc, act as the secondary consumers which cannot survive without depending on the primary consumers. Both the primary and secondary act as the prey to the tertiary consumers.
Insects help with a lot of important functions in our ecosystem. Mainly they help in decomposition of the waste products and pollination. These two acts of the insects led a greener environment. Decomposition of dead and waste materials provides more nutrients to the soil thus helping the soil to regain its health. Bugs such as ants, beetles burrow the soil to provide channels for water and air ventilation to the soil. Bees help in pollution thus helping in plantation. Bugs help the gardeners by preventing the plants from aphids and caterpillars. So without insects the world would not have see a fast growth that the way it is today.
Insects are exceedingly a diverse type of animal. The structure of the insects varies greatly with the different types of species. But the basic anatomy of the insect is the same. All the insects have an external exoskeleton and the body is divided into three major segments: head, thorax, and abdomen
Its a large ductless gland in the neck that secretes hormones regulating growth and development through the rate of metabolism.
