Hypodermis

The hypodermis, also called the hypoderm, subcutaneous tissue, or superficial fascia is the lowermost layer of the integumentary system in vertebrates. Types of cells that are found in the hypodermis are fibroblasts, adipose cells, and macrophages. It is derived from the mesoderm, but unlike the dermis, it is not derived from the dermatome region of the mesoderm. In arthropods, the hypodermis is an epidermal layer of cells that secretes the chitinous cuticle. The term also refers to a layer of cells lying immediately below the epidermis of plants.

This cell is also used to supervise the outer skin from burns and other such articulates.

The hypodermis is used mainly for fat storage.

A layer of tissue that lies immediately below the dermis of vertebrate skin. It is often referred to as subcutaneous tissue though this is a less precise and anatomically inaccurate term. The hypodermis consists primarily of loose connective tissue and lobules of fat. It contains larger blood vessels and nerves than those found in the dermis.

Specifically, the hypodermis contains:

• Loosely arranged elastic fibers
• Fibrous bands anchoring the skin to the deep fascia
• Fat, except in the eyelid, scrotum, penis, nipple and areola
• Blood vessels on route to the dermis
• Lymphatic vessels on route from dermis
• Hair follicle roots
• The glandular part of some sudiferous glands
• Nerves: free endings and Panicinian corpuscles
• Bursae, in the space overlying joints in order to facilitate smooth passage of overlying skin
• Fine, flat sheets of muscle, in certain locations, including the scalp, face, hand, nipple, and scrotuim, called the panniculus carnosus

In some animals, such as whales and hibernating mammals, the hypodermis forms an important insulating layer and/or food store.

In some plants, the hypodermis is a layer of cells immediately below the epidermis of leaves. It is often mechanically strengthened, for example, in pine leaves, forming an extra protective layer or a water storage tissue.

According to the eighth edition of Developmental Biology by Scott F. Gilbert, the hypodermis of C. elegans is derived from ectoderm.