Non-renewable resources are those natural resources that are available in limited quantity.

These resources cannot be renewed or replenished in short duration.

Examples are :: Natural gas, Petroleum, Coal,...

Lipids are molecules that contain hydrocarbons and make up the building blocks of the structure and function of living cells.

Examples of lipids include fats, oils, waxes,...

The most active phagocytic cells among the leukocytes (White Blood Cells) are neutrophils and monocytes.

The dermis is a layer of the skin of the integumentary system. The dermis lies deep to the superficial epidermis which is also the most superficial layer of the skin. The dermis lies superficial to the underlying hypodermis which is also referred to as subcutaneous tissue.

Among the components of the dermis are: sweat glands, hair follicles, collagen fibers, sensory- nerve endings and arrestor pill muscles.