(2) a layer of thick fat Explanation: Blubber is a thick layer of vascularized adipose tissue found under the skin. Lipid-rich, collagen fiberlaced blubber comprises the hypodermis and covers the whole body, except for parts of the appendages, strongly attached to the musculature and skeleton by highly organized, fan-shaped networks of tendons and ligaments. It can comprise up to 50% of the body mass of some marine mammals during some points in their lives.