The skin is part of the integumentary system, and is also partly responsible for thermoregulation.

In warm climates, the skin helps lower body temperature by sweating and promoting vasodilation. It is able to open up pores to secrete sodium, which is followed by chloride and water. When water evaporates on the skin, it lowers the temperature of the skin because the water requires an input of thermal energy to transition to the gaseous state. Vasodilation in hot climates allows blood to exchange heat with the environment by flowing close to the skin.

In cold climates, the skin helps raise body temperature by promoting vasoconstriction and goose bumps (cutis anserina). Vasoconstriction helps prevent heat loss to the environment by reducing blood flow to regions of high surface area. Goose bumps raise the hairs in the skin to prevent convection from transferring heat away from the skin.

Sweat is produced in response to increased body temperature, which triggers a response from the hypothalamus that increases sweat secretion. Sweat is composed of water, sodium, and chloride ions. The evaporation of the water requires an input of energy (it is an endothermic process). This energy comes from the heat of the body, and is dissipated when the water transitions to the gaseous state. The byproduct is sodium chloride salt.

Endothelial cells are specialized to prevent clotting in their intact form. When disrupted, the endothelium retracts to expose the basement membrane. Proteins in this region will activate the clotting cascade.

Arterioles are the main type of vessel that regulates vessel size and pressure, and exchange over endothlieum can occur with or without fenestrations.

The arrector pili muscles are responsible for raising the hair shafts, producing "goose bumps" around the follicle. Arrector pili muscles are mostly vestigial, used for thermoregulation in mammals with more fur. In humans, the hair raise function is associated with fear and sexual arousal.

The stratum corneum encompasses the very top two layers of cells in the epidermis. It consists almost entirely of dead, keratinzed skin cells that have been pushed to the outermost layer. The stratum corneum forms a protective, waterproof barrier against the outside environment.

The stomach produces bicarbonate along the mucosal layer to neutralize the high acidity of the stomach. Without proper neutralization of the acid along the mucosal layer, the acid can directly destroy the barrier. When the acid destroys the mucosal layer, gastric ulcers may occur.  

Bone is considered a connective tissue. The hydroxyapatite crystal forms a generous amount of extracellular matrix, helping to connect the cells of the bone. This large amount of extracellular material is a defining characteristic of connective tissue.

Nervous tissue carries electrical impulses through the body. Muscular tissue is involved in contraction. Epithelium lines the biological lumens and areas exposed to the external environment, including the tracts for respiration, digestion, and excretion. Endothelium lines the tracts that are fully contained in the body, namely the circulatory system and heart chambers.

Ligaments serve to link bone to bone, mainly playing a role in stability rather than force transduction. Once a tendon has pulled on the bone, ligaments provide a mechanism for nearby bones to follow, allowing for a smooth and coordinated movement.

Tendons link skeletal muscle to bone. Cartilage is the main tissue of the ears and nose, and generally provides structure or biological cushioning. Adipose is fat tissue, responsible for storing water and nutrients for extended periods.

Tendons link skeletal muscle to bone. When skeletal muscle contracts and shortens, the tendon pulls the bone in the direction of the muscle contraction to propel movement.

Ligaments serve to link bone to bone, mainly playing a role in stability rather than force transduction. Cartilage is the main tissue of the ears and nose, and generally provides structure or biological cushioning. Adipose is fat tissue, responsible for storing water and nutrients for extended periods.

Skin is composed of epithelial cells, and is therefore not an example of connective tissue. The major types of connective tissue include bone, adipose, blood, and cartilage. Connective tissue is responsible for binding and support of other tissue.

Any tissues can essentially be broken down into epithelium (or endothelium), muscle tissue, neural tissue, or connective tissue.