It also help in the detection of sensations The adipose tissue has metabolic
and give strength and flexibility to the functions: it is responsible for production
skin. of vitamin D, and triglycerides.
Components of the dermis include: DIGESTIVE SYSTEM or Excretory system
Blood vessels - transport oxygen and nutrients It is a group of organs working together to
to the skin and remove waste products. These convert food into energy and basic
vessels also transport vitamin D from the skin nutrients to feed the entire body.
to the body. Food passes through a long tube inside the
body known as the alimentary canal or the
Lymph vessels - supply lymph (milky fluid
gastrointestinal tract (GI tract).
containing white blood cells of the immune
The alimentary canal is made up of the
system) to skin tissue to fight microbes.
oral cavity, pharynx, esophagus, stomach,
Sweat glands - regulate body temperature by small intestines, and large intestines.
transporting water to the skin"s surface where The entire system from mouth to anus is
it can evaporate to cool down the skin. about 30 feet (9 meters) long.
To providing energy and nutrients to the
Sebaceous (oil) glands - secret oil that helps body, six major functions take place in the
to waterproof the skin and protect against digestive system: ingestion, secretion,
microbe build-up. They are attached to hair mixing and movement, digestion,
follicles. absorption, excretion.
Hair follicles - tube-shaped cavities that
enclose the hair root and provide nourishment
to the hair.
Sensory receptors - nerve endings that
transmit sensations such as touch, pain, and
heat intensity to the brain.
Collagen - tough structural protein that holds
muscles and organs in place and gives strength
and form to body tissues.
Elastin - rubbery protein that provides
elasticity and makes the skin stretchable. It is
also found in ligaments, organs, muscles and
artery walls.
Hypodermis (Subcutis)
Digestive system components
The innermost layer of the skin is the
hypodermis. Mouth
This layer is underneath the dermis, and
The mouth is the first part of the
merges with it.
gastrointestinal tract and is equipped with
It mainly contains adipose tissue and several structures that begin the first
sweat glands. processes of digestion. These include
salivary glands, teeth and the tongue.
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