The Function & Cycle of the Twelve Primary Qi Meridians.
 

Yang

Yin

Lung [Yin] Metal
Time of Day  03:00-05:00 am (peak activity)
Directly related to respiration.
Indirectly to the heart & circulation.
Governs Qi & respiration, extracting pure Qi from the- environment & excreting dirty Qi.
Forms Qi in the chest along with stomach and spleen, this is the basis of Defensive & nutritive Qi, which the lung distributes Qi through out the body.
Controls channels and blood vessels
Disperses and descends Qi and body fluids
Regulates water passages
Controls skin & hair and opens into the nose
Houses the corporeal Soul.
Large Intestines  [Yang] Metal
Time of Day 05:00-07:00 am
Receives food and drink from Small intestine and absorbs remaining clean fluids and excretes the dirty portion of food as faeces.
Stomach [Yang] Earth
Time of Day 07:00-09:00 am
Churns and digests food for spleen to separate
Controls transport of food essences to muscles and limbs
Controls descending  action of Qi to Small intestine.
Spleen [Yin] Earth
Time of Day 09:00-11:00 am
Transforms nourishment from food to create Qi and Blood
Transports Food, fluids and Qi through out the body
Controls blood (in the blood vessels), muscles and Four limbs (arms & Legs)
Opens into mouth and lips
Controls rising action of Qi, food Qi to chest
Houses thought
Heart [Yin] Fire
Time of Day 11:00-13:00
Governs Blood
Transforms Food Qi into Blood
Controls Blood vessels
Manifests in complexion and opens into the tongue
Controls Sweat.
Anchors Mind.
Heart - our  relationship to self.
Small intestine [Yang] (Fire, clarity)
Time of Day 13:00-15:00
Separates the Pure food & fluids from the impure foods
Pure is taken in by the spleen
Impure goes to large intestine & Bladder
Discriminates and brings clarity.
Bladder [Yang] Water
Time of Day  15:00-17:00
Stores fluid and transforms fluid under the action of Qi supplied by kidney Yang
Receives impure fluids from Small intestines
Kidney [Yin] Water
Time of Day  17:00-19:00
Stores the Essence
Root of YIN & YANG
Governs growth, development & reproduction
Produces the Marrow (Brain, Bone, nerves, spinal cord)
Governs water
Controls reception of Qi and grasps & anchors the Qi inhaled from the lungs
Opens into the ears and manifests on the hair
Kidney Yang Heats kidney Yin & Essence which vaporizes as a mist of kidney Qi up to the lungs for dispersal.
Heart Protector [Yin] Fire
Time of Day  19:00-21:00
Closely related to heart, forms a protective layer / covering around the heart and other organs to guard them from attack (by climatic environment [ heat, cold], or emotions [hatred, etc.]), so shielding the mind contained in the heart from danger
Aids the heart in governing the blood and housing the mind

Heart Protector - our relationship to others.

Triple Heater [Yang] Fire
Time of Day  21:00-23:00
No Precise physical form / organ
Composes of 3 heaters
Upper [thorax] maintains a fine mist / vapour around lungs and heart
Mid [Upper Abdomen] maintains a flowing warmth for transport & digestion of nutrients in the stomach / spleen / liver
Lower [ abdomen] maintains control of the drainage of fluids in bladder & kidneys.
Controls water passages
Helps to warm organs
Sustains heart and brain functions
Helps to strengthen defensive Qi for protection i.e. from cold environment.
Gall-Bladder [Yang] Wood
Time of Day  23:00-01:00 am
Storage & excretion of Bile which aids digestion, bile is produced by the Liver
If Gall-bladder has imbalance then the liver is effected.
Controls courage.
Liver [Yin] Wood
Time of Day  01:00-03:00 am
Smooths the flow of Qi for physiological and emotional harmony
Stores the Blood
Controls muscles, tendons & ligaments
Manifests in the nails and opens into the eyes
Controls planning ability.

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