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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Anatomical terminology | 4/4 | https://en.wikipedia.org/wiki/Anatomical_terminology | reference | science, encyclopedia | 2026-05-05T07:26:04.798609+00:00 | kb-cron |
Flexion and extension, which refer to a movement that decreases (flexion) or increases (extension) the angle between body parts. For example, when standing up, the knees are extended. Abduction and adduction refers to a motion that pulls a structure away from (abduction) or towards (adduction) the midline of the body or limb. For example, a star jump requires the legs to be abducted. Internal rotation (or medial rotation) and external rotation (or lateral rotation) refers to rotation towards (internal) or away from (external) the center of the body. For example, the lotus position posture in yoga requires the legs to be externally rotated. Elevation and depression refer to movement in a superior (elevation) or inferior (depression) direction. Primarily refers to movements involving the scapula and mandible.
=== Special motions of the hands and feet === These terms refer to movements that are regarded as unique to the hands and feet:
Dorsiflexion and plantarflexion refers to flexion (dorsiflexion) or extension (plantarflexion) of the foot at the ankle. For example, plantarflexion occurs when pressing the brake pedal of a car. Palmarflexion and dorsiflexion refer to movement of the flexion (palmarflexion) or extension (dorsiflexion) of the hand at the wrist. For example, prayer is often conducted with the hands dorsiflexed. Pronation and supination refer to rotation of the forearm or foot so that in the anatomical position the palm or sole is facing anteriorly (supination) or posteriorly (pronation). For example, if a person is holding a bowl of soup in one hand, the hand is "supinated" and the thumb will point away from the body midline and the palm will be superior; if the hands are typing on a computer keyboard, they will be "pronated" with the thumbs toward the body midline and the palms inferior. Eversion and inversion refer to movements that tilt the sole of the foot away from (eversion) or towards (inversion) the midline of the body.
== Muscles ==
Muscle action that moves the axial skeleton work over a joint with an origin and insertion of the muscle on respective side. The insertion is on the bone deemed to move towards the origin during muscle contraction. Muscles are often present that engage in several actions of the joint; able to perform for example both flexion and extension of the forearm as in the biceps and triceps respectively. This is not only to be able to revert actions of muscles, but also brings on stability of the actions though muscle coactivation.
=== Agonist and antagonist muscles === The muscle performing an action is the agonist, while the muscle whose contraction brings about an opposite action is the antagonist. For example, an extension of the lower arm is performed by the triceps as the agonist and the biceps as the antagonist (which contraction will perform flexion over the same joint). Muscles that work together to perform the same action are called synergists. In the above example synergists to the biceps can be the brachioradialis and the brachialis muscle.
=== Skeletal and smooth muscle ===
The gross anatomy of a muscle is the most important indicator of its role in the body. One particularly important aspect of gross anatomy of muscles is pennation or lack thereof. In most muscles, all the fibers are oriented in the same direction, running in a line from the origin to the insertion. In pennate muscles, the individual fibers are oriented at an angle relative to the line of action, attaching to the origin and insertion tendons at each end. Because the contracting fibers are pulling at an angle to the overall action of the muscle, the change in length is smaller, but this same orientation allows for more fibers (thus more force) in a muscle of a given size. Pennate muscles are usually found where their length change is less important than maximum force, such as the rectus femoris. Skeletal muscle is arranged in discrete muscles, an example of which is the biceps brachii. The tough, fibrous epimysium of skeletal muscle is both connected to and continuous with the tendons. In turn, the tendons connect to the periosteum layer surrounding the bones, permitting the transfer of force from the muscles to the skeleton. Together, these fibrous layers, along with tendons and ligaments, constitute the deep fascia of the body.
== Joints ==
Movement is not limited to only synovial joints, although they allow for most freedom. Muscles also run over symphysis, which allow for movement in for example the vertebral column by compression of the intervertebral discs. Additionally, synovial joints can be divided into different types, depending on their axis of movement.
== Body cavities ==
The body maintains its internal organization by means of membranes, sheaths, and other structures that separate compartments, called body cavities. The ventral cavity includes the thoracic and abdominopelvic cavities and their subdivisions. The dorsal cavity includes the cranial and spinal cavities.
== Membranes ==
A serous membrane (also referred to as a serosa) is a thin membrane that covers the walls of organs in the thoracic and abdominal cavities. The serous membranes have two layers; parietal and visceral, surrounding a fluid filled space. The visceral layer of the membrane covers the organ (the viscera), and the parietal layer lines the walls of the body cavity (pariet- refers to a cavity wall). Between the parietal and visceral layers is a very thin, fluid-filled serous space, or cavity. For example, the pericardium is the serous cavity which surrounds the heart.
== Additional images ==
== See also == Medical terminology Glossary of medicine Anatomical terms of bone Anatomical terms of muscle
== References ==
== Further reading == Calais-Germain, Blandine (1993). Anatomy of Movement. Eastland Press. ISBN 978-0-939616-17-6. Drake, Richard; Vogl, Wayne; Mitchell, Adam (2004). Gray's Anatomy for Students. Churchill Livingstone. ISBN 978-0-443-06612-2. Martini, Frederic; Timmons, Michael; McKinnley, Michael (2000). Human Anatomy (3rd ed.). Prentice-Hall. ISBN 978-0-13-010011-5. Marieb, Elaine (2000). Essentials of Human Anatomy and Physiology (6th ed.). Addison Wesley Longman. ISBN 978-0-8053-4940-5. Muscolino, Joseph E. (2005). The Muscular System Manual: The Skeletal Muscles of the Human Body (2nd ed.). C.V. Mosby. ISBN 978-0-323-02523-2. Ngai, Steven (2006). Understanding Anatomical Latin (PDF) (3rd ed.). Archived from the original (PDF) on 2009-03-25. Retrieved 2015-11-15. Losardo, R. J.; Valverde Barbato De Prates, N. E.; Arteaga-Martinez, M.; García Peláez, M. I.; Cabral, R. H. (2017). "International Morphological Terminology (anatomy, histology and embryology): beyond scientific terms". Journal of Morphological Sciences. 34 (3): 130–133. doi:10.4322/jms.109916. ISSN 2177-0298.
== Sources == This article incorporates text from a free content work. Licensed under CC BY 4.0. Text taken from Anatomy and Physiology, J. Gordon Betts et al, Openstax.