epiphysis
/e'pifisis/
Học thuậtThân thiện
Definition
- Noun:
- A small endocrine gland in the brain: The epiphysis, also known as the pineal gland, is a small, pinecone-shaped endocrine gland located in the brain. It is situated beneath the posterior part of the corpus callosum and is responsible for secreting the hormone melatonin, which regulates sleep-wake cycles.
- The end of a long bone: In anatomy, an epiphysis is the rounded end of a long bone. Initially, it is separated from the main shaft of the bone (the diaphysis) by a layer of cartilage (the epiphyseal plate or growth plate). This cartilage eventually ossifies (turns to bone) and fuses with the diaphysis, signaling the end of bone growth.
Usage Examples
- Referring to the brain gland:
- The epiphysis, or pineal gland, plays a crucial role in regulating circadian rhythms.
- Melatonin secretion from the epiphysis helps signal to the body that it is time to sleep.
- Referring to the bone end:
- A fracture in the epiphysis of a child's femur requires careful medical attention.
- The epiphysis fuses with the diaphysis during late adolescence.
Advanced Usage
- "Epiphyseal plate" (or growth plate): The area of cartilage between the epiphysis and diaphysis in a growing bone.
- Damage to the epiphyseal plate can stunt bone growth.
- "Epiphyseal fusion": The process where the epiphyseal plate ossifies and the epiphysis joins with the diaphysis.
- Epiphyseal fusion is used to estimate skeletal age.
Variants and Related Words
- Epiphyseal (adj): Pertaining to an epiphysis.
- The doctor examined the epiphyseal region on the X-ray.
- Diaphysis (n): The main or midsection (shaft) of a long bone.
- The fracture occurred in the diaphysis of the humerus.
- Pineal gland (n): Another name for the epiphysis cerebri (the brain gland).
- Calcification of the pineal gland is sometimes visible on brain scans.
Synonyms
- For the gland: Pineal gland, pineal body, conarium.
- For the bone end: Bone end, articular end (in some contexts).
Related Terms and Phrases
- "Slipped capital femoral epiphysis (SCFE)": A medical condition where the epiphysis of the femur slips off the neck of the bone.
- SCFE is a common hip disorder in adolescents.
- "Epiphysis cerebri": The full anatomical term for the pineal gland.
- The epiphysis cerebri is part of the epithalamus.
Noun
- a small endocrine gland in the brain; situated beneath the back part of the corpus callosum; secretes melatonin
- the end of a long bone; initially separated from the main bone by a layer of cartilage that eventually ossifies so the parts become fused