nucleolus organiser
Học thuậtThân thiện
The nucleolus organiser is visible as a distinct region within the cell nucleus.
Definition
- Noun:
- A specific chromosomal region: The "nucleolus organiser" is the particular part of a chromosome that is associated with a nucleolus after nuclear division. It contains the genes for ribosomal RNA (rRNA) and is the site where the nucleolus forms.
Usage
- The term is used in cell biology and genetics to describe a functional region of a chromosome.
- It is a countable noun. Example: "The nucleolus organiser regions on these chromosomes are highly active."
Examples
- Noun:
- Scientists studied the nucleolus organiser to understand ribosome synthesis.
- Mutations in the nucleolus organiser can disrupt the formation of the nucleolus.
Advanced Usage
- "Nucleolus organiser region (NOR)": This is the full technical term often abbreviated as NOR. It refers to the chromosomal segment containing the rRNA genes.
- The nucleolus organiser region is visible under a microscope after specific staining.
Variants and Related Words
- Nucleolus organizer: An alternative spelling, primarily used in American English.
- NOR (abbreviation): A common abbreviation for "nucleolus organiser region."
Synonyms
- NOR (Nucleolus Organiser Region): The abbreviated form is often used synonymously.
- Ribosomal DNA (rDNA) locus: While not perfectly identical, this term refers to the specific DNA sequences within the nucleolus organiser that code for rRNA.
Notes on Meaning
- The term specifically denotes a or on a chromosome, not the nucleolus itself. Its primary function is to organise the formation of the nucleolus, a sub-structure within the cell nucleus.
The nucleolus organiser is visible as a distinct region within the cell nucleus.
Noun
- the particular part of a chromosome that is associated with a nucleolus after nuclear division