Meaning & use
chromosome
Last updated
Meanings
nouncountablebiology
A long, tightly packed strand of DNA and protein inside a cell that holds its genes and is copied and passed on when cells divide.
Grammar: Countable: humans have 23 pairs of chromosomes, not one chromosome pair of many.
Patterns
- a chromosome of something
- chromosomes in something
Each human cell nucleus normally contains 46 chromosomes.
Before a cell divides, every chromosome is copied.
A missing piece of a chromosome can cause serious health conditions.
nouncountablebiology
One of the two sex chromosomes, called X and Y, that help determine whether a person or animal develops as female or male.
Grammar: Usually named by letter: an X chromosome, a Y chromosome.
Patterns
- an X chromosome
- a Y chromosome
Most females inherit an X chromosome from each parent.
The Y chromosome is much smaller than the X chromosome.
Birds use a different pair of sex chromosomes from mammals.
Word forms
| plural | chromosomes |
|---|
Common combinations
- sex chromosome
- The sex chromosome a child inherits from the father is either X or Y.
- pair of chromosomes
- Humans have 23 pairs of chromosomes.
- chromosome number
- The chromosome number differs widely between species.
- chromosome abnormality
- A chromosome abnormality was found in the test results.
- copy a chromosome
- Enzymes help copy a chromosome before the cell splits.
Synonyms and how they differ
- chromatin
- Chromatin is the loose DNA-protein material in a resting cell, whereas a chromosome is the condensed, visible form during division.
- genome
- The genome is the full set of genetic material, while a chromosome is just one packaged piece of it.
- DNA strand
- A DNA strand is a single molecule chain, but a chromosome includes the DNA together with its supporting proteins.
Word family
Commonly confused: chromosome or chromatin? chromosome or gene?
chromosome vs chromatin
Chromatin is the uncoiled material in a nondividing cell, while a chromosome is the tightly coiled structure seen during division.
chromosome vs gene
A gene is a short stretch of DNA with a specific instruction, while a chromosome carries many thousands of genes.
Practice
A typical human body cell nucleus contains 46 ____.
Choose one answer.
Humans have 46 chromosomes in most cells. Genes number in the tens of thousands, so 46 genes would be far too few.
Make it your own
Write a sentence using “chromosome”, then check it and compare it with the examples above.