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chloroplast

American  
[klawr-uh-plast, klohr-] / ˈklɔr əˌplæst, ˈkloʊr- /

noun

Botany.
  1. a plastid containing chlorophyll.


chloroplast British  
/ ˈklɔːrəʊˌplæst /

noun

  1. a plastid containing chlorophyll and other pigments, occurring in plants and algae that carry out photosynthesis

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

chloroplast Scientific  
/ klôrə-plăst′ /
  1. A plastid in the cells of green plants and green algae that contains chlorophylls and carotenoid pigments and creates glucose through photosynthesis. In plants, chloroplasts are usually disk-shaped and can reorient themselves in the cell to vary their exposure to sunlight. Chloroplasts contain the saclike membranes known as thylakoids, which contain the chlorophyll and are arranged in stacklike structures known as grana. Besides conducting photosynthesis, plant chloroplasts store starch and are involved in amino acid synthesis. Like mitochondria, chloroplasts have their own DNA that is different from the DNA in the nucleus, and chloroplasts are therefore believed to have evolved from symbiont bacteria, their DNA being a remnant of their past existence as independent organisms.

  2. See more at cell photosynthesis


chloroplast Cultural  
  1. A chlorophyll-containing organelle found in algal and green plant cells.


Other Word Forms

Etymology

Origin of chloroplast

First recorded in 1885–90; chloro(phyll) + -plast

Compare meaning

How does chloroplast compare to similar and commonly confused words? Explore the most common comparisons:

Explanation

The chloroplast is the place in a plant cell where photosynthesis happens. Your rose bushes have chloroplasts, but you don’t. Chloroplast is the combination of two biological terms, plastid (an organelle in a plant cell), and chloros, which means green. If you’re reading about plant biology, you’ll probably recognize chloros in chlorophyll, which is one of the pigments important to photosynthesis, which takes place in chloroplasts.

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Vocabulary lists containing chloroplast

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

When the light conditions were changed to dim red light, within half an hour the chloroplast had returned to its original size and shape.

From Science Daily Nov. 18, 2024

Doing this under conditions of changing light colour and intensity, they could follow exactly what the cell's chloroplast was doing.

From Science Daily Nov. 18, 2024

Previous evolutionary trees of plants built by scientists often used the genome of the chloroplast, the organelle that allows plants to perform photosynthesis.

From New York Times May 11, 2024

Once you adjust the focus on the microscope, however, you see that the image of the nucleus becomes sharper while the image of the chloroplast blurs.

From Science Daily Mar. 5, 2024

The cell shows a division into two parts, and is often constricted in the middle,  each division having a single large chloroplast of peculiar form.

From Elements of Structural and Systematic Botany For High Schools and Elementary College Courses by Campbell, Douglas Houghton

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