chloroplast

American  

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

noun

Botany.

1. a plastid containing chlorophyll.

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chloroplast British  

/ ˈklɔːrəʊˌplæst /

noun

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

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chloroplast Scientific  

/ klôr′ə-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

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chloroplast Cultural  

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

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Other Word Forms

• chloroplastic adjective

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:

• chlorophyll vs. chloroplast

Example Sentences

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

When exposed to bright white light -- essentially the light of a sunny afternoon -- the cell's chloroplast shrunk to a ball, reducing its size by about 40% within five minutes.

From Science Daily • Nov. 18, 2024

The structure that allows the chloroplast to make these necessary changes was found to be a network of thin filaments.

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

In each assimilating cell there is usually a single large chloroplast.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3 "Brescia" to "Bulgaria" by Various