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

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.

Example Sentences

Its main source of energy is sunlight: similar to plants, it uses a structure known as a chloroplast to convert energy from sunlight into useable, chemical energy.

From Science Daily • Nov. 18, 2024

What the researchers found was that while the chloroplast cannot escape intense light, it can minimize its effect by shrinking.

From Science Daily • Nov. 18, 2024

Biophysicists Nico Schramma, Gloria Casas Canales and Maziyar Jalaal devised a clever way to study what exactly happens to the chloroplast of P. lunula when it is exposed to light.

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 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