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

---

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

---

chloroplast Cultural  

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

---

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

One common trend is the reduction or loss of plastids -- a category of plant organelles that includes chloroplasts, which enable photosynthesis in most plants.

From Science Daily

Under Death Valley-level heat, the plant's mitochondria -- the structures that generate energy -- move closer to the chloroplasts, where photosynthesis occurs.

From Science Daily

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

However, it would appear that these "Tipp-Ex proteins" do not have permission to work in all areas of the cell, only being used in chloroplasts and mitochondria.

From Science Daily

As they put the new evolutionary tree together, they found that it confirmed many of the relationships suggested by trees built from chloroplasts.

From New York Times