Difference Between Grana and Stroma

Main Difference – Grana vs Stroma

Grana and stroma are two structures of chloroplast. Chloroplast is the organ where reactions of photosynthesis take place. The main difference between grana and stroma is that grana are the disk-like plates embedded in the stroma whereas stroma is the homogeneous, jell-like matrix of the chloroplast. Grana are connected to each other by intergranal lamellae. They contain different pigments such as chlorophyll-a, chlorophyll-b, carotene, and xanthophyll. Light reaction of photosynthesis occurs in the grana. Stroma dissolves the enzymes required for photosynthesis, cytocrome system, DNA and RNA of the chloroplast. Dark reaction of photosynthesis occurs in the stroma.

Key Areas Covered

1. What are Grana
      – Definition, Structure, Function
2. What is Stroma
      – Definition, Structure, Function
3. What are the Similarities Between Grana and Stroma
      – Outline of Common Features
4. What is the Difference Between Grana and Stroma
      – Comparison of Common Features

Key Terms: Chloroplast, Dark Reaction, Grana, Light Reaction, Photosynthesis, Stroma, Thylakoid

Difference Between Grana and Stroma - Comparison Summary

What are Grana

Grana refer to the stacks of thylakoids embedded in the stroma of a chloroplast. A combination of 2 to 100 thylakoids may form a granum. A single chloroplast may contain 10 to 100 grana. Grana are connected with each other by stromal thylakoids. Therefore, all grana in a particular chloroplast may act as a single functional unit. Stromal thylakoids are also called intergranal thylakoids or lamellae. Both thylakoid and stromal thylakoid contain photosynthetic pigments on their surfaces. On that account, the light reaction of photosynthesis occurs on the surface of grana. A granum is shown in figure 1.

Main Difference - Grana vs Stroma

Figure 1: Granum

Thylakoid is a round pillow-shaped stack inside the chloroplast. The space between thylakoid membrane is called thylakoid lumen. Chlorophyll and other photosynthetic pigments are held by membrane proteins on the surface of the thylakoid. They are organized into photosystem 1 and 2 on the thylakoid membrane.

What is Stroma

Stroma refers to a colorless jell-like matrix of the chloroplast in which the dark reaction of photosynthesis takes place. Enzymes required for the dark reaction are embedded in the stroma. Stroma surrounds the grana. In the stroma, carbon dioxide and water are used in the production of simple carbohydrates by using the light energy trapped by light reaction. Stroma and grana of a chloroplast are shown in figure 2.

Difference Between Grana and Stroma

Figure 2: Structure of a Chloroplast

Dark reaction of photosynthesis is also called the Calvin cycle. The three stages of the Calvin cycle are carbon fixation, reduction reactions, and RuBP regeneration.

Similarities Between Grana and Stroma

  • Both grana and stroma are two structures of the chloroplast.
  • Reactions of photosynthesis occur in both grana and stroma.

Difference Between Grana and Stroma

Definition

Grana: Grana refers to the stacks of thylakoids embedded in the stroma of a chloroplast.

Stroma: Stroma refers to a colorless jell-like matrix of chloroplast in which the dark reaction of photosynthesis takes place.

Structure

Grana: Grana are the disk-like plates in the stroma.

Stroma: Stroma is the jell-like matrix of the chloroplast.

Components

Grana: Grana consist of different pigments such as chlorophyll-a, chlorophyll-b, carotene, and xanthophyll.

Stroma: Stroma consists of enzymes required for photosynthesis, cytochrome system, DNA, and RNA of the chloroplast.

Reactions of Photosynthesis

Grana: The light reaction of photosynthesis occurs in the grana.

Stroma: The dark reaction of the photosynthesis occurs in the stroma.

Role

Grana: Grana provide a large surface for the attachment of photosynthetic pigments.

Stroma: Stroma embeds enzymes required by the dark reaction of photosynthesis.

Conclusion

Grana and stroma are two structures of chloroplast. Grana are the stacks of thylakoids where light reaction of photosynthesis takes place. Stroma is the jell-like matrix of the chloroplast, which contains the enzymes for dark reaction of photosynthesis. The main difference between grana and stroma is their structure and function.

Reference:

1.“Granum.” Plant Biology, .
2.“Stroma Function.”  Plant Biology, .

Image Courtesy:

1. “” via
2. “Chloroplast-new” (Public Domain) via

About the Author: Lakna

Lakna, a graduate in Molecular Biology & Biochemistry, is a Molecular Biologist and has a broad and keen interest in the discovery of nature related things

Leave a Comment


Related pages


guar gum xanthan gumis bread soda and bicarbonate of soda the same thingtips on how to memorize a speechdifference between wifi and wimaxdifference between hotel motel and innmacro vs micro evolutionnpn transistor and pnp transistorformula of maltosedefinition of rotatory motionwhat is the difference between denotative and connotative meaningwhat is the difference between danish and dutchdiffusivity definitionplant vs animal mitosisvalence shells definitionbaking soda & bicarbonate of soda differencedefinition of heteronymabiotic definitionwhat is the difference between an agnostic and atheistmonocot vs dicot stembosons and fermionsfinding the area of a regular hexagonwhat is the difference between waiting and awaitingtons vs tonnesmaid vs matronastronomy vs astrologyare sonnets poemswhat is the difference between insulator and conductordistinguish mitosis from meiosisdifference between values and virtueswhat is the moral of goldilocks and the three bearscacophony meanswhat are examples of concrete nounsdefinition aliphaticwhat is the difference between comedy and tragedydifference between algae and fungipomelo citrusalkaline earth metals definitiontesting for halide ionsthe main difference between prokaryotic and eukaryotic cells is thatwhat is metabolism and catabolismc pap vs bi papwhat is the difference between a seizure and epilepsyautotrophs and heterotrophs differencesdifference between anecdote and storyenantiomers vs diastereomers examplesstratified epithelial tissue structuredifference between jealous and enviousarea of quadrilateral with unequal sidesdefinition for third person omniscientdifference between male and female cannabis plantswhat is the distinction between a seed and a fruitatmosphere definition literary termwhat is the difference between homophones and homographsdifference between orbit and rotationdifferences between diffusion and osmosisnonpolar examplesashok chakra meaningwhat is total owners equitydifferences between hiv and aidsviner calipervanitymeaningare broccoli and cauliflower the same plantis baking soda same as bicarb sodadifference between intermolecular forces and intramolecular forcesattenuation ultrasoundprejudice vs stereotypemicrotubules microfilamentswhat is the difference between fairies and pixieshow to find the apothem of a octagondifference between mitosis and meiosis cell divisionhow do van der waals forces hold molecules togetherhow to tell difference between yam and sweet potatoferric metaleubacteria and archaeapumello fruitoogenesis definition