Cell compartmentalization and its origins Show
Structure and function of mitochondria and chloroplasts. Endosymbiosis. Cell compartmentalization and its originsBiology is brought to you with support from the Amgen Foundation AP® is a registered trademark of the College Board, which has not reviewed this resource.
A eukaryotic cell has only three organelles that have a double-layered structure, namely, nucleus, mitochondria, and chloroplast., Here, we will discuss the two organelles of eukaryotic cells , mitochondria and chloroplasts, and their differences. Mitochondria and chloroplast are semiautonomous organelles that share various structural similarities but the major difference is their occurrence. Mitochondria are found in eukaryotic animal cells, whereas chloroplasts are found in plant cells. MitochondriaMitochondria are membrane-bound organelles found in almost all eukaryotic organisms. Their primary function is to generate energy in the form of adenosine triphosphate (ATP). It is commonly called a powerhouse of the cell. Additionally, they are able to generate heat, store calcium for cell signalling activities, cellular differentiation, mediate the cell cycle, and promote cell growth. Each human cell contains on average 100-1000 mitochondria. Almost all the genetic material is stored in every cell’s nucleus. Mitochondria have their own DNA and ribosomes. In most organisms, the Mitochondrial DNA is inherited maternally. The number of mitochondria varies in different organisms, tissues, and cell types. Usually, there are multiple mitochondria found in one cell depending on its function. Structure of Mitochondria Mitochondria have a double-layered membrane. They are rod-shaped or sausage-shaped organelles measuring 0.5-10μm in length. In a typical cell, they occupy almost 25% of the cell volume. Earlier mitochondria were represented as individual isolated organelles, now they form a dynamic connected network also called a reticulum. It has four main compartments mentioned below.
(Image will be uploaded soon) Functions of MitochondriaMitochondria are essential for aerobic metabolism. They are responsible for energy production through oxidative phosphorylation. Almost 90% of the cell’s energy is produced by them. They convert nutrients into Adenosine TriPhosphate (ATP) in the presence of oxygen (aerobic respiration). They maintain, replicate, and transcribe their own DNA. They are also involved in the synthesis of iron-sulfur clusters. ChloroplastsChloroplast is an organelle found in plants and green algae. It is a type of plastid that contains chlorophyll to absorb solar energy. It is green in colour due to the presence of two pigments -chlorophyll a and chlorophyll b. The chloroplast is a double-layered cell organelle. It is a semi-autonomous organelle that has its own DNA. It also contains thylakoids. The number of chloroplasts varies in different cells. Plants growing in shade contain larger chloroplasts in their cells than those which grow in intense light. Structure of Chloroplasts Chloroplasts differ in shape being plate-shaped in Chlorella, cup-shaped in Chlamydomonas, and in higher plants, they are spherical or ovoid. They measure 4-6μm in size. The chloroplasts have the following parts:
(Image will be uploaded soon) Functions of ChloroplastChloroplasts are the sites for photosynthesis where reactions take place to harness solar energy and convert it into chemical energy. They also carry out functions like the synthesis of fatty acids, amino acids, and membrane lipids. Plants do not have specialized immune cells, all cells participate in plant response. Mentioned below is the table that enlists the difference between mitochondria and chloroplast based on different parameters. Difference Between Mitochondria and Chloroplasts
Here, we learned about mitochondria, their structure, and their function. We have also learned about chloroplast structure and function. The difference between these semi-autonomous organelles is also covered in the article. Want to read offline? download full PDF here Download full PDF Is this page helpful? Recently Updated Pages Recently Updated Pages What is the difference between the mitochondria and the chloroplasts?Mitochondria are the "powerhouses" of the cell, breaking down fuel molecules and capturing energy in cellular respiration. Chloroplasts are found in plants and algae. They're responsible for capturing light energy to make sugars in photosynthesis.
What is true about mitochondria and chloroplasts?Mitochondria and chloroplast both are bounded by a double-membrane envelope and are semi-autonomous organelles. They both have their own genome (DNA) and also have their own ribosomes to synthesize proteins. Mitochondria and chloroplast can be found in the same plant cell.
Which of the following statements best describes the difference between mitochondria and chloroplast?Which statement best describes a relationship between mitochondria and chloroplasts? Mitochondria release chemical energy from molecules and store it in chloroplasts.
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