other cell structures

• The complex structure of cells can be seen in more detail using an electron microscope.
• These microscopes can achieve magnifications of up to ×500 000. This allows structures that are visible using a light microscope to be studied in more detail. It also allows even smaller structures to be seen.
• For example, ribosomes are visible only through an electron microscope. 
• Similarly, while chloroplasts and mitochondria can be viewed through a light microscope, their complex structure is seen only under an electron microscope.
• ribosomes = Sub-cellular structures in which protein synthesis takes place.
• mitochondria = (singular: mitochondrion) Sub-cellular structures that release energy for the cell by aerobic respiration.
• chloroplasts = Sub-cellular structures found in some plant cells; the site of photosynthesis.
• Ribosomes are found either scattered freely in the cytoplasm or at times attached to a network of tube like membranes seen in the cytoplasm.
• Mitochondria are present in both plant and animal cells.
• Mitochondria are larger than ribosomes
• In aerobic respiration process, useful energy is released when glucose is broken down in the presence of oxygen (producing carbon dioxide and water). 
• Cells with high rates of metabolism (such as liver and muscle cells) have many mitochondria.
• having many mitochondria ensures that these cells (with high rate of metabolism) have a good supply of energy.
• Chloroplasts are present in photosynthetic organisms, such as plants and certain algae.
• chloroplasts contain the photosynthetic pigment chlorophyll, which absorbs light energy and converts it into chemical energy, glucose. 
• • the nucleus and ribosomes (the tiny ‘blobs’) attached to a network of tube-like membranes
  • three mitochondria, a large one and two smaller ones

  
• mitochondria under electron microscope

  
• internal structures of mitochondrion
• chloroplasts in plant cells

  
• internal structures of a chloroplast
• internal structures of chloroplast