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General Biology: Definitions and explanations page 3 PDF | Download eBooks

Learn general biology terms with definitions and explanations, biology terminologies (Page 3) for biology degree programs.


  1. What is Nuclear membrane?
    Nuclear pores are small openings on the membrane of the nucleus which allows the entering of ...
  2. What is Nucleolus?
    The nucleolus is the largest structure which is present inside the nucleus of eukaryotic cells. it ...
  3. What is Endoplasmic reticulum?
    The endoplasmic reticulum is an important organelle found in eukaryotic cells. this structure is absent in ...
  4. What is Golgi apparatus?
    The golgi apparatus is also called a golgi complex or golgi body. this structure is similar ...
  5. What is Lysosome?
    Lysosomes are special organelles that are surrounded by a membrane and maintain an acidic environment within ...
  6. What is Mitochondrion?
    Mitochondria are also called the powerhouse of the cell. it is the site where respiration takes ...
  7. What is Peroxisome?
    Peroxisomes are cytoplasmic organelles that have an important role in catabolic reaction. these organelles contain enzymes ...
  8. What is Vacuole?
    Vacuoles are closed sacs and are made of membranes. vacuoles have several kind of organic and ...
  9. What is Chloroplast?
    Just like the mitochondria in the animal cells the chloroplast function as the power house in ...
  10. What is Plasmodesmata?
    Much like the cell junctions in the animal cells, plasmodesmata in the plant cells help them ...
  11. What is Cell wall?
    A cell wall is a structural layer which surrounds certain types of cells including plant cells. ...
  12. What are Glycoproteins?
    Glycoproteins have important functions in the body. most of the secretory proteins are glycoproteins. the carbohydrate ...
  13. What are Transport vesicles?
    These vesicles are actually is a large structure within a cell that are enclosed by a ...
  14. What is Phagocytosis?
    Phagocytosis is the process by which a cell uses its plasma membrane to engulf a large ...
  15. What is Endosymbiont theory?
    This theory basically describes how a large host cell and ingested bacteria could easily become dependent ...
  16. What is Cristae?
    Cristae is basically the folding of the membrane of mitochondria. the cristae gives the inner membrane ...
  17. What is Mitochondrial matrix?
    The matrix of mitochondria is more viscous than the cell's cytoplasm as it contains less water ...
  18. What are Thylakoids?
    A thylakoid is a membrane-bound compartment inside chloroplasts and also many photosynthetic bacteria such as cyanobacteria. ...
  19. What is Grana?
    A typical chloroplast can have anywhere from 10 to 100 grana. it is the primary site ...
  20. What is Plastid?
    Plastids is the generic name given to specialized organelles that present in plants and have the ...
  21. What is Pseudopodia?
    A pseudopod is a temporary arm-like projection of a cell membrane of usually eukaryotes. this projection ...
  22. What is Extracellular matrix (ECM).?
    The extracellular matrix (ecm) is a three-dimensional network of extracellular macromolecules. many molecules are present in ...
  23. What are Tight junctions?
    Tight junctions basically have the function of binding adjacent epithelial cells in a narrow band just ...
  24. What are Desmosomes?
    Desmosomes are intercellular junctions that provide strong adhesion between cells. these junctions link adjacent cells through ...
  25. What are Gap junctions?
    Gap junctions are a specialized intercellular connection between a multitude of animal cell-types. they directly connect ...
  26. What is Amphipathic?
    The phospholipid is a classical example of an amphipathic molecule that has both the regions. they ...
  27. What is Diffusion?
    Diffusion is the movement of molecules from an area of high concentration to an area of ...
  28. What is Concentration gradient?
    A concentration gradient occurs where the concentration of any particles changes over a certain distance. for ...
  29. What is Passive transport?
    Passive transport is a movement of ions and other atomic or molecular substances across cell membranes ...
  30. What is Isotonic?
    Any body that has the same osmotic pressure as the other body. there will be no ...
  31. What is Hypotonic?
    Any body that has higher osmotic pressure as the other body. there will be net movement ...
  32. What is Hypertonic?
    Hypertonic refers to a solution with higher osmotic pressure than another solution. in other words, a ...
  33. What is Turgid?
    When plants are kept in a hypotonic environment, the water content inside the cells will be ...
  34. What is Flaccid?
    When a plant cell in an isotonic solution, the plasma membrane is not pressed tightly against ...
  35. What is Plasmolysis?
    When the cells are present in a hypertonic environment, they shrink as the water moves out ...
  36. What is Active transport?
    Many proteins facilitate this process as it cannot happen on its own. the movement of molecules ...
  37. What is Membrane potential?
    In all types of cells there is an electrical potential difference between the inside of the ...
  38. What is Proton pump?
    A proton pump is an integral membrane protein that helps the movement of protons inside or ...
  39. What is Exocytosis?
    Exocytosis is a form of active transport and bulk transport in which a cell transports molecules ...
  40. What are Ligands?
    A ligand is an ion or molecule (functional group) that binds to a central metal atom ...
  41. What is Metabolism?
    Metabolism is the set of life-sustaining chemical reactions in organisms. the three main purposes of metabolism ...
  42. What are Catabolic pathways?
    Catabolism is the set of metabolic pathways that breaks down molecules into smaller units that are ...
  43. What are Anabolic pathways?
    Anabolism is the set of metabolic pathways that construct molecules from smaller units. these reactions require ...
  44. What are Thermodynamics?
    Thermodynamics deals with the relationships between heat and other forms of energy. in particular, it describes ...
  45. What is Entropy?
    Entropy is the measure of a system's thermal energy per unit temperature. this energy is used ...
  46. What is Activation energy?
    The activation energy is the energy that is required to start a reaction. this energy must ...
  47. What is Active site?
    The active site is the region of an enzyme where substrate molecules bind and undergo a ...
  48. What is Cofactor?
    A cofactor is a non-protein chemical compound or metallic ion that is required for an enzyme's ...
  49. What is Allosteric regulation?
    Allosteric regulation is basically the regulation of an enzyme by binding an effector molecule at a ...
  50. What is Exergonic reaction?
    An exergonic reaction is a chemical reaction where the change in the free energy is negative. ...
  51. What is Endergonic?
    An endergonic reaction is a chemical reaction in which the standard change in free energy is ...
  52. What is Fermentation?
    This process has different definitions in biochemistry and biological terms. here fermentation is being referred to ...
  53. What is Aerobic respiration?
    Aerobic respiration is the process that produces cellular energy by using oxygen. cells break down food ...
  54. What is Redox Reaction: Oxidation?
    When a specie gains protons or oxygen atoms its said to have oxidizing properties. in other ...
  55. What is Reduction?
    Reduction is the gain of electrons or a decrease in the oxidation state of an atom ...
  56. What is Reducing agent?
    The agent is itself being oxidized is called the reducing agent. a reducing agent is typically ...
  57. What is Oxidizing agent?
    The agent that is itself being reduced is called the oxidizing agent. so in any redox ...
  58. What is Electron transport chain?
    An electron transport chain is a series of complexes that transfer electrons from electron donors to ...
  59. What is ATP synthase?
    The atp synthase is a mitochondrial enzyme that is present in the inner membrane. it has ...
  60. What is Chemiosmosis?
    Chemiosmosis is the movement of ions across a semipermeable membrane, down their electrochemical gradient and the ...