General Biology: Definitions and explanations page 12 PDF | Download eBooks

Learn general biology terms with definitions and explanations, biology terminologies (Page 12) for biology degree programs.


  1. What is Orbital?
    Orbital is a technical way of describing a path of an object. so an atoms orbital ...
  2. What are Organ identity genes?
    A great deal of attention has focused on the genes that specify organ identity, leading to ...
  3. What is Organ?
    A recognizable structure of the body that has a particular function is called an organ. an ...
  4. What is Organelle?
    Organelles are much like organs of the body in terms of function. they are small compartments ...
  5. What is Organic chemistry?
    The study of compounds that have at least one carbon atom is called organic chemistry. the ...
  6. What are Organisms?
    An individual entity that inhabits a place. organisms are classified in to groups based on their ...
  7. What is Organogenesis?
    Organogenesis is the stage of embryonic development that starts at the end of gastrulation and lasts ...
  8. What is Origins of replication?
    Origin of replication is by definition, the area where replication starts. in bacteria there is usually ...
  9. What are Orthologous genes?
    Orthologs are genes that are related by vertical descent from a common ancestor and encode proteins ...
  10. What is Osmolarity?
    Osmolarity is another name for osmotic concentration which measures the solute concentration. it is caluculated as ...
  11. What is Osmoregulation?
    Osmoregulation is the active regulation of the osmotic pressure of an organism's body fluids which happens ...
  12. What is Osmosis?
    Osmosis is the spontaneous net movement of solvent molecules through a selectively permeable membrane into a ...
  13. What is Ovaries?
    The ovary is an impotant organ in the female reproductive system that produces an ovum. when ...
  14. What is Over nourishment?
    Overnutrition or hyperalimentation is a form of malnutrition in which the intake of nutrients is oversupplied. ...
  15. What is Ovulation?
    Ovulation is the discharge of eggs from the ovaries. this even happens when ovarian follicles break ...
  16. What is Oxidizing agent?
    The agent that is itself being reduced is called the oxidizing agent. so in any redox ...
  17. What is P generation?
    P generation is the name given to the parental generation. the parent plants are usually denoted ...
  18. What is p53 gene?
    P53 is an example of a tumor suppressor gene that encode a specific transcription factor that ...
  19. What is Paleoanthropology.?
    Paleoanthropology is a branch of archaeology with a human focus. it seeks to understand the early ...
  20. What is Paleontology?
    Paleontology, sometimes spelled paleontology is the scientific study of life that existed prior to, and sometimes ...
  21. What is Palisade mesophyll?
    Palisade cells are plant cells located on the leaves, right below the epidermis and cuticle. they ...
  22. What is Pancreas?
    The pancreas is an organ of the digestive system and endocrine system of vertebrates. in humans, ...
  23. What is Pandemic?
    A pandemic is an epidemic or an outbreak of an infectious disease, that spreads worldwide. when ...
  24. What is Pangea?
    Pangaea or pangea was a supercontinent that existed during the late paleozoic and early mesozoic eras. ...
  25. What is Paralogous genes?
    Paralogs are homologous genes that have evolved by duplication and code for protein with similar, but ...
  26. What are Parasitic plants?
    Many species of these parasitic plants have roots that function as haustoria, nutrient-absorbing projections that tap ...
  27. What is Parasitism?
    Parasitism is a relationship between species, where one organism, the parasite, lives on or in another ...
  28. What is Partial pressure?
    In a mixture of gases, each constituent gas has a partial pressure which is the notional ...
  29. What is Passive immunity?
    A different type of immunity results when the igg antibodies in the blood of a pregnant ...
  30. What is Passive transport?
    Passive transport is a movement of ions and other atomic or molecular substances across cell membranes ...
  31. What is Pathogen-associated molecular patterns (PAMPs)?
    These molecules can be referred to as small molecular motifs conserved within a class of microbes. ...
  32. What is Pathogen?
    A pathogen is anything that can produce disease. a pathogen may also be referred to as ...
  33. What are Pathogens?
    A pathogen in a broad sense is anything that can produce disease. a pathogen may also ...
  34. What is Pattern formation?
    Pattern formation refers to the generation of complex organizations of the fate in space and time. ...
  35. What is Peat?
    Peat is an accumulation of partially decayed vegetation or organic matter. it is unique to natural ...
  36. What is Pedigree?
    A pedigree chart is a diagram that shows the occurrence and appearance or phenotypes of a ...
  37. What is Pepsin?
    Pepsin is an endopeptidase that breaks down proteins into smaller peptides. it is produced in the ...
  38. What is Pepsinogen?
    Pepsin's proenzyme, pepsinogen, is released by the chief cells in the stomach wall. it is released ...
  39. What is Peptide bond?
    When the carboxyl group of one amino acid reacts with the amine group of another amino ...
  40. What is Peptidoglycan?
    Peptidoglycan, also known as murein, is a polymer consisting of sugars and amino acids that forms ...
  41. What is Pericycle?
    The pericycle is a cylinder of parenchyma or sclerenchyma cells that lies just inside the endodermis ...
  42. What is Periderm?
    Periderm is a secondary protective covering that forms on small woody stems and many non-woody plants, ...
  43. What is Peristalsis?
    Peristalsis is a radially symmetrical contraction and relaxation of muscles that propagates in a wave down ...
  44. What is Peroxisome?
    Peroxisomes are cytoplasmic organelles that have an important role in catabolic reaction. these organelles contain enzymes ...
  45. What are Petals?
    Petals are modified leaves that surround the reproductive parts of flowers. they are often brightly colored ...
  46. What is PH?
    A scale of acidity to specify how basic or acidic a solution is. it is usually ...
  47. What is Phagocytosis?
    Phagocytosis is the process by which a cell uses its plasma membrane to engulf a large ...
  48. What is Pharynx?
    The pharynx is the part of the throat behind the mouth and nasal cavity, and above ...
  49. What is Phase change?
    The phase change in plants is the juvenile-to-adult transition in plants. this transition is distinct from ...
  50. What is Phenotype?
    The phenotype of an organism is the composite of the organism's observable characteristics or traits, including ...
  51. What are Pheromones?
    A pheromone is a chemical secreted or excreted by organisms that triggers a social response in ...
  52. What is Philadelphia chromosome?
    The philadelphia chromosome or philadelphia translocation (ph) is a specific genetic abnormality in chromosome 22 of ...
  53. What is Phloem sap?
    Phloem sap in plants consists primarily of sugars, hormones, and mineral elements dissolved in water. it ...
  54. What is Phloem?
    In vascular plants, phloem is the living tissue that transports the soluble organic compounds made during ...
  55. What is Phospholipid?
    This class of lipids is a major component of cell membranes of living things. these are ...
  56. What is Photomorphogenesis?
    Photomorphogenesis is light-mediated development, where plant growth patterns respond to the light spectrum. this is a ...
  57. What are Photons?
    A photon is a type of elementary particle which is basically the force carrier for the ...
  58. What is Photoperiodism?
    Photoperiodism is the physiological reaction of organisms to the length of day or night. it occurs ...
  59. What is Photorespiration?
    Photorespiration is also known as the oxidative photosynthetic carbon cycle, or c2 photosynthesis, and it refers ...
  60. What is Photosynthesis?
    Photosynthesis is a chemical reaction that takes place inside a plant, producing food for the plant ...