Question

please fill out the definitions of each term:

51. Latency

52. Lectin

53. Leukocytes

54. Memory cell

55. Major histocompatability complex (MHC)

56. Monoclonal antibody

57. Myeloid cells

58. Negative selection

59. Opsonin

60. PAMP

61. Parafollicular boundary

62. Pathogen

63. Pathogenicity

64. Pattern recognition receptors (PRRs)

65. Phagocyte

66. Plasma cell

67. Polyclonal antibody

68. Positive selection

69. Primary lymphoid tissues

70. Primary response

71. Professional APCs

72. Secondary lymphoid tissue

73. Secondary response

74. Soluble defensive factors

75. Somatic recombination

76. Stem cell

77. T cell independent (TI) B cell Ag

78. T cell dependent (TD) B cell Ag

79. T cell receptor (TCR)

80. Thymic education

81. Thymocyte

82. Tolerance (central, peripheral and other)

83. Vaccine

84. Vector

85. Virulence

86. Zoonosis

Answer 1

51. Latency- it is a period in which the infection is present in the host but does not produce any openly symptoms.

52. Lectin- Lectins are carbohydrate-binding proteins which help in recognition on the cellular and molecular level and play important roles in biological recognition mechanisms.

53. Leukocytes- White blood cells (WBCs), or leucocytes, are the cells of the immune system which are involved in protecting the body against infectious disease and plays an important role in immune response.

54. Memory cell- long-lived lymphocyte that has previously encountered a particular antigen and on re-exposure to the same antigen initiates the immune response or proliferates and produces large amounts of specific antibody rapidly.

55. Major histocompatability complex (MHC)- group of genes that that help the immune system recognize foreign substances and plays important role in histocompatibility reactions.

56. Monoclonal antibody- antibodies which can bind to a particular one epitope only.

57. Myeloid cells- These are the precursors of granulocytes, macrophages, dendritic cells, and mast cells of the immune system.

58. Negative selection- Negative selection refers to the selective removal of rare alleles that are deleterious.

59. Opsonin- An opsonin is any molecule that enhances phagocytosis by making an antigen more attractive for a phagocyte

60. PAMP- Pathogen-associated molecular patterns are molecules associated with groups of pathogens, (conserved within a class of microbes) and are recognized by cells of the innate immune system.

61. Parafollicular boundary- Parafollicular cells are neuroendocrine cells in the thyroid whose primary function is to secrete calcitonin.

62. Pathogen- any disease causing agents

63. Pathogenicity- Pathogenicity is the disease-causing capacity of pathogens.

64. Pattern recognition receptors (PRRs)- in order to detect pathogens the immune system cells contain receptors that are specialised in their recognition of pathogens.

65. Phagocyte- cells that protect the body from harmful foreign particles, bacteria, and dead or dying cells.

66. Plasma cell- Plasma cells, are white blood cells that can secrete large volumes of antibodies.

67. Polyclonal antibody- antibodies which can bind to multiple epitopes only.

68. Positive selection- the isolation of a target cell population by using an antibody that can specifically binds to that population.

69. Primary lymphoid tissues- tissues of an organism where lymphocytes are formed and mature

70. Primary response- The  immune response which occurs when an antigen comes for the first time encounters the immune system

71. Professional APCs- specialized antigen presenting cells which helps in presenting antigen to T cells

72. Secondary lymphoid tissue- Secondary lymphoid organs, include lymph nodes and the spleen, which maintain mature naive lymphocytes.

73. Secondary response- more heightened response in individuals encountered with same antigen

74. Soluble defensive factors- Soluble factors in blood plasma are the factors which have an impact on both the innate and adaptive immune responses. Eg:- The complement system, antibodies

75. Somatic recombination- Somatic recombination, is an alteration of the DNA of a somatic cell which gets inherited into the next generation

76. Stem cell- a class of undifferentiated cells having the ability to differentiate into specialized cell types in the adults.

77. T cell independent (TI) B cell Ag- independent antigen which can elicit antibody production by B lymphocytes without any involvement of T lymphocyte.

78. T cell dependent (TD) B cell Ag- dependent antigen which cannot elicit antibody production by B lymphocytes without any involvement of T lymphocyte.

79. T cell receptor (TCR)- The T-cell receptor is a molecule found on the surface of T cells, and is responsible for recognizing antigen as peptides bound to major histocompatibility complex molecules

80. Thymic education- The phenomenon of positive selection of developing T cells in the thymus.

81. Thymocyte- The thymocytes are cells whose primary function is to generate T lymphocytes.

82. Tolerance (central, peripheral and other)- Immunological tolerance refers to the failure of immune system to mount an immune response to an antigen.

83. Vaccine- any antigenic preparation which can stimulate the immune system against the microbe, thereby prevent disease.

84. Vector- any agent which have the ability to transfer diseases to different organisms

85. Virulence- The ability of a pathogenic organism to cause disease

86. Zoonosis- infectious diseases of animals that can naturally be transmitted to humans