AQA A Level Biology复习笔记2.5.9 Antigen-Antibody Complex
Antigen-Antibody Complex An?antigen?and its complementary?antibody?have?complementary?molecular shapes This means that their molecular structures?fit into each other When an antibody?...
AQA A Level Biology复习笔记2.5.8 Antibodies
Antibodies: Structure Structure Antibodies are?globular glycoproteins?called?immunoglobulins Antibodies have a?quaternary?structure (which is represented as?Y-shaped), with?two ‘heavy’?(long...
AQA A Level Biology复习笔记2.5.7 The B lymphocyte Response
The B lymphocyte Response B-lymphocytes and the humoral immune response B-lymphocytes?(B cells) remain in the?bone marrow?until they are?mature?and then spread through the body, concentratin...
AQA A Level Biology复习笔记2.5.6 The Role of Helper T cells
The Role of Helper T cells Activated T-lymphocytes (those that have receptors specific to an antigen)?divide?by?mitosis?to increase in number (similar to the?clonal selection and clonal expa...
AQA A Level Biology复习笔记2.5.5 The Role of Antigen-Presenting Cells
The Role of Antigen-Presenting Cells T-lymphocytes produce an immune response when they are exposed to a specific antigen T cells will only bind to an antigen if it is present on the surface...
AQA A Level Biology复习笔记2.5.4 The T Lymphocyte Response
The T Lymphocyte Response Lymphocytes?are another type of white blood cell They play an important part in the?specific?immune response They are?smaller?than phagocytes They have a?large nucl...
AQA A Level Biology复习笔记2.5.3 Phagocytosis
Phagocytosis Phagocytes are white blood cells that are produced continuously in the?bone marrow They are stored in the bone marrow before being?distributed around the body in the blood They ...
AQA A Level Biology复习笔记2.5.2 Antigens
Antigens Every cell in the human body has?markers?that?identify?it Microorganisms (both pathogenic and non-pathogenic), such as bacteria and viruses, also have their own unique markers These...
AQA A Level Biology复习笔记2.4.13 Factors Affecting Membrane Fluidity
Required Practical: Factors Affecting Membrane Permeability The?permeability?of?cell membranes?is affected by different?factors?or conditions, such as: Temperature Solvent concentration &nbs...
