Question | Answer |
Antibody | a protein produced in the blood that fights diseases by attacking and killing harmful bacteria |
Antigen | a substance that causes the production of antibodies in the body |
DNA | deoxyribonucleic acid: the chemical, present at the centre of the cells of living things, that controls the structure and purpose of each cell and carries genetic information during reproduction |
Host cell | a living cell in which a virus reproduces |
Lymphocyte | a type of white blood cell involved in fighting disease and infection in the body |
Lysogenic cycle | one of two cycles of viral reproduction |
Lytic cycle | Viral reproduction. The viral DNA exists as a separate molecule within the bacterial cell, and replicates separately from the host bacterial DNA. |
Membranous envelope | All viruses lack cell membranes but some animal viruses have a membrane similar in composition to a cytoplasmic membrane surrounding their capsids called an envelope. This is a membrane envelope |
mucous membrane | A lubricating membrane lining all body passages and cavities. Examples of mucous membranes are those lining the mouth, nasal passages, vagina and urethra |
nucleic acid core | The part of a nuclear reactor where binary fission occurs. |
phagocytic white blood cell | A cell that engulfs and absorbs waste material, harmful microorganisms, or other foreign bodies in the bloodstream and tissues |
primary line of defence | a combination of physical and chemical barriers that prevent all types of foreign agents from penetrating the outer layer of the body. No specific foreign agent is targeted at this level |
protein capsid | The protein coat surrounding the nucleic acid of a virus |
RNA | ribonucleic acid, a nucleic acid present in all living cells |
secondary line of defence | White blood cells are found throughout the body and if a pathogen penetrates the first line of defence these cells play a role in inhibiting or destroying the pathogen before it harms the body. |
tertiary line of defence | f a foreign agent penetrates the non-specific barriers, there is a third line of defence available – the specific immune response. |
viral specificity | viral specificity means that a virus is selective in the organisms it infects, the type of cells and the disease it produces. |
white blood cell | Leukocyte, help fight infections by attacking bacteria, viruses, and germs that invade the body |