Flashcards
Biology Topic 6 Flashcards
Flashcards do conjunto (45)
- 1What are the 5 stages of decomposition?Fresh
Bloat
Active
Advanced
Dry/remains - 2What are the characteristics of putrefaction?Blisters appear on the skin.
Green discolouration of the abdomen.
Gases produced. - 3What happens during autolysis?A body's own enzymes from lysosomes break down body tissues. Loss of oxygen from tissues encourages growth of anaerobic bacteria.
- 4List 4 factors which affect rate of decompositionTemp.
Body size .
Conditions.
Circumstances (e.g. submerged).
Activity before death. - 5What is the order of types of orgs. attracted to a cadavar during decomposition?1. Anaerobic bacteria - colonisers
2. Blow flies and other flies
3. Parasitic wasps
4. Beetles
5. Carcass and ham beetles
6. Hair mites and moss larvae - 6Describe the stages of rigour1. Muscles starved of oxygen and O-dep. reactions stop.
2. Respiration continues anaerobically.
3. Lactic acid is produced and pH drops.
4. Enzymes producing ATP and inhibited.
5. The lack of ATP means bonds between myosin + actin become fixed meaning muscles cannot contract or relax.
6. The body stiffens. - 7Describe the role of microorgs.Bacteria and fungi produce enzymes released onto dead organisms and absorb the product of their external digestion. It is broken down in microbial respiration and CO2 is released. This recycles the carbon, helping to maintain the carbon cycle.
- 8What type of enzymes can be used in gel electrophoresis to produced fragments from a section of DNA?Restriction endonucleases.
- 9List 5 structures found on a virusReceptors
Nucleic acid
Capsid
Capsomere
Envelope - 10List 9 structures found in a bacteriumCapsule
Mesosome
Ribosomes
Cell surface membrane
Pilus
Circular DNA
Cell wall
Plasmids
Flagella - 11Describe a gram -ve bacterial cell wallThin layer of peptidoglycan between 2 layers of plasma membrane.
- 12Describe a gram +ve bacterial cell wallA thick layer of peptidoglycan with teichoic acid and 1 plasma membrane on the inside.
- 13What are the 3 stages of HIV?Acute Phase
Chronic Phase
Disease Phase - 14In which phase of HIV does AIDS onset?Disease phase
- 15What are the symptoms of active TB?Coughing
Shortness of breath
Loss of appetite
Fever
Extreme fatigue - 16What copies viral RNA into viral DNA?Reverse transcriptase
- 17What inserts viral DNA into host DNA?Integrase
- 18List 4 non-specific immune response mechanismsInflammation
Lysozyme action
Phagocytosis
Interferons - 19What are 2 types of phagocytes?Neutrophils + Macrophages
- 20What do interferons prevent?Viruses spreading to uninfected cells.
- 21What does MHC stand for?Major Histocompatibility (protein)
- 22What do antibodies do?Agglutinate pathogens (cause clumping).
Block cell surface receptors of pathogens reducing their ability to bind to host cells.
The anti-b/anti-g complex marks it up for digestion by phagocytes.
Neutralises toxins. - 23Which type of the specific immune response are T killer cells involved in?Cell mediated response
- 24Which type of specific immune response are B cells involved in?Humoral response
- 25What does non-overlapping, degenerate triplet code mean?It is read as a sequence of 3 bases where no base of one triplet forms part of the next. There are 64 possible triplet combinations and not as many AA's therefore it contains more info than needed and is redundant.
- 26Which is the coding region: introns or exons?Exons
- 27By which process are introns removed?mRNA splicing
- 28What are 2 post-transcriptional changes other than mRNA splicing?Addition of a poly A tail and a guanine cap.
- 29List 6 ways pathogens can be transmitted1. Vectors
2. Formites (inanimate objects)
3. Direct contact
4. Inhalation
5. Ingestion
6. Inoculation - 30What are 4 barriers to pathogens on the human body?Skin
Mucous membranes
Stomach acid
Gut flora - 31Define: Active immunityWhen your immune system makes its own antibodies after being stimulated by an antigen.
- 32How do you gain active natural immunity?By catching a disease and fighting it so that you become immune.
- 33What type of immunity do vaccines give you?Active artificial
- 34Define: Passive immunityThe type you get from being given antibodies from a different organism.
- 35Give an example of natural passive immunityWhen pre-formed antibodies are passed on from mother to foetus during pregnancy and in breast milk.
- 36Define: vaccineThe process by which you immunise people to produce immunity.
- 37List 3 pros of vaccinationsThe child is protected from potentially lethal diseases.
Society benefits from a reduced pool of infection and helps to form herd immunity.
Vaccines are cheap compared to cost of treating diseases. - 38List 4 cons of vaccinationsSome live viruses are cultured from eggs and can cause an allergic response.
A small % of people have an extreme immune response and can die.
Mass vaccination has been linked to a rise in childhood asthma and allergies.
Some vaccines are given more for the benefit of society that for the benefit of the child. - 39What are 3 evasion mechanisms of HIV1. It replicates inside T cells so viral particles are enveloped in host cell surface receptors.
2. It has a high mutation rate in genes coding for antigen proteins causing antigen variation.
3. It disrupts antigen presentation in infected cells. - 40Which receptors are on the surface of HIV?gp120
- 41How does TB evade the immune system?It produces a thick waxy outer layer preventing lysosomes fusing with the phagocytic vesicle and allowing it to multiply undetected inside macrophages and remain dormant for years.
- 42The 2 types of antibiotic are...Bactericidal & Bacteriostatic
- 43What is the difference between a broad spectrum and a narrow spectrum antibiotic?Broad spectrum antibiotics destroy a wider range of bacteria which may be harmful or beneficial where as narrow spectrum antibiotics target 1 or 2 specific pathogens.
- 44Changes in hospital codes of practiceSparing antibiotic use which is more selective
Completion of treatment necessary
Better hygiene
Isolation of patients
Screening incoming patients
Advising against ill visitors
Monitoring levels of HAI's - 45What does HAI stand for?Hospital Acquired Infection
Informações
- Descrição
- A2 level Biology FlashCards sobre Biology Topic 6 Flashcards, criado por J000D97 em 15-01-2015.
- Criado por
- J000D97
- Visualizações
- 175
- Tags
- Avaliação