Common Task 2 Revision (Stem cells (Ethical concerns?, Unspecialised cell…
Common Task 2
Health & Disease
lymphocytes release antibodies in response to antigens
weakened form of pathogen
memory lymphocytes release antibodies in the future when a new infection occurs-secondary response
Physical barriers to pathogens?
Chemical barriers to pathogens?
What is an STI/ Give two examples
sexually transmitted infection e.g. chlamydia, HIV- condoms protect us, screening identifies
What is a vector?
Organism that carries pathogens from one organism to another e.g. mosquito
Ways pathogens spread?
Types of pathogens:
lesions on bark
watery faeces, diarrhoea
Types of neurones
Unspecialised cell-can become any cell
Issues with stem cells?
Can divide often by mitosis and differentiate
Uses of stem cells?
Embryonic stem cells can differentiate and specialise into any kind of cell
Uncontrolled cell division -cancer
Adult stem cells can only become one type of tissue
Change in DNA can cause uncontrolled cell division
Plant stem cells are found in meristems in roots and cambium in stems