Zusammenfassung der Ressource
Biology B2
- Balancing water
- correct level for cell activity
- kidneys help balance substances in the body
- filter out small molecules like water, sugar, salt and waste
- reabsorb various things
- whatever isn't is then made urine which is excreted by bladder
- Heart and circulatory
- Arteries
- Carry blood away from the heart to body cells
- High pressure so thick, strong and elastic walls are used
- Veins
- Carry blood back to the heart
- Lower pressure so thinner walls
- Bigger lumen to help blood flow more easily
- Capillaries
- carry blood really close to every cell
- thin wall so substances can diffuse in and out
- very small lumen
- Drug Trials
- Tested in a lab (1st)
- Tested on human cells
- cannot recreate the conditions of a human body
- Tested on live mammals to check for harmful substances
- stopped if drug fails or is too harmful
- tested on humans (2nd)
- tested on healthy people first to check for side effects
- Placebos are used (fake drugs)
- blind trials, double-blind and open-label trials
- Antimicrobials
- chemicals that inhibit the growth of microrganisms or kill them
- EG - Antibiotics/Penicillin
- important to finish entire course
- increases risk of antibiotic resistance bacteria coming back
- Microorgasnisms can become resitant (they evolve)
- random mutation in their DNA
- Diseases
- Bacteria, Virus and Fungi
- Reproduces quickly - making copies of themselves
- Need warm, moist conditions like intestines and nutrients
- Need other cells to reproduce
- Makes copies of themselves
- Immune System
- White Blood Cells
- Located the foreign microorganism
- Digests it and then memories it in case it comes back
- White blood cell divides to produce more antigens so it can fight the infection
- Antibodies help locate the foreign cell and mark it
- Vaccinations
- Injecting a dead or inactive microorganism
- Body can produce antibodies to attack them and create antigens (memory cells)
- If it appears again, the body can fight it off quicker
- Less chance of epidemics spreading if more of the population is vaccinated