B1 B2 B3

B1 B2 B3

Nucleus contains genetic material
1. Arranged into chromosomes (moles of DNA)
  1. Gene short length chromosome // diff. versions of same called ALLELLE
    1. Code for making proteins - diff characteristic.
      1. STRUCTURAL - skin, hair, blood
      2. FUNCTIONAL - digestive enzymes (amalyse)
    2. GENOTYPE - genes it has PHENOTYPE - expressed
      1. HOMOZYGOUS - Two same allele HETEROZYGOUS - Two diff allele
        DOMINANT
        RECESSIVE
  2. Sex cells - 23 chromosome // from parents
    1. Men - XY Chromsome
      1. Testes // Testosterone
    2. Women - XX Chromosome
      1. Ovaries // Oestrogen
Genetic disorders caused by faulty alleles
1. CYSTIC FIBROSIS // Recessive Alleles
  1. Respiratory probs // thick sticky mucus // chest infections // difficult digestion
  2. 1 in 25 Carriers
  3. carrier or sufferer
2. HUNTINGDON'S // Dominant Alleles
  1. Tremors // Memory loss // Poor concentration // Mood change
  2. 50% chance
  3. late onset
3. Genetic Testing - embryo // children // adults
  1. Pre-implantation genetic disorder
  2. carry alleles for genetic disorders
  3. not 100% accurate // misinterpreted or contaminated
  4. not 100% safe // cause miscarriage
  5. positive // all family tested? // false negative positive
  6. terminate pregnancy // financial // coping // right to life
  7. discrimination // employers // insurance
Clones are genetically identical organisms
1. Asexual
2. Embryo split
3. Artificial
Stems Cells - UNSPECIALISED
1. EMBRYONIC - any cell
  1. muscle cells // insulin producing // nerves
2. ADULT - maintain repair old damage tissue
  1. bone marrow transplant
    1. sickle cell anaemia
Symptoms are caused by cell damage or toxins
1. Microorganisms reproduce quickly inside body (warm moist conditions)
  1. Calculate grown of pop.
    1. Number at start
    2. how long it takes to reproduce
    3. how long left to reproduce
  2. Immune system fights off invading microbes
    1. white blood cell detect 'foreign' // engulf & digest
      1. antibodies specific to antigen
        mark - other W.B.C
        bind and neutralise
        kill directly
        memory cells stay around
  3. Vaccination safe version of microorganism
    1. Immunisation - dead / inactive antigens - memory cells
      1. Epidemics prevented by vaccination
        Side effects // Genetic diff - react diff
    2. Antimicrobials inhibit of kill bacteria, fungi and viruses
      1. M.O evolve - RESISTANT - mutation in DNA
        Reproduce - gene pass on // more common
      2. Drugs tested in lab
        Human cells
        Live mammal
        human volunteer
        Healthy - safe
        PLACEBO
        BLIND TRIAL
        DOUBLE BLIND TRIAL
        OPEN LABEL TRIAL
Heart & blood cells supply blood to body
1. HEART // Right - deoxygenated to lungs // Left - oxygenated to body
  1. Blood supplied to heart from coronary arteries from aorta
    1. ARTERIES - blood away from heart // high pressure - strong elastic walls
    2. VEINS - blood to heart // low pressure - lumen and valves
    3. CAPILLARIES - exchange substance in blood // diffusion
    4. Pulse rate measure BPM
      1. DIASTOLIC - contract // SYSTOLIC - relax
        H.B.P increase risk of heart disease
        Fatty deposit restrict blood flow
        Blood clot form
        Coronary blocked no oxygen - heart attack
        Poor Diet - high cholesterol / salt
        Smoking - CO reduce O2 // Nicotine increase H.R
        Stress
        Drugs & Alcohol
HOMEOSTATIS - maintaining constant internal environment
1. Negative feedback counteracts change
  1. ADH secreted from pituitary gland
    1. Water - too high // less ADH // kidneys reabsorb less // more urine - dilute.
    2. Water - too low // more ADH // kidneys reabsorb more // less urine - high conc.
    3. Alcohol suppress - dehydration
    4. Ecstasy increase
A species is a group of organisms that can breed together to produce fertile offspring
1. Adapt to survive
  1. Cacti - wax and spines // reduce water loss
  2. Fish - gills // streamline // swim bladder
  3. Natural selection - "Survival of the Fittest"
    1. Competition // passed on
    2. Rabbits
    3. Selective Breeding - desired features
      1. Cows
2. Life on Earth - 3500 million y.a.
  1. Evolution - new species
    1. Isolated // mutation // natural sel. // enivro
      1. Charles Darwin Theory of Evolution
      2. Lamarck - chara used lots - more developed
    2. Biodiversity
      1. Number of species
      2. Genetic variation
      3. Range of different types
      4. KINGDOMS - bacteria, fungi, plant, algae, plants, animals
      5. Interdependence - pop. inc / dec.
        EXTINCTION - enviro. change // competition // disease // food web
      6. Energy in Ecosystems
        Sun - main source // photosynthesis - convert
        Transfer - consumption // decay - dead n waste
        Lost - respiration // heat (const. temp) // waste products
        efficiency = energy available / energy was available x 100
        CO2 powers photosynthesis
        CO2 into glucose
        eating passes compounds in food chain
        Respiration releases CO2
        Die n decompose - release CO2 from decomposers respiring
        Combustion release CO2
Nitrogen need for growth proteins
1. Fixation - N2 into nitrates
  1. Lightning
  2. Fixing bacteria
  3. Decomposer - proteins & urea to ammonia
    1. Nitrifying - ammonia into nitrates
      1. Denitrifying - nitrate to N2
Enviro. Change
1. Temp - Climate
2. Nitrate - Water
3. CO2 - Air
4. Air - Lichen // SO4 - no. - clean
  1. Water - Mayfly // O2 - no.- clean
    1. Water - Phytoplankton // Algal bloom
5. SUSTAINABILITY - meeting demands of today without harming enviro so future gens. can meet theirs
  1. Renewable materials
  2. Less energy
  3. Less pollution

Next up

Description

Resource summary

Similar

	Created by Lauren Healey almost 10 years ago