GCSE Biology Exam 2

1. Techniques

   Nota:

   • Quadrats Transect lines Nets Pooters Pitfall traps
2. Be reliable
3. Be fair
4. Capture-recapture collection

Nota:

• 6CO2+6H2O=>C6H12O6+O2

1. 2 stages
2. Creates Glucose
   1. Starch
   2. Amino Acids
   3. Sucrose
3. Oxygen waste
4. Differing rates
   1. Limiting factors
   2. Add more of the reactants
   3. Higher temperature
5. Different lights absorbed

1. Leaf structure
   1. Different layers of cells

      Nota:

      • Waxy Cuticle Upper Epidermis Palisade Mesophyl layer  Spongy Mesophyl layer Lower Epidermis (has guards cells and stomata inside it)
   2. Carries out Photosynthesis
   3. Physical structures

      Nota:

      • Leaf Blade Mid-Rib Side Veins Leaf stalk
2. Xylem
   1. Transports water and dissolved minerals
3. Phloem
   1. Transports food substances

      Nota:

      • Phloem-phood (food)

1. Diffusion

   Nota:

   • Movement of minerals down a concentration gradient
2. Osmosis

   Nota:

   • Movement of water down a concentration gradient
   1. In animal cells

      Nota:

      • Too much water and cells may swell and burst, called a lysis Too little and the cells will become crenated (crinkled)
   2. In plant cells

      Nota:

      • Too much and the cell swells and becomes turgid (firm) Too little and the cell becomes flaccid (soft before becoming plasmolysed)
3. Factors that affect Osmosis and Diffusion

   Nota:

   • Distance travelled (width of cell membrane) Concentration gradient (more means more diffusion/osmosis) Surface area (more means more diffusion/Osmosis

1. Increasing the rate of transpiration
   1. High light intensity
   2. Increase in temperature
   3. Increase in air movement
   4. Decreased humidity
2. Minerals
   1. Nitrates
   2. Phosphates
   3. Potassium
   4. Magnesium

1. Detritivores

   Nota:

   • Creatures like earthworms eat detritus (dead leaves) and are called detritivores
2. Decomposers

   Nota:

   • Bacteria and funghi decompose dead stuff
3. Changing the rate of decay
   1. Increasing temperatures
   2. Increasng the amount of water
   3. Increasing the amount of oxygen

1. Intensive farming
   1. Advantages

      Nota:

      • Higher yields gives higher profits Low production costs leads to higher profits Less labour intensive leads to lower production costs and more profit
   2. Disadvantages

      Nota:

      • Excessive use of fertilisers can cause pollution and eutrophication Excessive use of pesticides can damage the ecosystem Battery rearing of animals is inhumane
2. Futuristic farming
   1. Fish farming
      1. Advantages

         Nota:

         • Large stock are easy to catch It is cheaper Less predation of stock Less need to fish wild stock
      2. Disadvantages

         Nota:

         • Disease spreads quickly
   2. Hydroponics
   3. Glasshouses

      Nota:

      • Energy efficient Environment is manipulatable Diseases are controllable Pesticides and fertilisers are contained Glasshouses can be used all over the country so we don't have to import as much
3. Organic farming
   1. More labour intensive
   2. Biological control can go wrong (Australia)
   3. Adding animals to the food web alters it massively

1. Skeletons
   1. Internal
      1. Positives
         1. Grows with the body
      2. Negatives
         1. Less protection
   2. External
      1. Positives
         1. Extra protection
      2. Negatives
         1. Does not grow with the body
   3. Bone fractures
      1. Green stick

         Nota:

         • Bone bends but does not break
      2. Simple

         Nota:

         • Bone breaks but does not pierce the skin
      3. Compound

         Nota:

         • Bone breaks and pierces the skin
2. Muscles
   1. How the arm works

      Nota:

      • When you bend the arm: Your biceps contract and your triceps relax The tendons don't stretch Radius pulled up and arm bends Opposite for straightening
3. Joints
   1. Fixed
   2. Hinged
   3. Ball & Socket

1. Circulatory
   1. Single celled organisms

      Nota:

      • Don't need a circulatory system Absorb all required minerals through their cell membranes
   2. Open system

      Nota:

      • Blood is outside blood vessels and bathes organs in blood
   3. Closed system

      Nota:

      • Blood stays inside vessels at all times
      1. Single circulation

         Nota:

         • Used by fish Blood goes through the heart once for every circulation of the body
      2. Doubled circulation

         Nota:

         • Used in humans Blood goes through heart twice for every circulation of the body
2. Cardiac
   1. Blood donation
      1. Blood Types
         1. A

            Nota:

            • Type A antigens Anti B Antibodies
         2. B

            Nota:

            • Type B Antigens Anti A Antibodies
         3. AB

            Nota:

            • Type A and Type B antigens No antibodies
         4. O

            Nota:

            • No antigens Anti A and Anti B antibodies
   2. Heart repairs
3. Respiratory
   1. Gaseous exchange
   2. human respiratory system
      1. Diseases

         Nota:

         • Bronchitis Asbestos Cystic Fibrosis Lung Cancer Asthma
4. Digestive
   1. Chemical Digestion
      1. Enzymes
         1. Carbohydrase
         2. Lipase
         3. Protease
   2. Small intestines

      Nota:

      • Adaptations: Very long Large surface area Thin lining Good blood supply
5. Excretion

1. Sex characteristics
   1. Male
      1. Voice deepens
      2. Hair grows on the face and body
      3. Body becomes more muscular
      4. Genitals develop
      5. Testes make sperm
   2. Female
      1. Breasts develop
      2. Pubic hair grows under the arms
      3. Hips widen
      4. Menstruation starts
         1. Menstrual cycle

            Nota:

            • Pituitary glands release FSH FSH causes an egg in one of the ovaries to mature Ovaries make oestrogen Oestrogen makes the brain release LH in the pituitary gland LH triggers ovulation Oestrogen stops the further production of FSH and repairs the uterus lining  Progesterone maintains the uterus lining and inhibits LH
2. Fertility and fetal screening
   1. Fertility
      1. Increasing

         Nota:

         • Vitro fertilisation Artificial insemination Egg donation Surrogacy (Ovary transplants)
      2. Decreasing

         Nota:

         • Contraceptive pills
3. Growth

1. Bacteria
   1. Example disease
      1. Cholera
   2. Reproduce via binary fission
   3. Cell facts
      1. No nucleus
         1. Nucleoid
      2. Cell wall
      3. Flagellum
2. Funghi
   1. Yeast
      1. Reproduce by budding
      2. Does fermentation
         1. Beer :)
            1. Distillation
               1. Whisky :D
   2. Example disease
      1. Athletes' foot
   3. Reproduce via binary fission
   4. Cell facts
      1. Inside can be found
         1. A nucleus
         2. Vacuoles
3. Viruses
   1. Dangerous
   2. Very Small
   3. Parasitic
      1. Takes over cell functions
         1. Forces the cell to
            1. create new
               1. viruses
   4. Example Diseases
      1. Common Cold
      2. Influenza
   5. Cell facts
      1. Loop of DNA surrounded by a protein coat
4. Fighting them
   1. Louis Pasteur

      Nota:

      • French Proved that decay was down to microorganisms in the air Created the germ theory

      Adjunto:

      • Louis Pasteur
   2. Joseph Lister

      Nota:

      • Developed antiseptics Killed microbes Reduced the number of postoperative infections

      Adjunto:

      • Joseph Lister
   3. Sir Alexander Flemming

      Nota:

      • Discovered Penicillin Made the first antibiotics from this fungus

1. Plants
   1. More Yield
   2. Pest resistance
   3. Controversial

1. In Soil
   1. Soil types
      1. Clay
         1. Small particles
            1. Few air spaces
            2. Low water permeability
      2. Loam (mixture)
      3. Sand
         1. Big particles
            1. Large air spaces
            2. Low water retention
   2. Example creatures
      1. Earthworms
         1. Pull down dead leaves
         2. Create gaps to aerate the soil
         3. Release calcium carbonate
      2. Spiders
2. In Water
   1. Advantages
      1. Bouyancy
      2. Removal of waste
      3. Steady temperature
   2. Disadvantages
      1. Movement difficulties
      2. Osmotic balance
   3. Example creatures
      1. Wahles
      2. Plankton
         1. Phytoplankton
         2. Zooplankton