Structure and functions in living organisms
- Cells and organisation
- Levels of organisation
- Organelles
- Cells
- Tissues
- Organs
- Organ systems
- Animal cell
- Nucleus
- Cytoplasm
- Cell membrane
- Mitochondria
- Plant cell extras
- Cell wall
- Chloroplasts
- Vacuole
- Ribosomes make protein
- Differentiation Biology only
- Specialised cells
- Structure matches function
- Stem cells in medicine Biology only
- Replace damaged cells
- Tumour risk
- Rejection
- Ethics
- Levels of organisation
- Molecules and enzymes
- Elements
- Carbs: C H O
- Lipids: C H O
- Protein: C H O N
- Building blocks
- Sugars to starch, glycogen
- Amino acids to protein
- Fatty acids + glycerol to lipid
- Food tests
- Benedict's: glucose
- Iodine: starch
- Biuret: protein
- Ethanol: fat
- Enzymes
- Biological catalysts
- Active site
- Specific
- Temperature
- Optimum
- Denatured
- Active site shape
- pH
- Optimum pH
- Extreme pH denatures
- Amylase practicals
- Iodine in spotting tile
- Water bath
- Buffers for pH
- Elements
- Movement into and out of cells
- Diffusion
- Down concentration gradient
- Passive
- Osmosis
- Water only
- Partially permeable membrane
- Dilute to concentrated
- Active transport
- Against gradient
- Needs respiration energy
- Rate factors
- Surface area : volume
- Distance
- Temperature
- Concentration gradient
- Practicals
- Potato cylinders
- Visking tubing
- Agar cubes
- Percentage change in mass
- Diffusion
- Plant nutrition
- Photosynthesis
- light → chemical energy
- CO₂ + H₂O → glucose + O₂
- Rate
- light intensity
- CO₂ concentration
- temperature
- Leaf structure
- palisade mesophyll
- spongy mesophyll
- stomata
- transparent epidermis
- Leaf gas exchange Biology only
- thin: short distance
- flat: large surface area
- many stomata
- air spaces, moist surfaces
- Mineral ions
- magnesium: chlorophyll
- nitrate: amino acids
- Pondweed practical
- bubbles per minute
- lamp distance
- heat shield
- Starch practical
- destarch
- boil, ethanol, iodine
- foil, soda lime, variegated
- Photosynthesis
- Human nutrition
- Balanced diet
- seven components
- activity, age, pregnancy
- Nutrients
- vitamins A, C, D
- calcium, iron
- water, fibre
- Alimentary canal
- mouth to anus
- pancreas
- peristalsis
- Digestive enzymes
- amylase, maltase
- proteases
- lipases
- Bile
- liver, gall bladder
- neutralises acid
- emulsifies lipids
- Absorption
- villi, microvilli
- one cell thick
- capillaries, lacteal
- Food energy practical Biology only
- burn food under water
- mass × 4.2 × change
- Balanced diet
- Respiration
- Releases energy to make ATP
- Glucose broken down
- ADP + phosphate → ATP
- ATP provides energy
- Muscle contraction
- Active transport
- Making proteins
- Aerobic respiration
- Needs oxygen
- Glucose + oxygen → CO₂ + water
- C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O
- Anaerobic respiration
- No oxygen
- Animals: lactic acid
- Plants: ethanol + CO₂
- Aerobic releases more energy
- Practical: respiring seeds
- Heat: vacuum flasks
- CO₂: indicator or limewater
- Boiled seeds control
- Releases energy to make ATP
- Gas exchange in plants
- Waste products
- CO₂ from respiration
- O₂ from photosynthesis
- Leave by stomata
- Diffusion down gradient Biology only
- Guard cells control stomata Biology only
- Net gas exchange Biology only
- Dark: CO₂ released
- Compensation point: none
- Bright: CO₂ taken in
- Practical: indicator Biology only
- Red/orange: normal
- Yellow: more CO₂
- Purple: less CO₂
- Waste products
- Gas exchange in humans
- Thorax structures
- Ribs and intercostals
- Diaphragm
- Trachea and bronchi
- Pleural membranes
- Breathing in
- Muscles contract
- Volume up, pressure down
- Breathing out
- Muscles relax
- Volume down, pressure up
- Alveoli adaptations
- Large surface area
- Thin walls
- Good blood supply
- Moist lining
- Smoking
- Tar: cilia, cancer
- Carbon monoxide
- Nicotine
- Emphysema, CHD
- Practical: breathing
- Limewater test
- Breathing rate and exercise
- Thorax structures
- Transport in plants
- Why transport is needed
- Small SA : volume ratio
- Long diffusion distance
- Xylem
- Water and mineral ions
- Dead, lignified tubes
- Phloem
- Sucrose and amino acids
- Living cells
- Root hair cells Biology only
- Osmosis for water
- Large surface area
- Transpiration Biology only
- Evaporation from leaf
- Transpiration stream
- Factors and potometer Biology only
- Humidity, wind, temperature, light
- Bubble distance ÷ time
- Why transport is needed
- Blood and immunity
- Composition of blood
- Red and white cells
- Platelets
- Plasma
- Plasma transports
- CO₂, urea, hormones
- Digested food, heat
- Red blood cells
- Biconcave shape
- No nucleus
- Haemoglobin
- Immune response
- Phagocytes ingest
- Lymphocytes release antibodies
- Vaccination Biology only
- Memory cells
- Sooner, faster, greater
- Clotting Biology only
- Fibrinogen to fibrin
- Stops blood loss and entry
- Composition of blood
- Heart and circulation
- Heart structure
- Atria and ventricles
- Septum and valves
- Heart rate
- Increases in exercise
- Adrenaline
- Coronary heart disease
- Narrowed coronary arteries
- Risk factors
- Arteries
- Thick wall
- High pressure
- Veins
- Wide lumen
- Valves
- Capillaries
- One cell thick
- Exchange
- Circulation system
- Double circulation
- Liver and kidney vessels
- Heart structure
- Excretion
- Organs of excretion
- Lungs: carbon dioxide
- Skin: water, salts, urea
- Kidneys: urea in urine
- Urinary system Biology only
- Kidney
- Ureter
- Bladder
- Urethra
- Nephron structure Biology only
- Bowman's capsule, glomerulus
- Convoluted tubules
- Loop of Henle
- Collecting duct
- Ultrafiltration Biology only
- High pressure
- Small molecules pass
- Proteins stay in blood
- Selective reabsorption Biology only
- Glucose at proximal tubule
- Active transport
- Water by osmosis at collecting duct
- Urine contents Biology only
- Water
- Urea
- Ions
- ADH Biology only
- Pituitary gland
- Collecting duct permeability
- Water content of blood
- Organs of excretion
- Coordination and plants
- Responding to change
- Stimulus
- Receptor
- Effector
- Animal and plant responses
- Nervous system
- Hormones
- Plant growth
- Homeostasis
- Constant internal environment
- Body water content
- Body temperature
- Tropisms
- Phototropism
- Geotropism
- Shoots and roots
- Shoot: towards light, up
- Root: away from light, down
- Auxin
- Made in shoot tip
- Moves to shaded side
- Cells elongate
- Responding to change
- Nervous system and eye
- CNS
- Brain
- Spinal cord
- Nerves link sense organs
- Synapse
- Neurotransmitter
- Diffuses across gap
- Binds to receptors
- Reflex arc
- Receptor
- Sensory neurone
- Relay neurone
- Motor neurone
- Eye structure
- Cornea refracts
- Lens focuses
- Retina: rods and cones
- Optic nerve
- Focusing
- Near: lens thicker
- Distant: lens thinner
- Ciliary muscles
- Pupil reflex
- Bright: circular contract
- Dim: radial contract
- CNS
- Hormones and temperature
- Nervous vs hormonal
- Impulses vs blood
- Fast vs slower
- Short vs longer
- Adrenaline
- Adrenal glands
- Fight or flight
- Heart rate up
- Insulin
- Pancreas
- Glucose to glycogen
- Sex hormones
- Testosterone: testes
- Oestrogen: ovaries
- Progesterone: ovaries
- ADH, FSH, LH Biology only
- Pituitary gland
- ADH: water reabsorbed
- FSH: egg matures
- LH: ovulation
- Skin
- Sweating
- Vasodilation
- Vasoconstriction
- Nervous vs hormonal