Biology B1

1
Biology B1

• Fit for Life
• Blood pressure unit is mmHg and consists of
  Diastolic and Systolic.
• Fitness is physical activity and Health is free
  from infection
• Respiration can be aerobic (with O2) or anaerobic
  (without O2)

• Whats for lunch?
• Carbohydratessugar/glucose Fats
  fatty acids and glycerol
  Proteins amino acids
• Enzymes digest specific food molecules
• Small food molecules are absorbed into the blood
  in the small intestine

Glucose oxygen ? carbon dioxide water
C6H12O6 6O2 ? 6CO2 6H2O
2

• Keeping in touch
• Receptors skin pressure, temperature and
  pain, eyes light, Ears sound and
  balance, Nose and tongue chemical
• Retinacontains light receptors, Lensfocuses
  light on retina, Iriscontrols amount of light
  going into the eye
  Optic nerveimpulse to brain
• Accommodation long (convex) short sight
  (concave)
• Reflex fast, automatic and protective how
  neurones adapted
• Stimulus-receptor-sensory neurone-CNS-motor
  neurone-effector-response

• Keeping Healthy
• Defences are skin, blood clots, stomach acid
  and mucus
• Vectors carry and spread disease e.g mosquitoes
• Parasites cause disease e.g malaria protozoa,
  bacteria, fungi and viruses
• Pathogens have antigens we make antibodies which
  lock on to the antigen and kill the pathogen
• Antibiotics kill fungal and bacterial infections
• Other diseases are due to diet, genetics or body
  disorders(tumours benign/malignant, diabetes)

3

• Drugs and you
• Categories Depressants, Stimulants, Pain
  killers, Performance enhancers, Hallucinogens
• Class A C (most dangerous - least dangerous,
  lightest penalties)
• Smoking Lung cancer, Emphysema, heart disease
  (CO) , birth weight, no cilia
• Alcohol Liver Cirrhosis, reaction times car
  accidents

• Staying in balance
• Homeostasis Maintenance of a constant internal
  environment
• Temperature 370C
• Hormones Oestrogenthickens uterus wall,
  Progesteronemaintains uterus wall - used in the
  pill
• Insulin controls blood sugar levels lack of
  diabetes

4

• Gene Control
• 46 chromosomes in humans (23 pairs)
• Chromosomes DNA genes
• Bases A-T C-G
• Genes are switched on or off
• Gametes have half the number, come together to
  give genetic variation

• Who am I?
• XX female, XY male
• Genetic variation mutations, fertilisation,
  gamete formation
• Allele different type of same gene
• Heterozygous Aa, Homozygous recessive aa,
  Homozygous dominant AA
• Inherited disorders faulty alleles (recessive)
• Mutations change DNA base sequence changes the
  protein the DNA codes for, caused by
  radiation/chemicals

5
Chemistry C1

• Atomic structure
• Atoms are made up of protons neutrons and
  electrons
• Protons have a mass of 1 and a charge of 1.
• Electrons have a very small mass and a charge of
  -1.
• Neutrons have no charge and a mass of 1.
• Protons and neutrons are in the nucleus.

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Bonding

• There are two kinds of bonding, ionic and
  covalent.
• In ionic bonding electrons are donated and
  received and charged ions are formed.
• Ionic substances are high melting point solids
  which conduct electricity when molten or
  dissolved in water.
• Covalent substances share electrons, forming
  molecules.

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Alkanes and alkenes

• Alkanes include methane CH4 ,and ethane C2H6
  .They have the general formula CnH2n2 .
• Alkenes include ethene C2H4. They all have one
  double bond and decolourise bromine water. They
  have the general formula CnH2n .
• Alkanes and alkenes are hydrocarbons because they
  are compounds containing carbon and hydrogen
  only.
• Alkenes can be made into polymers with high
  pressure and a catalyst.

8
Measuring energy in fuels

• To measure energy in fuels water can be heated in
  a calorimeter or flask.
• Heat mass water x s.h.c .x temp. rise
• Energy per gram Heat / mass of fuel
• The mass of water used is usually 100g.
• Usually- Heat 100 x 4.18 x temp. rise
• Check these calculations

9
Perfumes and cooking

• Perfumes can be made from natural products such
  as roses and lavender.
• Artificial fragrences are made from esters.
• Esters are made by reacting an acid and an
  alcohol with conc. Sulphuric acid as catalyst
• Perfumes must evaporate easily,be non toxic,
  insoluble in water and a non irritant.
• Food must be cooked for various reasons, to make
  meat more tender break down cellulose in potatoes
  to release starch, kill bacteria, improve
  flavour.
• Baking powder is used in self raising flour
  because carbon dioxide is released on heating.

10
Crude oil

• Crude oil was formed millions of years ago when
  animals in the sea died, became covered with
  sediment, and were compressed.
• Crude oil can be separated into fractions by
  fractional distillation.
• Each fraction has a different boiling point,
• Large molecules like bitumen have high boiling
  points because the molecules are large.
• Crude oil can undergo cracking by heating with a
  catalyst. More useful fractions like petrol can
  be made from less useful ones like fuel oil.

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Physics P1 Energy for the home

• Basics
• Energy always flows from a warmer body to a
  cooler body.
• Heat is a form of energy (measured in Joules)
• Temperature is a measure of how much heat an
  object has (measured in C)
• Measuring Temperature Thermometer
  Thermocouple Resistance thermometers
  Thermograms.

12
Insulation
All these trap air TRAPPED AIR IS A POOR
CONDUCTOR OF HEAT

• Cavity Wall Insulation
• Loft Insulation
• Double Glazing
• Draught excluders
• Silver foil behind radiators

SILVER FOIL REFLECTS RADIATED HEAT BACK INTO THE
ROOM
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Specific Heat Capacity Specific Latent Heat
SHC is the heat needed to raise the temperature
of 1kg of a substance by 1Celsius. Q m x c x
?? Can you change the subject of this equation?
SLH is the heat needed to change the state of 1kg
of a substance Q m x l Can you change the
subject of this equation?
14
The Electromagnetic Spectrum
Long Wave, Medium Wave, FM

• Radio Waves
• Microwaves
• Infra red
• Visible Light
• Ultra Violet
• X-Rays
• Gamma rays

Cooking and Communication
Remote Controls and Grills/Heaters
Very narrow range, ROYGBIV, lasers
Sunburn, Skin Cancer, Sun Beds, Vit. D
Penetrates body, cause cancer, Look at broken
bones
Nuclear emission, cause cancer, treat cancer
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Analogue Digital Signals
Interference can be easily spotted and filtered
out of a digital signal. Multiplexing allows many
digital signals to be transmitted simultaneously..
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What can happen to a wave?
Satellite, Ionosphere, Fibre Optic Cable, Echo,
Ghosting off buildings, Mirrors Law of Reflection
Angle of Incidence Angle of Reflection

• Reflection
• Refraction
• Diffraction
• Interference

Bending of a wave as it enters a medium of
different density. Lenses and light, Mirages,
Seismic waves in Earth
Spreading out of a wave as it goes around an
object or through a gap. NB The gap has to be
almost the same size as the wavelength.
When two or more identical waves meet and cancel
each other out
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Seismic Waves

• P waves are LONGITUDINAL and can travel through
  all the Earths layers.
• S waves are TRANSVERSE and cannot travel through
  liquid layers such as the outer core
• Shadows of P and S waves help us to understand
  the structure of the Earth
• P waves travel fastest, arrive first
• S waves travel slower, arrive next
• L waves slowest, arrive last

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Global Warming and the Hole in the Ozone layer

• Global Warming is caused by a build up of CO2
  gases in the atmosphere that do not let
  reradiated longer wavelength IR waves to escape
  the atmosphere.
• Need to reduce COx gases released by industry

• The hole in the Ozone (O3) layer allows harmful
  UV rays from the sun through the atmosphere.
• Caused by CFCs
• UV causes skin cancer (melanoma)
• SPF suncream?