Produces Evidenc for African Eve Theory:a) its inheritance
down the female line b) its high mutation rate
More usuful than nuclear DNA for tracking human migration/evolution: a) mitochondrial DNA is less
likely to have degraded over time b) mitochondrial DNA is more abundant
Climate Change
Impacted: a) mitochondrial DNA is less likely to have degraded
over time b) mitochondrial DNA is more abundant
Human Evolution
Evidence
Stone Tools
a) the development of stone tools over time b)
how these can be dated from their environment
Fossils
a) Ardi from 4.4 million years ago b) Lucy from
3.2 million years ago c) Leakey’s discovery of
fossils from 1.6 million years ago
Communication
Animal Communication
Sound
a) birds sing to show territory b) cats hiss to frighten c) deer
stags roar to challenge and attract
Chemical
pheromones - attract opposite sex
Visual
gestures - hand waving
body language - position of body to expres emotion
Plant Communication
Using Chemicals
Flowers produce scents to attract animals
The animal feeds on nectar and takes the
pollen to the next flower it feeds on
Mutualistic Relationship
Plants can also produce
chemicals for other plants
Roots - Chemicals from roots go
to the roots of other plants
Reduces competition for
water and mineral ions
Warning - Some release chemicals when
being attacked to warn other plants
Other plans produce
poison only when
warned because it
takes a lot of energy
Co-Evolution
A change in characteristic caused in one
species by a change in another species
Plants co-evolved their shape with animal pollinators so only
some species can feed at the flower
Benefit: Pollen will be transported to a similar flower
Animals don't have to compete with others to get nectar
Behaviour
Learned Behaviours
imprinting
Innate
Simple Behaviours
Habituation
The inhibitions of a response to a
repeated harmless stimulus
a) sniffer dogs
b) police horses
c) dolphins
classical conditioning
operant conditioning
Parenting
Parenting Behaviours
Birds & Mammals rear the young by:
a) protecting the young from danger b) helping the young to find food c) sheltering the
young from cold and wet d) teaching the young new skills, such as hunting
Evolutionary Strategy
Advantage of parental care in relation to evolution
a) increased chance of survival of offspring b) increased chance of
parental genes being passed on by the offspring
Courtship
Finding/selecting a suitable mate to
reproduce by/or advertising their qualities
Mating Strategies
a) a mate for life
b) several mates over a lifetime
c) a mate for a breeding season
d) several mates over one breeding season
Ethologists
Tinbergen - innate behaviour in gulls
Lorenz - impinting in geese
Fossey - social behaviour in gorillas
Goodall, social behaviour in chimpanzee
ROLE AND FUNCTIONS
NEW RIGHT
Rhythms
Photoperiodicity - A response of a plant that
changes as day length changes
Circadian Rhythm - A pattern of behaviour
that changes over a day period
Plant Defences
Use chemical defences to:
Deter pests that try to eat
them
Kill pathogens (bacteria fungi)
Human Food Supply
Pathogens and Pests cause damage to crop
Reduces Yield of Crop
Growing Microorganisms
Aseptic Technique -
Used to prevent infection of
wounds from surgry
Prevents food spoilage
Bacterial Growth
Bacteria will double
every 20 minutes in
the right conditions
Vaccines
Edward Jenner - Gave cowpox to a
boy that prevented small pox
Immunisation - Protects
you from infection
Vaccine - Contains pathogen/ Used to
immunise people
Antibodies
Monoclonal Antibodies - Antibodies that carry
useful chemical markers or treatmens
Pregnancy Test
Blood Clots/ Cancer Cells
Hybridoma Cell - From B
Lymphocyte & Cancer Cell. Makes
antibodies
FUNCTIONALISM
Kidneys
Waste products
Metabolic Reactions - Produce waste that diffuse into
the blood. They need to be removed
CO2 is waste product of respiration
Breakdown of excess amino acids in liver produces urea
Structure of Urinal System
a) renal artery and vein b)
kidneys c) ureters d) bladder
e) urethra
Role of Kidney
Remove urea from blood,. adjust ion &
water levels using osmoregulation &
selective reabsorption
Treatments for kidney failure
Kidney Dialysis
Organ donation
Nephron
Structure
a) glomerulus and Bowman’s capsule b) convoluted tubules c)
loop of Henlé d) collecting duct
Function
a) filtration in the glomerulus and Bowman’s capsule b) selective reabsorption of glucose c)
reabsorption of water (osmoregulation) d) removal of excess water in urine
Role of ADH
Produced by the Pituitary Gland
Regulates water content of the
blood - osmoregulation
The embryo needs to be in the thick uterus lining, so
that it can get its nutrients from the mother
Hormone Control
a) FSH stimulates maturation of follicles, which
stimulates oestrogen production b) oestrogen is
responsible for repair of the uterus wall
c) high levels of oestrogen stimulate a surge in LH, which
triggers ovulation d) corpus luteum secretes progesterone,
which maintains the lining of the uterus
e) progesterone inhibits FSH and LH production f) during
pregnancy, progesterone levels remain high
g) menstruation is triggered by a drop in oestrogen and
progesterone levels h) low progesterone levels allow an
increase in FSH levels
Negative Feedback Relativity
Changes of a released hormone stops the release of
other hormones e.g. progesterone inhibits FSH and LH
MARXIST
Fertilisation
Egg Cell
a) cytoplasm to provide nutrients b) haploid
nucleus containing one set of the genetic material
c) immediately after fertilisation the cell
membrane around the egg changes to block entry
of other sperm
Sperm Cell
a) acrosome containing enzymes b) haploid nucleus
containing one set of the genetic material c) middle
section containing mitochondria d) tail for motility
Infertility Treatments
Donation of Eggs
IVF
Surrogate Mother
Hormones
Sex Determination
Genotype - All of the genes of an indivisual
XX - Female
XY - Male
Phenotype - The look of the indivisual
Sex-Linked Inheritance
Allele - one half of a pair of genes
Dominant
Recessive
Haemophilia
Sex linked genetic disorder
XH - normal blood clotting
Xh - poor blood clotting (recessive)
EDUCATIONAL DIFFERENCES
Bio-Food
Microogranisms for Food
Advantages
a) rapid population growth b) ease of manipulation c) production independent of
climate d) use of waste products from other industrial processes
Making Yogurt
Type of Bacteria used, type of milk used,
temperature and the pH: Can change: the speed o
production and type of yogurt
a) Milk is warmed to 40'C b) a culture of bacteria is
added to the milk c) bacteria convert lactose in milk
to lactic acid d) lactic acid makes mixture taste sour
and thicken
Mycoprotein (Fake Meat)
A protein rich food made using a fungus -
Fusuarium sp. in large fermenters
Advantages - No saturated fat (red meat does) which can cause heart
disease. High fibre (red meat doesn't) - reduces glucose absorption and
insulin surges - reduces type 2 diabetes - reduces bowel cancer
Biotechnology
a) mitochondrial DNA is less likely to have degraded over
time b) mitochondrial DNA is more abundant
Fermenter - a vessel used to cultivate microorganisms for the
production of biomolecules on a large scale
Conditioning Fermenters
a) aseptic precautions b) nutrients c) optimum
temperature d) pH e) oxygenation f) agitation
World Problems
A GM Future?
Genetic Modification
by using bacterium: Agrobacterium tumefaciens as a vector e.g
gene for making flavinoid can be inserted into tomato cells to
make purple tomatoes
GM crop seeds cost a lot but purple tomatoes may help anyone with
cancer live longer.
MEDC: Money + No Lnad = GM
LEDC: No Money + Land = Biofules
Global Food Security
Increased Food Production
Conventional Plant-Breeding can develop new
varieties of plants that have higher yields
plants that have good yield and/or drought
tolerant, need less fertiliser are crossed
Plants grown from the seeds of the crosses are
selected for their good features and are crossed
with eachother
Selection and crossing is repeated until
high-yielding variety is produced
Pest Management
Pesticides
Pheremones
less attractive crop varieties
Bio-fuels
Advantges: a) biofuels are renewable (fossil fuels
aren't), crop growth takes CO2 from the air
Disadvantages: a) biofuel crops need land to grow on, and this may take land
needed for growing food crops
Insect-resistant plants
Use of Bt in plants
Advantages:
a) crop damage is reduced so crop yield should increase b) less
chemical insecticide is needed so harmless/useful insects are less
likely to be harmed (improves bio-diversity)
Disadvantages:
a) seed from transgenic plants is more expensive than seeds from non transgenic b) insect pests may become resistant to Bt c)
Pollination would cause Bt gene to transfer to other plants and make them resistant to plants to
Technology
Enzyme Technology
Chymosin
Enzyme that effects proteins in
milk. Making solid curds and liquid
whey. Curds are used for cheese
Natural chymosin comes from calves' stomachs
Enzyme can be made using
GMB for vegetarian cheese
Invertase
(Sucrase) - converts
sugar sucrose into
glucose and fructose.
Commercially produced by
yeast - used to make
sweets taste sweeter and
soft centres
Washing Powder
Protease enzymes digest proteins and
lipase digests fats and oils, usually found
as stains on clothes.
You can wash low temperatures with these enzymes, with
washing powder, which saves time and energy for heating
DNA Technology
Making Human Insulin
You need: a) restriction enzymes
b) ligase c) sticky ends