without a skeleton you
would be a jellytastic flop,
and not be able to stand up
figure 1: your skeleton
MOVEMENT
joints allow bones to move
and are composed of various bits...
a smooth layer of
cartilage and synovial
fluid between the bones
reduces friction
between the bones
elastic ligaments
stabilise joints while
allowing movement
tendons
connect bones and muscles,
transmits forces between the two
when the muscle contracts,
a tendon pulls on the bone
you need a skeleton to achieve
any amount of elegant feline poise
muscles pull on bones to move them
muscles move the bones
(and consequently the limb)
at a joint by contracting
PROTECTION
your skeleton protects
your vital organs
you are a vertebrate: your
skeleton is on the inside
Gary (right) is an invertebrate:
his skeleton is on the outside
"meow" -Gary
Exercise
Fitness
FITNESS: how
well you can do
physical activities
Injuries
Circulation
Blood
Components thereof
red blood cells
transport oxygen from the
lungs to the rest of the body
have no nucleus,
so can carry lotsa
haemoglobin
have a biconcave shape to
give them a large surface
area for exchanging oxygen
plasma
liquid that carries stuff...
nutrients, eg
glucose and
amino acids
waste, eg carbon
dioxide and urea
antibodies
hormones
white blood cells
help to fight infection
by protecting your
body against attack
from microorganisms
platelets
small cell fragments that help the
blood to clot at the site of a wound
The Circulatory System
humans have a DOUBLE
CIRCULATORY SYSTEM
Energy
Balance
Contrololololing Body Temperature
your body should be kept at a constant
temperature of about 37° - the optimum
temperature for lots of reactions
Controlling Blood Sugar
Diabetes
there are two types...
type 1
type 1 is where the pancreas
stops producing insulin
this means that the blood sugar level
of a person suffering from type 1
diabetes can rise to a dangerous level
it's controlled by injecting
insulin into the blood,
usually at mealtimes
the injection needs to have
the right amount of insulin to
ensure that the body doesn't
remove too much sugar
type 2
type 2 diabetes often
develops later in life
the risk of developing it is
increased by having a poor
diet or by being obese
it occurs when the body
no longer responds to its
own insulin, or it doesn't
make enough
this can again cause a
person's blood sugar level
to rise to a dangerous level
it can be controlled by
exercising and eating a carefully
controlled diet
მაგალითად, someone who suffers from type 2 diabetes
can keep their blood sugar levels steady by eating foods
that are high in fibre and complex carbohydrates - these
foods are digested more slowly than simple sugars, so
the sugar is absorbed into the blood over a longer period
of type, and the blood sugar level rises more slowly
diabetes is where blood sugar
level can't be controlled properly
your body controls the level
of sugar in your blood with a
chemical called insulin
when your blood sugar level
get too high, məsələn when
you eat a delicious gluten free
cake, your pancreas releases
insulin, which removes the
excess sugar from the blood
Ecosystems
Human Impacts on
Natural Ecosystems
human activities can damage ecosystems by
mucking up their inputs and outputs, ekzemple...
farmers use fertilisers containing extra nutrients (like nitrates) to help plants grow
this unbalances the ecosystem, because
the input of nitrates is higher que normal,
leading to EUTROPHICATION...
humans take biomass out of ecosystems for our own use - this can damage an ecosystem...
humans often clear natural areas of vegetation in order to grow crops and/or raise livestock
human activities create non-recyclable waste that can't be used again within an ecosystem
human systems AREN'T
CLOSED LOOP SYSTEMS
Managing
Ecosystems
Closed Loop Systems
a perfect closed loop
system is a system that
has no waste because
the output from one part
of the system becomes
the input to another part
I couldn't find any images up to
my standard on the interweb, so
I copied the ones in the revision
guide to make my own...
there's more room for me to explain down here...
this is what a PERFECT
CLOSED LOOP SYSTEM
looks like: everything is
recycled within the system
I hate to disappoint you, but no
ecosystem is perfect like this -
some outputs are always lost
உதாரணமாக...
some dead organic matter and nutrients can
be carried out of an ecosystem by air or
water, er enghraifft fallen leaves may be blown
away be the wind or carried away by rivers
some
organisms
migrate from
one ecosystem
to another, eg
the Mongols
even if it's not *perfect*, an
ecosystem can nevertheless still
be a closed loop system, like so:
New Technologies
Genetic Testing
genetic testing is used to
identify genetic disorders
the steps to test for a
faulty gene are as follows:
1: take a DNA sample
DNA isolated from white blood cells is often used to
test for genetic disorders ∵ it's quick and easy to take
a blood sample containing loads of white blood cells
2: make a gene probe
to identify a faulty gene, a gene probe is produced - a strand of
bases that's complementary to the faulty gene you're looking for
3: use the gene probe
the gene probe is mixed with
the DNA - si le gene est
present, the probe will stink to
it, their bases locking together
perfectly like in the diagram
to see the gene
probe, a fluorescent
chemical marker is
attached to the probe
- if the faulty gene is
present, it will glow
under UV light
Genetic Modification
genetic modification = where a gene from one organism
is transferred to another and continues to work
The Industrial Use
of Microorganisms
there are a variety of features
of biochemistry that make
them ideal for industrial use...
rapid reproduction
large quantities of
the product can
be made quickly
presence of plasmids - small,
circular molecules of DNA, separate
from a microorganism's main DNA
these can be easily
genetically modified so
that the microorganism
is made to produce
the desired product
their simple, understood biochemistry
this makes
them easy to
genetically
manipulate
without causing
major problems
we also can use our
knowledge of them to
control their growth
conditions to produce
an optimum yield
ability to make complex molecules
bacteria can make
complex antibiotics, food
additives and hormones
that can't be easily
synthesised in the lab
lack of ethical concern
one could grow
loads of them and
throw them away and
no one would care
first off, microorganism:
bacterium, fungus or virus
microorganisms are
grown on a large
scale to make lotsa
products...
ANTIBIOTICS
some types of bacteria
and fungi can be used
to produce medicines
eg penicillin is an antibiotic
made by growing Penicillium
mould in a fermenter
FUNGI FOOD
a type of single-celled protein
made by fungi is used to make fake
meat in veggie meals, eg Quorn
ENZYMES FOR MAKING FOOD
traditionally cheese is made using
a mixture of enzymes called rennet
from the lining of a calf's stomach
nowadays, chymosin, the important
enzyme in rennet, is produced by
genetically modified organisms in large
quantities as a veggie substitute for rennet
ENZYMES FOR WASHING POWDER
enzymes produced by bacteria
can be used to make biological
washing powders - the enzymes
help to break down stains
exempli gratia amylase enzymes
can remove carbohydrate stains
like jam and chocolate, and
lipase gets rid of fat stains, like
butter, oil and your mum
BIOFUELS
microorganisms
can be used to
make fuels, for
example...
yeast can be used to produce ethanol, a
waste product of anaerobic respiration
in some countries, na przykład Brazil,
cars are adapted to run on a mixture of
ethanol and petrol known as 'gasohol'
microorganisms can be used to produce biogas,
a fuel used for heating, cooking, lighting, etc
it's made by the
fermentation of
plant and animal
waste containing
carbohydrates
huge amounts of microorganisms
are grown in containers qui
s'appelle fermenters
the conditions inside fermenters
are adjusted to obtain
OPTIMUM GROWTH YIELD
Nanotechnology
nanotechnology is a branch of
technology that uses tiny structures,
about the size of some molecules,
with a variety of applications....
Annatechnology is a
similar technology
involving tiny people
food can be made to last longer
例えば adding clay
nanoparticles can kill
harmful microorganisms
some
nanoparticles
can kill harmful
microorganisms
to death
some 'smart packaging' uses
nanoparticles to change the packaging's
properties depending on the conditions
por ejemplo, a milk carton
could be made to change
colour when the milk goes off
Stem Cells
tissues and organs grown
from stem cells can be used
to treat illnesses, например...
leukaemia, a cancer of the blood or
bone marrow, has been successfully
treated using stem cell technology
bone marrow transplants containing stem cells can
replace the leukemia sufferer's faulty bone marrow, the
stem cells in it being able to produce healthy blood cells
à l'avenir, stem cells could be used to treat spinal chord injuries by replacing damaged nerve tissue
Biomedical
Engineering
biomedical engineering uses
engineering technologies to
improve human health
για παράδειγμα, faulty body parts can be
replaced with nice shiny working ones...
if the group of cells controlling the tempo of
one's heartbeat stops working, the heartbeat
may become dangerously irregular
the faulty cells can be replaced by an
artificial pacemaker, which uses an
electric current to control the heartbeat
faulty heart valves can also be replaced
with either animal or mechanical valves