B7: Further Biology

Peak Performance
1. Movement and Exercise
  1. Skeletal System
    1. your skeleton (figure 1) has a variety of uses...
      1. SUPPORT
        without a skeleton you would be a jellytastic flop, and not be able to stand up
      2. figure 1: your skeleton
      3. 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
      4. PROTECTION
        your skeleton protects your vital organs
    2. you are a vertebrate: your skeleton is on the inside
      1. Gary (right) is an invertebrate: his skeleton is on the outside
        "meow" -Gary
  2. Exercise
    1. Fitness
      1. FITNESS: how well you can do physical activities
    2. Injuries
2. Circulation
  1. Blood
    1. Components thereof
      1. 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
      2. plasma
        liquid that carries stuff...
        nutrients, eg glucose and amino acids
        waste, eg carbon dioxide and urea
        antibodies
        hormones
      3. white blood cells
        help to fight infection by protecting your body against attack from microorganisms
      4. platelets
        small cell fragments that help the blood to clot at the site of a wound
  2. The Circulatory System
    1. humans have a DOUBLE CIRCULATORY SYSTEM
3. Energy Balance
  1. Contrololololing Body Temperature
    1. your body should be kept at a constant temperature of about 37° - the optimum temperature for lots of reactions
  2. Controlling Blood Sugar
    1. Diabetes
      1. 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
      2. diabetes is where blood sugar level can't be controlled properly
    2. your body controls the level of sugar in your blood with a chemical called insulin
      1. 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
1. Human Impacts on Natural Ecosystems
  1. human activities can damage ecosystems by mucking up their inputs and outputs, ekzemple...
    1. farmers use fertilisers containing extra nutrients (like nitrates) to help plants grow
      1. this unbalances the ecosystem, because the input of nitrates is higher que normal, leading to EUTROPHICATION...
    2. humans take biomass out of ecosystems for our own use - this can damage an ecosystem...
    3. humans often clear natural areas of vegetation in order to grow crops and/or raise livestock
    4. human activities create non-recyclable waste that can't be used again within an ecosystem
  2. human systems AREN'T CLOSED LOOP SYSTEMS
2. Managing Ecosystems
3. Closed Loop Systems
  1. 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
    1. 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...
      1. 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
1. Genetic Testing
  1. genetic testing is used to identify genetic disorders
  2. the steps to test for a faulty gene are as follows:
    1. 1: take a DNA sample
      1. 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. 2: make a gene probe
      1. 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. 3: use the gene probe
      1. 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
2. Genetic Modification
  1. genetic modification = where a gene from one organism is transferred to another and continues to work
3. The Industrial Use of Microorganisms
  1. there are a variety of features of biochemistry that make them ideal for industrial use...
    1. rapid reproduction
      1. large quantities of the product can be made quickly
    2. presence of plasmids - small, circular molecules of DNA, separate from a microorganism's main DNA
      1. these can be easily genetically modified so that the microorganism is made to produce the desired product
    3. their simple, understood biochemistry
      1. this makes them easy to genetically manipulate without causing major problems
      2. we also can use our knowledge of them to control their growth conditions to produce an optimum yield
    4. ability to make complex molecules
      1. bacteria can make complex antibiotics, food additives and hormones that can't be easily synthesised in the lab
    5. lack of ethical concern
      1. one could grow loads of them and throw them away and no one would care
  2. first off, microorganism: bacterium, fungus or virus
  3. microorganisms are grown on a large scale to make lotsa products...
    1. ANTIBIOTICS
      1. 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
    2. FUNGI FOOD
      1. a type of single-celled protein made by fungi is used to make fake meat in veggie meals, eg Quorn
    3. ENZYMES FOR MAKING FOOD
      1. 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
    4. ENZYMES FOR WASHING POWDER
      1. 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
    5. BIOFUELS
      1. 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
    6. huge amounts of microorganisms are grown in containers qui s'appelle fermenters
      1. the conditions inside fermenters are adjusted to obtain OPTIMUM GROWTH YIELD
4. Nanotechnology
  1. nanotechnology is a branch of technology that uses tiny structures, about the size of some molecules, with a variety of applications....
    1. Annatechnology is a similar technology involving tiny people
    2. food can be made to last longer
      1. 例えば adding clay nanoparticles can kill harmful microorganisms
      2. some nanoparticles can kill harmful microorganisms to death
    3. some 'smart packaging' uses nanoparticles to change the packaging's properties depending on the conditions
      1. por ejemplo, a milk carton could be made to change colour when the milk goes off
5. Stem Cells
  1. tissues and organs grown from stem cells can be used to treat illnesses, например...
    1. leukaemia, a cancer of the blood or bone marrow, has been successfully treated using stem cell technology
      1. 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
    2. à l'avenir, stem cells could be used to treat spinal chord injuries by replacing damaged nerve tissue
6. Biomedical Engineering
  1. biomedical engineering uses engineering technologies to improve human health
    1. για παράδειγμα, faulty body parts can be replaced with nice shiny working ones...
      1. 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
      2. faulty heart valves can also be replaced with either animal or mechanical valves

Nächster

B7: Further Biology

Beschreibung

Zusammenfassung der Ressource

Medienanhänge

ähnlicher Inhalt

	Erstellt von Matthew Law vor mehr als 10 Jahre