yr 10 revision cloning

PowerPoint Presentation: 

Clones Plants can reproduce ASEXUALLY. The offspring are genetically ________ to the parent plant and are called _________. Two examples: 1) This spider plant has grown a rooting side branch (“stolon”) which will eventually become __________. 2) A gardener has taken cuttings of this plant (which probably has good characteristics) and is growing them in a ____ atmosphere until the ____ develop. Words – clones, damp, independent, roots, identical

Tissue culture: 

Tissue culture In plant tissue culture, small group of cells from a plant grow on jelly containing all the nutrients a plant requires. The cells divide and grow into new plants, with all the same genes: they are CLONES.

Embryo transplants: 

Embryo transplants In animal transplants A fertilised egg(a zygote) is taken It divides to form a ball of cells all genetically identical. The cells are separated B4 they become speciallised. Each cell divides to become a new ball of cells (an embryo) Each identical embryo is transplanted into a host mother and develops into a new individual

Adult cell cloning and replacing damaged skin.: 

Adult cell cloning and replacing damaged skin. Adult cell cloning, the nucleus of a egg cell is removed and replaced with the nucleus of an adult body cell . The egg cell develops into an individual which is a clone of the body cell donor . Skin drafts. A few healthy skin cells from the victim are cultured in a growth medium, to produce large sheets of skin which then can be transferred to burnt areas by plastic surgery.

Genetic engineering: 

Genetic engineering Genetic engineering is a technique of transferring a gene or chromosome of one organism to another, which is then genetically modified (GM). A gene for a desired characteristic from one organism is inserted into embryos of a plant. When they grow into a plant they show the desired characteristic. Soya beans becoming resistant to the herbicide which are sprayed to kill weeds which compete with them.

PowerPoint Presentation: 

Genetic engineering - Insulin Step 1: Using RESTRICTION ENZYMES “cut out” the part of the human chromosome that is responsible for producing insulin . Step 2: Using another restriction enzyme cut open a ring of bacterial DNA (a “plasmid”). Other enzymes are then used to insert the piece of human DNA into the plasmid. Step 3: Place the plasmid into a bacterium which will start to divide rapidly. As it divides it will replicate the plasmid and make millions of them, each with the instruction to produce insulin. Commercial quantities of insulin can then be produced.

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Evolution Evolution is the slow, continual change of organisms over a very long time. All living things on the Earth have developed from the first simple life forms that arrived 3,000,000,000 years ago. One of the effects of evolution is that species will become better adapted to their environment. If these species don’t adapt they may become extinct due to being unable to deal with any of these factors… Increased competition Changes in the environment New diseases New predators

PowerPoint Presentation: 

Evolution My key observations: All living things produce more offspring than survive to adulthood In spite of this, population sizes remain roughly constant Variation exists among species Characteristics can be passed on from one generation to the next. These observations led me to the conclusion that species evolve over a along period of time by a mechanism called “Natural Selection”. The main evidence for this is from fossil records.

Natural selection in action: 

Natural selection in action Peppered moths are usually pale with dark speckles. They are camouflaged from predator and birds. In cities, the industrial revolution blacken buildings and trees with soot. Dark moths – a variation in the species survived better as camouflaged. Dark moths were being favoured by Natural Selection. Pale moths were eaten by birds. Now with cleaner air, most peppered moths are pale again.

Fossils and evolution: 

Fossils and evolution A fossil forms when a dead organism is buried in sediment, more sediment piles on top, the pressure (and temperature) increases and the organism turns to stone. Comparing fossil remains with present day plants and animals show us evolution. Fossil evidence and the Theory of evolution support the idea that all present day species evolved from first life forms.

Deforestation: 

Deforestation Permanent clearing of forests, particularly tropical rainforests. Trees are cut for timber or burnt to make way for farms. Deforestation reduces rate of CO2 is removed from the air in photosynthesis. Burning wood releases more CO2 into the atmosphere. Deforestation destroys habitats and reduces biodiversity: species become extinct+ survivors will show reduced variation.

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The Carbon Cycle CO 2 in air 1. CO 2 is taken in by plants for photosynthesis and turned into carbohydrates 2. Plants release CO 2 through respiration 3. The carbon taken in by plants is then eaten by animals 5. Animals (and plants) die and their remains are fed on by microbes 6. These microbes also release CO 2 through respiration 4. Animals release CO 2 through respiration

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The Greenhouse Effect We get heat from the sun: A lot of this heat is _______ back into space. However, most of it is kept inside the Earth by a layer of gases that prevent the heat escaping by _______ and then re-radiating it back again. This is called the _________ Effect. It has always been around, but is currently being made worse due to: Burning (releasing CO 2 ) __________ (removing trees that remove CO 2 ) Increased micro organism activity (from rotting ______) Cattle and rice fields (they both produce _______) These changes will cause GLOBAL WARMING and RISING SEA LEVELS Words – methane, radiated, absorbing, deforestation, waste, greenhouse

PowerPoint Presentation: 

Sustainable Development Sustainable development is all about preserving the world for tomorrow. There are three main strands: Economic development Social development Environmental protection Examples of sustainable development include: Replanting trees after chopping them down Limiting the number of fish allowed in a catch Protecting endangered species Recycling rubbish to save resources. Insulating buildings to reduce heat energy lost. Walking or cycling to reduce the use of cars that burn fuel Using public transport.