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Your body needs some things to keep constant:

  • Ion
  • Water
  • Sugar
  • Temperature

Ions are taken in by food and absorbed into the blood , some ions are lost in sweat, and urine

Wate is lost in various ways such as: 

  • From skin=sweat
  • From Lungs=Breath
  • From kidneys=Urine
  • All enzymes hould be at 37*c
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Plants can be cloned by cuttings= take cutting of the plant and plant them so they will gentically identical this a really cheap and quick way of cloning and it also can be cloned by

Tissue Culture= This is where a few plant cells are put in a growth mediumwith hormones and they grow into new plant clones. it is a very quick way ina small space

Adult cell cloning=

  • Egg cell, remove nucleus
  • Adult cell nucleus is remove and put into egg cell
  • Electric shock and split into two and implanted into woman
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Genetic Engineering

The main idea of this is to take a piece of DNA and put in someone elses cell

1)Human cell contains a gene for making insulin

2) Extract the DNA from some human cell

3)Use an enzyme( scissors) to cut the insulin gene out of the DNA

4)Bacteria cells contain na ring of plasmid

5) Use the same enzyme to stick the human insulin gene into the bacteria plasmid 

6) The lasmid holding the insulin is put into bacterua and mutates

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Evolution is the main

Different theories for evolution


Darwin’s theory

He came up with the idea of natural selection e.g. survival of the fittest(Individuals that have characteristics that make them more adapted to the environment which make them have a higher chance of survival are more likely to breed successfully)

Evolution can occur due to mutations

A mutation is a change in an organisms DNA. Most of the time it has no effect but sometimes in has a positive affect by producing a characteristic which gives the organism a better chance of surviving and reproducing. Over time the beneficial mutation will accumulate in a population.


Disagreements on Darwin’s theory-

·         Religious beliefs It was the first explanation for our existence without a need of god

·         She couldn’t give a good a good explanation for this

·         There was no evidence to convince many evidence


Lamarck’s Theory


Argued that if a characteristic was used a lot by an organism than it would come more developed over time. He also believed that acquired characteristics would be passed to the next generation.


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Plant Hormones

Auxin is a plant growth

It grown on the tip shoot and roots of a plant

Responds to light(phototropism)

                     Gravity( Gravitropism)

                    and moisture

if the tip is removed the plant will stop working

Extra auxin promotes growth in the shoot but inhibits growth in the root

  • Shoots grow towards light=
  • When a shoot is exposed to light is reaches towards it and grows faster so it bends towards the light
  • Shoots gro away from light= When a shoot is growing sideways , gravity produces an unequal distribution of auxin in the tip, with more auxin on the lower tip
  • Rootd grow towards gravity= A root grows towards gravity A root growing sideways will have more auxin on its lower side
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