Topic 2

Aseptic Technique

What is it?

Aseptic technique is a technique in which the risks of contamination are lower as here are high safety regulations and step by step procedures in order to kill all dangerous bacteria

Why do we use it?

It's to assure that no other micro-organism than the one used in the experiment contaminates it or the results will be invalid

Why do we work close to the flame?

This is because of the updraft caused by the flame's heat, this will stop any bacteria settling on the equipment that could contaminate the experiment

Why do we shake our sample?

This is because it's the best way on ensuring the bacteria are properly mixed (as it could be a solution). Also helps with a lower bacteria contamination risk

Why do we not tape up the whole circumference of the agar plate?

This is because the bacteria inside need to breathe during incubation

Why do we put the plates in the incubators at 25 degrees Celsius and not higher?

It's the best average temperature for the bacteria to grow in and pathogens grow beyond 25 degrees Celsius

Cancer

Cancer is uncontrollable cell growth within an organism, it happen somewhere in the cell cycle where the cell division stage/check point is defied and therefore the cells begin to mutate and divide uncontrollably

Tumours

The Cell Cycle

Malignant Tumours

Secondary Tumours

Benign Tumours

What is a tumour?

A tumour is a collection/group of mutated cells however some AREN'T cancerous

This is NOT Cancer

This IS Cancer

These are formed when some malignant tumour cells break away and spread, which form tumours elsewhere

They usually grow quite slowly and don't spread to other parts of the body and have a covering made of normal cells

These tumours grow faster than benign tumours and can spread to other parts of the body and damage tissues which surround it. They could spread via the bloodstream (or the lymph) to form tumours secondary tumours

Spreading to other parts of the body is called metastatis

Cells need to divide to allow things such as the growth of an organism, repair of tissue or for asexual reproduction

In the cell cycle, cells divide to get bigger and do their jobs/carry out their functions

Cancer cells secrete their own growth hormones to get the nutrients they need

Immune system doesn't recognise them as they're your own cells so it doesn't destroy them