B6 Flashcards
Describe bacteria cells?
- May have Flagellum (whip like tail) for movement
- have a cell wall to maintain shape and stop bacterium from absorbing water and bursting
- have bacterial DNA for cell replication and to control cells activities
What are BACTERIA?
- ,microscopic single called organisms .
No true nucleus, mitochondria, chloroplasts or a vacuole
How do bacteria reproduce?
- BINARY FISSION - by splitting in two
- reproduce rapidly in the right conditions.
Bacteria grow and reproduce very fast, what does this mean?
- diseases spread quickly as conditions inside the human body are ideal for bacterial growth ( warm, moist, food supply)
- food can become contaminated by bacteria and toxic waste produced by bacteria as they feed
How do viruses invade a living cell?
1- the virus attaches to a host cell and injects it’s genetic material into the cell
2- it used the cell to make components for a new virus
3- the host cell splits open to release the virus
What is yeast?
- a single called fungus
- reproduces asexually by budding
What do yeast cells need to reproduce quickly?
- lots of sugar
- optimum heat (40) and PH
- the removal of waste products, such as alcohol, which poison it
What are ASEPTIC TECHNIQUES?
The process of growing and transferring bacteria without contaminating the sample by touching or breathing on it and without any loss of microbes to the surroundings
How can pathogens enter your body?
- airborne microorganisms enter through nose
- ,contaminated food, through mouth
- injected: insect bites, needles or wounds
- reproductive organs during sex
What illness does bacteria cause and how is it transmitted?
- cholera
- and food poisoning
- throughout water
- through food
What illness do viruses cause and how is it transmitted?
- influenza through airborne droplets
- chickenpox through contact or airborne
What illness does fungi cause and how is it transmitted?
- athletes foot through direct contact
What is CARBOLIC ACID?
- an antiseptic which kills bacteria
How is yogurt made?
1- the equipment is sterilised to kill pathogens
2- raw milk is heated to 80 to kill bacteria and then quickly cooled
3- live bacterial culture is added to the milk
4- the bacteria reproduce and feed on the lactose sugar producing lactic acid, which gives a sharp taste to the yoghurt and thickens and preserves it
5- it is sampled
6- flavours and colours added
What is fermentation?
- anaerobic respiration in yeast.
- produces alcohol
- sugars are broken down by yeast in the absence of oxygen to produce alcohol.
- different fruits and seeds are used to provide sugar and flavour
- carbon dioxide is also produced