Bacteria Flashcards
1
Q
Coccus
A
- spherical
2
Q
Bacillus
A
- rod-shaped
3
Q
Spirilla
A
- spiral shaped
4
Q
Vibrios
A
- comma-shaped
5
Q
Wall
A
- a rigid cell wall
- large molecules called peptidoglycans
- mixture of proteins, lipids and carbohydrates
- keeps bacteria’s shape
6
Q
Membrane
A
- plasma membrane
- acts as a mitochondrion, endoplasmic reticulum, and sometimes a chloroplast
- ## controls exit and entry of materials
7
Q
Nucleoid
A
- no nuclear membrane
- DNA is not combined with histone (a protein) as in Eukaryotes
- single chromosome of a closed loop of DNA
- controls function or bacterium and division
8
Q
Flagellum
A
- enable movement ( as opposed to squeezing their body to crawl or wind like a corkscrew)
- tail like structure
9
Q
Cytoplasm
A
- contains granules and ribosomes for protein synthesis
10
Q
Plasmid
A
- small circular double stranded DNA
- contains genes for antibiotic resistance
11
Q
Prokaryote and Eukaryote
A
- no membrane bound nucleus
- nucleus
12
Q
Harsh environments
A
- bacteria can become dormant and form spores
- can form an endospore (rounds of the protoplasm with a thick wall) allowing them to stay dormant for years
- only killed in temperatures of 120 degrees celsius
- heat resistant enzymes
- pump proteins to extrude salts and chemicals
- ability to utilize different carbon sources
13
Q
Redproduction
A
- asexual
- DNA replicates
- nucleoid divides into two so each cell has a complete set of DNA
- Membrane forms across the middle of he cell (separating the cytoplasm into two identical portions)
- a new wall forms on the membrane
- binary fission happens (splits into two)
- each cells lives normally growing back to its maximum size
14
Q
Environment and industry
A
- degrade herbicides
- eat or neutralise toxic waste (bioremediation)
- synthesise riboflavin (a vitamin B)
- seperate fibres (jute, hemp and flax for ropes and sacks)
- replace pesticides (Bacillus thuringiensis)
- decompose sewage and waste to harmless sludge
- produce food (by fermentation)
- make probiotics (beneficial bacteria to help digest food)
- cycling of nutrients
- decomposition
- nitrogen fixing bacteria (convert gaseous nitrogen into ammonia)
- nitrifying bacteria (convert ammonia into nitrates and nitrites)
- denitrifying bacteria ( converts nitrates into nitrogen)
15
Q
Genetic engineering
A
- Bacteria can be genetically modified to insulin
- Location of the section containing the DNA
- specific enzyme is used to extract the required gene from the human chromosome
- plasmids are removed from bacteria cell
- DNA of the plasmid is cu open with an enzyme
- human gene is inserted into the plasmid
- plasmid acts as a vector
- bacterial cells take up the genetically modified plasmid
- transformed cell produce tiny masses of insulin
