communcable diseases Flashcards
Define communicable diseases
A disease caused by pathogens that can be transmitted from one organism to another- normally species specific, but can pass spread between species. Plants only spread to other plants
Define communicable diseases
A disease caused by pathogens that can be transmitted from one organism to another- normally species specific, but can pass spread between species. Plants only spread to other plants
How are communicable diseases passed along
through same species or from one to another. Vectors are often involved in spreading animal and plant diseases
Common vectors in communicable diseases
water
insects- mosquitos
The effects on of communicable diseases
13 million die each year
Different pathogens?
Bacteria
Protoctista
Virus
Fungi
Describe bacteria
Prokaryotes- no membrane bound organelles
How is bacteria classified?
By the shape or cell wall
What are the different shapes of bacteria?
Rod shaped (bacilli) Spherical (cocci) Comma (Vibrios) Spiralled (spiralla) Corkscrew (spirochaetes)
What are the two different bacteria cell walls?
Why is this useful
- Gram positive bacteria- looks purple/blue when stained under microscope
- Gram negative bacteria- Red when under microscope and also stained
-Cell wall affects how the bacteria will react to different antibiotics
Describe viruses
Non living infectious agents that are around 0.3um in diameter.
Structure- DNA surrounded by protein
Ultimate parasites (scientists say)
How do viruses infect?
Invade living cells, where its genetic material takes over their biochemistry to make more viruses. They multiply rapidly and evolve to adapt to the host
Describe how viruses take over bacteria? name of this pathogen?
BACTERIOPHAGES
They take over the bacteria cells and use them to reproduce and then destroy the bacteria at the same time.
Describe protoctista?
Single celled eukaryote or cells grouped in colonies. Some are parasitic and cause harm to plants and animals.
Describe how people come infected through protoctista
They use animals or people as their hosts. May need a vector too transfer them to another host (malaria, water pollution)
Describe fungi and how it infects
Can cause devastation in plants,
Eukaryotic cells which are multi cellular
It can’f photosynthesis so digest food extracellularly
Many feed on dead decaying matter. known as saprophytes
Some are parasitic feeding on plants and animals
Adapted to spread a huge distance through reproduction
How does fungi affect plants
affects the leaves of the plants which stops them from photosynthesising.
How are communicable diseases passed along
through same species or from one to another. Vectors are often involved in spreading animal and plant diseases
Common vectors in communicable diseases
water
insects- mosquitos
The effects on of communicable diseases
13 million die each year
Different pathogens?
Bacteria
Protoctista
Virus
Fungi
Describe bacteria
Prokaryotes- no membrane bound organelles
How is bacteria classified?
By the shape or cell wall
What are the different shapes of bacteria?
Rod shaped (bacilli) Spherical (cocci) Comma (Vibrios) Spiralled (spiralla) Corkscrew (spirochaetes)
What are the two different bacteria cell walls?
Why is this useful
- Gram positive bacteria- looks purple/blue when stained under microscope
- Gram negative bacteria- Red when under microscope and also stained
-Cell wall affects how the bacteria will react to different antibiotics
Describe viruses
Non living infectious agents that are around 0.3um in diameter.
Structure- DNA surrounded by protein
Ultimate parasites (scientists say)
How do viruses infect?
Invade living cells, where its genetic material takes over their biochemistry to make more viruses. They multiply rapidly and evolve to adapt to the host
Describe how viruses take over bacteria? name of this pathogen?
BACTERIOPHAGES
They take over the bacteria cells and use them to reproduce and then destroy the bacteria at the same time.
Describe protoctista?
Single celled eukaryote or cells grouped in colonies. Some are parasitic and cause harm to plants and animals.
Describe how people come infected through protoctista
They use animals or people as their hosts. May need a vector too transfer them to another host (malaria, water pollution)
Describe fungi and how it infects
Can cause devastation in plants,
Eukaryotic cells which are multi cellular
It can’f photosynthesis so digest food extracellularly
Many feed on dead decaying matter. known as saprophytes
Some are parasitic feeding on plants and animals
Adapted to spread a huge distance through reproduction
How does fungi affect plants
affects the leaves of the plants which stops them from photosynthesising.
What do viruses attack?
The cell metabolism
How do viruses attack the cell metabolism?
The viral genetic material invades the host cells and is inserted into the host of the DNA, using host cells to make more viruses and burst the cell- destroying cells and spreading to infect other cells
What do protoctista infect in the body?
Take over cells and break them open as new ones emerge. But don’t take over genetic material.
How do protoctista invade cells in body?
Simply digest and use the cells content as they reproduce.
What does Fungi attack?
Living cells.
How do fungi invade cells.
They digest the cells destroying them. This combined with the body’s response creates the symptoms of disease
What does bacteria produce during invasion of the cells
Toxins that poison host cells. They break down the cell membrane- damaging and inactivating enzymes. Cell division can no longer take place
What does some fungi produce?
Toxins which affect the host cell- cause disease
