Bacteria, Viruses, Fungi + Yeast Flashcards
To which kingdoms do amoeba and bacteria belong?
amoeba - protista
bacteria - monera
which kingdom contains eukaryotic organisms between monera and Protista.
protista
Comment on the relationship between the mode of nutrition and the environmental roles of a saprophyte
saprophytes consume dead matter and are therefore reponsible for decomposition and nutrient recycling in the environment.
In the sexual reproduction of rhizopus, what is the significance of opposite strains of hyphae growing close together ?
The swellings form and grow towards each other and eventually touch.
In the sexual reproduction of rhizopus, describe the production progametangia.
This is the swellings at the tip of the hyphae.
In the sexual reproduction of rhizopus, what is the role of meiosis?
The zygospore germinates by meiosis.
State any 2 harmful effects of fungi?
Human disease such as athletes foot and ringworm.
Poisonous mushrooms
What are the circumstances under which sexual reproduction of the rhizopus occurs?
Lack of water
unsuitable temperature
unsuitable pH
Lack of nutrients
Is oxygen necessary during fermentation ?
No
Where in the cells does fermentation occur ?
cytosol
When preparing alcohol using yeast, from which substance did the yeast make the alcohol?
Glucose
When preparing alcohol using yeast, what is the optimum temperature and how was it maintained?
20C - 35C
using a water bath
When preparing alcohol using yeast, How did you know when the fermentation was finished ?
No more carbon dioxide was produced
When preparing alcohol using yeast, how did you test for the presence of alcohol and what is the colour of the positive result ?
Using the iodoform test
yellow
State the 2 sources of energy that bacteria can use make their food
Sunlight or energy from chemical reactions.
What is the difference between facultative anaerobes and obligate anaerobes ?
facultative respire in the presence or absence of oxygen while obligate respire only in the absence of oxygen.
In the growth curve of a bacteria, explain why some of them survive ?
They form endospores
During continuous flow batch processing, explain why its desirable to keep bacteria in the log phase of growth
To maximise yield
During continuous flow batch processing, at what stage of growth curve is the product removed ?
After stationary phase
To what kingdom do yeasts belong ?
Name another member of this kingdom
fungi
mushrooms/ rhizopus/ penicillium
Apart from a source of nutrition, give one other function of the agar.
Its a medium for growth
In relation to the growth of leaf yeasts in the lab, how can you be certain that the leaf is the only possible source of the yeast ?
You can use a sterilised piece of leaf as a control
In relation to the growth of leaf yeasts in the lab, what is the step taken to prevent the contamination of the lab by the yeast ?
seal the plates
In relation to the investigation of anaerobic respiration in yeast, name 2 steps taken to ensure anaerobic conditions.
Boil water then cool it to remove all oxygen.
Add layer of oil to prevent oxygen from entering.