LIFE CYCLE
A difference between asexual and sexual reproduction in fungi.
Asexual reproduction
-rapid, requires only one parent
-involves no fusion of cells or genetic recombination
-relies strictly on mitosis to produce clonal spores.
Sexual reproduction
-requires two compatible mating types (+ and -)
-features cellular and nuclear fusion
-includes a unique dikaryotic phase (n+n)
-undergoes meiosis to create genetically diverse spores.
Why is fungi non-motile?
Chitin physically stops the cell from changing shape or developing locomotory appendages.
What would happen to the protection of hyphae if septa is not present?
Lack of septa allows pathogens or toxins to spread throughout the entire organism.
What is the difference between asexual and sexual reproduction modes in Ascomycota?
- asexual is the primary method of multiplication, via mitotic spores called conidia produced on conidiospores
- sexual - fusion of compatible hyphae, forms ascocarps that house the asci
Compare the use of fungi in medicine and food production.
Produce important compounds such as antibiotics, for example penicillin, as well as yeast are used in fermentation. (While other fungi are involved in products such as bread and certain cheeses.)
The four stages of the general sexual reproduction process of fungi.
Plasmogamy, Karyogamy. Meiosis, Germination
Why are yeasts unicellular?
To have maximum efficiency in liquid & sugar-rich environment and evolutionary reduction for rapid reproduction.
Comparison of movement of nutrients between Septate and Aseptate.
Septate moves between cells through pores, Aseptate moves freely throughout hyphae.
Why might a fungus switch from sexual reproduction to asexual reproduction when the conditions are unfavourable?
Asexual reproduction allows fungus to reproduce quickly. When conditions are unfavourable, fungal carries out sexual reproduction to create genetic variation, which can increase the chances of the offspring to survive in the new conditions.
Why are fungi important even though they cannot produce their own food?
They obtain nutrients by decomposing organic matter or forming relationships with other organisms, and in doing so they contribute to nutrient cycling and ecosystem functioning.