Name: 16.5 points Total

Quiz Two

1. A fungal mating type system that has one locus is said to be Unifactorial (bipolar).. (0.5 pts)

2. Define: (1 pt each)

Hermaphrodite:

An organism (fungus) with both male and female reproductive parts on the same thallus.

In lecture “ a single thallus with both male and female structures”

Heterothallic:

Self-sterile- an organism that requires a compatible partner for mating. Compatibility is defined by mating type loci.

3. Defend the statement: Some, but not all hermaphrodites can mate with themselves. (2 pts)

Homothallic hermaphrodites can mate with themselves, but heterothallic hermaphrodites can not.

4. In the tetrapolar mating cross, A1B2 x A3B5, list all of the possible mating types of the progeny (2 pts)

A1B2, A1B5, A3B2, A3B5

5. In fungi, sexes are defined by (0.5 pts/correct answer. Select all correct answers)

a. whom you are able to mate with

b. which structure is the donor or recipient of the fertilizing nucleus

c. having a unifactorial or bifactorial mating system

d. all of the above

6. The mating type locus in fungi

a. defines a single gene that is different in compatible mating partners

b. may contain multiple genes

c. contains non-homologous DNA in compatible partners

d. allows recognition of compatible partners and induction of plasmogamy

e. determines who is a male and who is a female

FILL IN THE BLANKS (0.5 pts each)

7. Use these terms to fill in the blanks: (zoospores, basidiospores, Pilobolus sporangia, hydrophobic spores

basidiospores are both forcibly discharged and passively dispersed.

zoospores require water for dispersal

Pilobolus sporangia rely only on forcible discharge for dispersal in order to be dispersed only a limited distance from where they form.

Hydrophobic spores are passively discharged and aerially dispersed, and may travel long distances.

8. Constitutive dormancy is determined by internal factors of the spore and requires a trigger to break dormancy. In contrast, exogenous dormancy is imposed by unfavorable environmental conditions and requires continuous favorable conditions for growth.

True/False: (0.5 pts)

1. T ______Most fungal sexual spores are primarily for survival during dormancy, not for dispersal.

2. ___F___ Spores are either subject to constitutive or exogenous dormancy, not both.

3. ___T__ Spores of leaf pathogens are generally larger than those of soil fungi to improve their chances of landing on their leaf targets.