Vaginal yeast infections are caused by the fungus Candida albicans, which is one of a community of microorganisms that are always present in the vagina in low concentrations. One of the factors that can bring about a yeast infection is the initiation of the use of certain antibiotics. Why would the use of antibiotics foster an unhealthy multiplication of C. albicans in the vagina?

Fungi (select all that apply):

a. are more closely related to plants than animals.

b. make their own food.

c. use existing organic material as their food.

d. digest their food externally.

e. are usually multicellular.

Most fungi are composed almost entirely of:

a. ball-shaped objects called hypha.

b. leaves and stems.

c. reproductive cells called spores.

d. slender filaments called hyphae.

e. slender filaments called septa.

Fungi cause (select all that apply):

a. tetanus.

b. athlete’s foot.

c. common colds.

d. dry rot.

e. wheat rust.

Fungi are important to humans as (select all that apply):

a. a source of citric acid.

b. photosynthesizing organisms.

c. the source of some antibiotics.

d. decomposers of dead organic material.

e. producers of oxygen.

Fungi reproduce through cells called spores that (select all that apply):

a. have a single set of chromosomes.

b. often are released from structures called fruiting bodies.

c. usually are released in huge numbers.

d. must fuse with another spore to bring about germination.

e. germinate without fusing with another cell.

Fungi that obtain their nutrition from living organisms are referred to as _______, while fungi that obtain their nutrition from dead organic material are referred to as________.

a. carnivores; herbivores

b. saprophytes; parasites

c. omnivores; herbivores

d. parasites; saprophytes

e. saprophytes; herbivores

The association between fungi and algae (or bacteria) in forming lichens is one of _______in that _______.

a. parasitism; only one party benefits from the relationship

b. competition; neither party benefits from the relationship

c. competition; both parties are vying for the same resources

d. mutualism; both parties are benefiting from the relationship

e. saprophytism; one party is feeding on the dead remains of the other

The mycorrhizae formed by the association between fungal _____ and plant _____ are found in ______ seed plants.

a. hyphae; roots; only a few

b. spores; leaves; only a few

c. hyphae; roots; the vast majority of

d. fruiting bodies; roots; the vast majority of

e. hyphae; stems; only a few

In contrast to bacteria and archaea, all protist cells have a _______, which makes protists eukaryotes. While some protists are large, most are _______; all of them live in environments that are at least moist if not fully _______.

The organisms known as phytoplankton are important to life in general for two reasons: They produce most of the world’s atmospheric _____ and they lie at the base of most aquatic _____.