An oak is a tree or shrub in the genus Quercus (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 600 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably "Lithocarpus" (stone oaks), as well as in those of unrelated species such as "Grevillea robusta" (silky oaks) and the Casuarinaceae (she-oaks). The genus "Quercus" is native to the Northern Hemisphere, and includes deciduous and evergreen species extending from cool temperate to tropical latitudes in the Americas, Asia, Europe, and North Africa. North America contains the largest number of oak species, with approximately 90 occurring in the United States, while Mexico has 160 species of which 109 are endemic. The second greatest center of oak diversity is China, which contains approximately 100 species. 

Oaks have spirally arranged leaves, with lobate margins in many species; some have serrated leaves or entire leaf with smooth margins. Also, the acorns contain tannic acid, as do the leaves, which helps to guard from fungi and insects. Many deciduous species are marcescent, not dropping dead leaves until spring. In spring, a single oak tree produces both male flowers (in the form of catkins) and small female flowers. The fruit is a nut called an acorn or oak nut borne in a cup-like structure known as a cupule; each acorn contains one seed (rarely two or three) and takes 6–18 months to mature, depending on their species. The live oaks are distinguished for being evergreen, but are not actually a distinct group and instead are dispersed across the genus.
What family is the oak in?
How many species are there?
How are their leaves arranged?
What is their "fruit"?
Called what
How many seeds are usually in an acorn?
Can there be more than one?
What chemical is in an acorn?
How does that help the tree?
Are all oaks deciduous?
Which species isn't?
Are they a distinct group?
Are there oaks in Australia?
How many types of oaks are in the US?
And in Mexico?
beech family
An oak is a tree or shrub in the genus Quercus (; Latin "oak tree") of the beech family,
600
There are approximately 600 extant species of oaks.
spirally arranged
Oaks have spirally arranged leaves
a nut
 The fruit is a nut
acorn
called an acorn
One
each acorn contains one seed
Yes
each acorn contains one seed (rarely two or three)
tannic acid
the acorns contain tannic acid
helps to guard from fungi and insects
which helps to guard from fungi and insects
No
An oak is a tree or shrub in the genus Quercus (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 600 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably "Lithocarpus" (stone oaks), as well as in those of unrelated species such as "Grevillea robusta" (silky oaks) and the Casuarinaceae (she-oaks). The genus "Quercus" is native to the Northern Hemisphere, and includes deciduous and evergreen species extending from cool temperate to tropical latitudes in the Americas, Asia, Europe, and North Africa. North America contains the largest number of oak species, with approximately 90 occurring in the United States, while Mexico has 160 species of which 109 are endemic. The second greatest center of oak diversity is China, which contains approximately 100 species. 
evergreen species
 evergreen species
No
 but are not actually a distinct group and instead are dispersed across the genus.
unknown
unknown
approximately 90
 the largest number of oak species, with approximately 90 occurring in the United States
160
while Mexico has 160 species