AP Biology Plant Unit
You should know:
Chapter 29
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the four key traits that land plants share with charophyceans
the five key traits that are present in nearly all land plants but are absent in
charophyceans
that the origin of land plants occurred approximately 475 million years ago
that mosses, liverworts, and hornworts are collectively known as bryophytes, are
the oldest group of land plants and lack vascular tissue These plants reproduce
by spores.
that the gametophyte (n) generation is dominant and the sporophyte (2n)
generation is reduced in bryophytes. The opposite situation is true for the three
groups of land plants.
The generalized sequence of alternation of generation in bryophytes (haploid,
diploid, archegonia, antheridia) p. 581
The reduced gametophyte protects the female gametophyte from environmental
stresses. (chapter 30)
That seedless vascular plants (Pterophytes) followed the bryophytes and
includes ferns, horsetails, whisk ferns, and club mosses These plants reproduce
by spores and are 420 million years old.
That horsetails and club mosses produce spores in strobili and ferns produce
spores in sori.
Nearly all seed plants are homosporous – producing one type of spore, resulting
in a bisexual gametophyte
The modified leaves on these structures are called sporophylls.
Chapter 30
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Megasporangia produce megaspores that give rise to female gametophytes and
microsporangia produce microspores that give rise to male gametophytes.
Microspores develop into pollen grains which contain male gametophytes.
Megaspores develop into a multicellular female gametophyte. Layers of
sporophyte tissue called integuments envelop and protect the megasporangium.
The ovule consists of the megasporagium, the megaspore, and the integument.
p. 593
The ovule develops into a seed, which consists of the embryo, along with a food
supply
In contrast to spores, seeds are more resistant and complex and may remain
dormant for days, months, or years.
Most gymnosperms are conifers, or cone-bearing trees and evolved
approximately 360 million years ago. Some of the exceptions are Welwitschia,
Ephedra, Gnetum, and Gingko biloba. pp. 594-595
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that California has the oldest (Bristle Cone Pine), largest (Sequoia), and tallest
(Redwood) trees in the world (extra credit if you show pictures of yourself
hugging all three)
Most species of pines produce male and female cones In conifers the two types
of spores are produced by separate cones. Conifers are heterosporous.
the parts of a flower p. 598
the life cycle of angiosperms p. 600
The evolution of flowering plants occurred approximately 125 million years ago
Chapter 35
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Example of adventitious roots
The role of xylem and phloem and the tissues present within xylem and phloem
and their corresponding roles p. 719
the role of the root cap, pericycle, cortex, endodermis, and Casparian strip in
roots
the parts of the leaf and their roles p. 725
Chapter 36
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the role of water potential in moving water to the top of trees
how to solve simple problems when given the water potential equation
how water and minerals ascend from roots to shoots through the xylem pp. 746749
how stomata regulate transpiration
Chapter 38
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how double fertilization occurs in angiosperms
Chapter 39
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what a tropism is and how phototropism regulate plant movement
how to describe the role of at least two plant hormones p. 794