AP Review
Chapters 29-31,
Fast Facts
There are four main groups of land plants:
bryophytes, pteridophytes,
gymnosperms, and angiosperms
Bryophytes: mosses; distinguished from
algae by advances that allow for life on
land
Pteridophytes: ferns; contain vascular
tissue (transport water and food);
“seedless plants”
Fast Facts
Gymnosperms:conifers; “naked seed” (seeds
are not enclosed in a special chamber)
Seed: consists of a plant embryo packaged
with food and a protective coat
Angiosperms: flowering plants; “container
seed”; most modern-day plants
algal ancestors  bryophytes  vascular
plants  the origin of seeds  the evolution
of flowers
Fast Facts
Charophyceans are the green algae most
closely related to land plants
Several terrestrial adaptations distinguish land
plants from charophycean algae
- growth in length is from apical meristems
- multicellular, dependent embryos
- alteration of generations: gametophyte
and sporophyte
Fast Facts
Fast Facts
Fast Facts
Adaptations for water conservation:
- formation of a cuticle
- stomata contain guard cells
Adaptations for water transport:
- xylem: carry water and minerals up
from root
- phloem: distribute sugars and amino
acids throughout the plant
Fast Facts
The gametophyte is the dominant
generation in the life cycle of bryophytes
Modern vascular plants include ferns
(pteridophytes), gymnosperms, and
flowering plants (angiosperms)
Differ from bryophytes
- contain phloem and xylem
- dominant sporophyte generation
Fast Facts
Fast Facts
Seed plants are vascular plants that
produce seeds
The developing embryo is encased in a
protective seed coat and supplied with
its own source of food (endosperm or
cotyledons)
Fast Facts
Fast Facts
Seeds allow the embryo to be moved
away from the parent by wind, water,
and animals
Seed plants are not tied to water for
fertilization; pollen grains do not need to
be transported by liquid
Fast Facts
Gymnosperms lack enclosed chambers
in which seeds develop; instead, seeds
develop on the surfaces of specialized
leaves called sporophylls.
Phylum Anthophyta:
- all angiosperms are placed in one
phylum
Two classes: monocots and dicots
Fast Facts
- have vessel
elements for
water transport
instead of
tracheids; speed
water transport
through the plant
Fast Facts
Fast Facts
All fungi are eukaryotic; most are
multicellular
mycete = fungi
Fungi differ from plants in nutritional
mode, structural organization, growth,
and reproduction
Fungi are heterotrophs that acquire their
nutrients by absorption
Fast Facts
The bodies of fungi
are constructed of
tiny filaments called
hyphae
- the hyphae are
divided into cells by
cross-walls, or
septa
- cells walls are
made of chitin
Fast Facts
Lichens
- symbiotic relationship of millions of
photosynthetic microorganisms held in a
mesh of fungal hyphae
- the alga provides the fungus with food.
The fungus provides a suitable
environment for growth
Fast Facts
Fast Facts
Mycorrhizae
- mutualistic
association of
plant roots and
fungi
- responsible for
making nutrients
able to be
absorbed
Sample Questions
Discuss the adaptations that have
enabled flowering plants to overcome
the following problems associated with
life on land.
a) The absence of an aquatic
environment for reproduction.
b) The absence of an aquatic
environment to support the plant body
c) Dehydration of the plant
Fast Facts
Plants are made up of two main systems:
the root system and shoot system
Monocots have fibrous roots: mat of thin
roots that spread out below the soil
surface
Dicots have a taproot: one large vertical
root that produces lateral branch roots
Fast Facts
Stem
- an alternating system of nodes (place
where leaves are attached) and
internodes (the stem between the
nodes)
- apical dominance: growth focuses on
the terminal bud; inhibits the axillary bud
Fast Facts
Leaves
- main photosynthetic organ of plants
- consist of a flattened blade and a
petiole (stalk that join to the node of the
stem)
- monocots have parallel veins in leaves
- dicot leaves have a multi-branched
network of veins
Fast Facts
Plant organs are composed of three
tissue systems: dermal, vascular, and
ground
Dermal tissue
- single layer of tightly packed cells that
covers and protects all young parts of
the plants
- for the cuticle
Fast Facts
Vascular tissue
- involved in the transport of materials
between the root and the shoot
- xylem: moves water and dissolved
minerals upward from roots
- tracheids and vessel elements
are elongated cells that are dead at
functional maturity
Fast Facts
Fast Facts
- phloem: moves food made by leaves
to the roots
- sieve-tube members transport
sucrose and other organic materials
- sieve plates help move fluid from
cell to cell
- companion cell: assist the STM
Fast Facts
Ground tissue
- tissue that is neither
dermal nor vascular
- in dicots, divided into
the pith (internal to
the vascular tissue)
and the cortex
(external to vascular
tissue)
- photosynthesis,
storage, and support
Fast Facts
Plant tissues are composed of three basic
cell types: parenchyma, collenchyma,
and sclerenchyma
Parenchyma cells
- have 1o cell walls, but lack 2o
- typical plant cell; least specialized
- perform most metabolic functions of
the plant
Fast Facts
Collenchyma cells
- thicker 1o cell walls
- support young parts of the plant shoot
- provide support without restraining growth
Sclerenchyma cells
- support; form thick 2o cells that are
strengthened by lignin
- dead at functional maturity
- ex. xylem cells
Fast Facts
Vascular tissue runs through the stem in
strands called vascular bundles
- surrounded by ground tissue
In dicots, the vascular bundles are
arranged in a ring, with the pith inside
the ring, the cortex is outside
In monocots, the vascular bundles are
scattered throughout the ground tissue
Fast Facts
Fast Facts
Tissue organization of leaves
The epidermis is composed of tightly
interlocked cells
- stomata: tiny pores that allow for gas
exchange w/ the help of guard cells
The ground tissue is sandwiched between
the upper and lower epidermis in the
mesophyll
Fast Facts
- the mesophyll consists
of parenchyma cells
w/ chloroplasts
The vascular tissue also
flows through the leaf
from the stem
- contains the xylem
and phloem
Fast Facts
Differences in water potential drive water transport in
plant cells
Osmosis: the net uptake or loss of water by a cell
Water potential: the combined effect of solute
concentration and pressure.
- psi (Y)
- water will move from the solution with the higher
water potential to the solution with the lower water
potential
Fast Facts
Bulk flow: the movement of fluid driven
by pressure
Root pressure: water flows in from the
root cortex, generating a positive
pressure that forces fluid up the xylem
Root pressure causes guttation: when
more water enters leaves than is
transpired and the excess is forced out
Fast Facts
Pulling up xylem sap: TranspirationCohesion-Tension Theory
Transpiration
-when stomata open water exits the leaf
- move from [high] to [low]
Cohesion
- water molecules will bond to each
other with hydrogen bonds
Fast Facts
Hormones: chemical signals that
coordinate the parts of an organism
Tropism: any growth response that
results in curvatures of whole plant
organs toward or away from stimuli
Phototropism: the growth of a shoot
toward light
Fast Facts
Auxin (IAA)
- any chemical substance that promotes
the elongation of coleoptiles
- moves from the shoot tip down to the
base of the plant
Cytokinins
- stimulate cytokinesis, or cell division
Fast Facts
Gibberellins
- stimulate growth in the stems and leaves,
but not in the roots
- stimulates cell elongation and division
Abscisic Acid
- slows down growth
- seed dormancy: high levels of ABA inhibit
germination; only when the ABA is
inactivated will the seed germinate
Fast Facts
Ethylene
- produced by plants in response to
environmental stresses
- also occurs in fruit ripening and
programmed cell death
Sample Questions
Angiosperms (flowering plants) and vertebrates
obtain nutrients from their environment in
different ways: (A) Discuss the type of nutrition
and the nutritional requirements of
angiosperms. (B) Describe 2 structural
adaptations in angiosperms for obtaining
nutrients from the environment. Relate structure
to function. (C) Interdependence in nature is
evident in symbiosis. Explain two symbiotic
relationships that aid in nutrient uptake, using
examples from angiosperms.