Title: Plant Adaptations
1Plant Adaptations
- 4th Grade Living Systems
- By Brandi Crouch
2In drier, temperate deciduous forests a thick
bark helps to limit moisture evaporation from the
trees trunk.
3Tropical rainforests have high humidity, and most
trees have a thin, smooth bark. This is
probably because the trees to not need to protect
against dryer conditions. The smoothness of the
bark may also make it difficult for other plants
to grow on their surface.
4Lianas are climbing woody vines that drape
rainforest trees. They have adapted to life in
the rainforest by having their roots in the
ground and climbing high into the tree canopy to
reach available sunlight.
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6Epiphytes are plants that live on the surface of
other plants, especially the trunk and
branches. They grow on trees to take advantage
of the sunlight in the canopy.
7Epiphytes This tree has Bromeliads and mosses
living on the surface of its bark.
8The leaves of Bromeliads form a vase to hold
water. The pineapple is an example of a
bromeliad.
9Another bromeliad.
10Rhizophora In deltas and along ocean edges and
river estuaries, trees have adapted to living in
wet, marshy conditions. These trees, called
mangroves, have wide-spreading stilt roots that
support the trees in the tidal mud and trap
nutritious organic matter.
11Desert plants have adapted to the extremes of
heat and aridity by using both physical and
behavioral mechanisms, much like desert animals.
Xerophytes, such as cacti, usually have special
means of storing and conserving water. They often
have few or no leaves, which reduces
transpiration.
12Xerophytes adaptations 1. Thick cuticle. 2.
Stomata hidden in crypts or depressions in leaf
surface (less exposure to wind and sun). 3.
Reduction in size of transpiration surface (lower
leaf only). 4. Increased water storage. 5.
Thicker leaves and stems, or leaves reduced in ,
or leaves drop off during dry season. 6. Leaves
covered with silvery hairs (creates wind break
light reflective surface). 7. Deep taproots or
wide spreading fibrous roots near the soil
surface.
13Phreatophytes are another group of plants that
have adapted to arid environments. Phreatophytes,
like the mesquite tree, have adapted to desert
conditions by developing extremely long root
systems to draw water from deep underground near
the water table.
14The Creosote Bush is one of the most successful
of all desert species because it utilizes a
combination of many adaptations. Instead of
thorns, it relies for protection on a smell and
taste wildlife find unpleasant. It has tiny
leaves that close their stomata (pores) during
the day to avoid water loss and open them at
night to absorb moisture. Creosote has an
extensive double root system -- both radial and
deep -- to accumulate water from both surface and
ground water.
15Some plants, such as the Ocotillo, survive by
becoming dormant during dry periods, then
springing to life when water becomes available.
The Ocotillo also has a waxy coating on stems
which serves to seal in moisture during periods
of dormancy.
16Another example of plants that utilize dormancy
as a means of evading drought are bulbs, members
of the lily family. The tops of bulbs dry out
completely and leave no trace of their existence
above ground during dormant periods.
17The Desert Lily is found at a depth of 18 inches
or more. Adequate winter rains can rouse it to
life after years of dormancy.
18Desert plants must act quickly when heat,
moisture and light inform them it's time to
bloom. Ephemerals send out flower stalks in a
few days. Ephemerals such as the Desert Sand
Verbena usually germinate in the spring following
winter rains. They grow quickly, flower and
produce seeds before dying and scattering their
seeds to the desert floor.
19The Desert Paintbrush is another ephemeral that
quickly blooms and scatters its seeds when it is
active.
20Supportive adaptations many plants have
developed adaptations that help them be more
supported in order to grow taller and stronger.
Some tropical trees have buttress roots, which
are roots that come out from the lower part of
the trunk and grow into the ground.
21Prop roots Some trees grow in very unstable
soil, and the complex prop root system helps keep
the tree stable in an unstable environment. You
can find an example of prop roots when looking at
red mangroves.
22Prop roots on corn.
23Epiphytes and vines also have special roots that
help them grab onto a trees bark and stay put.
24Defensive adaptations Plants as we know have
evolved ways to defend themselves by using sharp
spines, thorns or hairs cellulose that makes
them hard to digest, or creating toxic
chemicals. Another unusual way some plants have
evolved to defend themselves is through mimicry -
that is they evolve to look like another plant
that is poisonous and animals are fooled into
believing that they are poisonous.
25Because weather conditions in the arctic and
alpine tundra are unpredictable, plants need to
adapt to all sorts of weather. Being close to the
dark, warmth-absorbing soil helps to keep plants
from freezing.
26Instead perennials are more hardy of a plant for
the tundra. They are plants which do not die in
the winter because they keep their leaves, shoots
and sometimes just roots in the ground. They
quickly grow when the short growing season
starts.
27Another way plants have adapted is by how their
seeds are dispersed. Some seeds hitch a ride on
passersby using tiny hooks that snag on fur or
clothing, only to be brushed off later far from
the parent plant.
28Other plants, like the dandelion have seeds
better adapted to be caught by the wind and
transported to another location.
29The seeds of maple trees are also very
aerodynamic. They mimic wings.
30Aquatic plants like this fringed water lily have
not needed adaptations for strengthening
themselves. They are supported by the water they
live in. They also do not need as many roots
since they live in the water.
31Many aquatic plants have very specialized leaf
shapes. The submerged leaves are often very
divided. This has the advantage of creating a
very large surface area for absorbing water and
for photosynthesis.
32Pitcher plants (nepenthes) are named after an
unusual adaptation. They have a structure shaped
like a pitcher or vase that acts as a trap. The
trap contains a fluid that the plant produces.
This fluid is used to drown the prey. The lower
part of the trap contains glands which absorb
nutrients from captured prey. Thats right!
Pitcher plants are carnivorous.
33There is no doubt that tropical pitcher plants
(Nepenthes) eat prey they attract it, kill it
and absorb the products of digestion. -June
2000, The Enduring Controversies Concerning the
Process of Protein Digestion in Nepenthes
(Nepenthaceae), International Carnivorous Plant
Society Newsletter. http//www.carnivorousplants.o
rg/cpn/samples/Science292Digest.htm