Plants - peelschools.org


They’re green.






They can’t move.


Why are plants green?



CHLOROPHYLL


Pigment used for photosynthesis



TWO main systems:



Shoot system


Stem, leaf, flower


Root system


Roots


Unlike animals, which are made up of many
systems


Plants can make their own food (no need for
digestive or musculoskeletal system to obtain
food)



But they still need to:


Exchange gases


Move water and nutrients within their bodies


Reproduce


Appr
. 75% of modern medicines come from
plants!



Examples:


Aspirin (Birch bark)


A tree sap that speeds healing


A compound that treats malaria



Right now many plants species are disappearing
before they can be studied.


Absorb water and minerals, store food,
anchor plant



What are some root vegetables? (The ones
where we eat the root, and not the shoots.)



2 main functions:



Conduct photosynthesis


Where?


How? Which organelle is involved?


Which leaves do we eat?



Produce flowers


What are flowers for?


Pollen = plant sperm


Ovary = contains eggs


After pollination (fertilization of eggs by pollen),
seeds are formed. Sometimes surrounded by
fruit. What might a fruit be for?


Occurs with the help of wind or animals.


Ex. insects, bats, birds


Trunks of trees



Contains vascular tissue connecting leaves
flowers, fruits to roots



Sugar cane, wood/paper, cork, linen (i.e.
COTTON)


3 main types:



Dermal tissue system


Outer surfaces of plant parts



Vascular tissue system


Tissues that transport water and nutrients



Ground tissue system


All other structures

Epidermal tissue
–

layer of cells covering all non
-
woody surfaces
of plant



Periderm

tissue
–

tissues that produce bark


Xylem:


Transports water and minerals UP from roots to
stem and leaves


Mature cells not alive



Phloem:


Transports nutrients, sugars, hormones, and
water throughout the plant; UP and DOWN


Mature cells alive


Meristematic

cells


Undifferentiated plant cells that can form any
kind of specialized tissue


Located at tips of roots and shoots (areas of rapid
growth)


Xylem rings show each
year’s growth


Outer lateral
meristem

(cork cambium)


Inner lateral
meristem

(vascular
meristem

=
makes new phloem)


There are lots of fields that study plants.



Example


Ethnobotany

–

the study of how indigenous (native)
plants are used by different cultures


Economic botany
-

plants with commercial
importance. Economic botany includes the study of
harmful and beneficial plants and plant products.


Biotechnology
–

genetic engineering of plants


Natural resource management
–

responsible use of
and protection of natural resources