A quick look at the parts of a plant.

1. Parts of the plant and
their functions

2. Importance of plants
• Without plants life on earth
would not exist

3. Plants:
• Primary source of food for
people and animals
• Produce oxygen
• help to keep us cool
• renew the air

4. Plants:
• slow wind speed
• provide a home for wildlife
• beautify surroundings
• perfume the air
• furnish building materials and
fuel

5. Parts of a plant
• Four basic parts
– leaves
– stems
– roots
– flowers

6. Leaves
• the food factory of the plant
• produce the food used by the
plant or stored for later use

7. Shape and size of leaves
• vary among plants
• used for identification of plants

8. Leaf arrangement
• alternate
• opposite
• whorled
– arranged in a circle around the
stem

9. External leaf structure
• petiole - leaf stalk
• leaf blade (leaf)
– has veins
– forms structural framework of
the leaf

10. Midrib
• large center vein from which all
other leaf veins extend

11. Margins
• edges of leaves
• assists in plant identification

12. Internal leaf structure
• epidermis
– skin of the leaf
– single layer of cells
– protects leaf from loss of too
much moisture

13. Guard Cells
• open and close the small pore
on the underside of the leaf

14. Stomates
• allow the plant to breathe and
transpire
– give off moisture

15. Chloroplasts
• contain chlorophyll
• located inside the food making
cells

16. Photosynthesis
• process by which CO2 and
H2O in the presence of light are
converted to sugar and oxygen

17. Chemical formula
• 6CO2 + 6H2O
• -----> in reaction with sunlight
and chlorophyll ------>
• C6H12O6 (glucose) + 6O2

18. food
• manufactured in the leaves
moves downward through the
stem to the roots
– used by the plant
– stored in stem or root and leaf in
the form of sugar, starch or
protein.

19. Respiration
• plants respire 24 hours a day
• consume O2 and give off CO2
• plants produce more O2
through ps. Than they consume
during respiration and growth.

20. Stems
• have two main functions
– movement of water and minerals
from the roots upward and
movement of manufactured food
down

21. Stem functions
• support of leaves and
reproductive structures

22. Stems also
• used for food storage and
reproduction of plants
involving cuttings
• Green stems manufacture food
just as leaves do

23. External Stem Structure
• lenticels- breathing pores
• bud scale scars-indicate where
terminal bud has been located
previous year.

24. Leaf Scars
• shows where leaf was attached
• Distance between the two
represents one year of growth.

25. Internal Stem Structure
• phloem- bark, carries
manufactured foods down.
• Xylem- wood, carries water and
minerals up.
• Cambium- separates the 2 and
produces all new cells.
• Characteristic of dicots

26. Internal Stem Structure
• dicot- dicotyledon, a plant with
2 seed leaves

27. Monocot
• Monocotyledon - a plant with
one seed leaf.
• Have vascular bundles, contain
both xylem and phloem in each
small bundle

28. Monocot
• stems have no cambium
• cells enlarge to create size of
mature stem

29. Economic Importance
• food
• building materials

30. Roots
• Usually underground
• functions:
–anchor plant and hold upright
–absorb water and minerals
form soil and conduct to stem
–store food, & propagation

31. Root Structure
• internal
–similar to stems
–older roots have xylem,
phloem and cambian

32. external
–root cap
• produces continuous supply
of new cells
• protects roots as they push
through soil

33. Structure
• root hairs
–absorb moisture and minerals
• small roots

34. Functions other than water
and mineral absorption
• cash crops for food
–carrots
–beets
–radishes
–sweet potatoes
• propagation

35. Type of root systems
• fibrous-grasses
–easier transplanting
–shorter, smaller, more
compact
• lap root-carrot
–longer and fewer roots

36. Flowers, Fruits, and Seeds
• pollination- color of flower attracts
insects to fertilize flower
– beginning of fruit and seed formation
• fruits and seed are attractive to birds
who eat and spread seeds.
– Reproduces plant
– some seeds carried on animals coats

37. Parts of the Flower
• differ in size, shape, and color,
some basic parts
• sepal
–green leaf-like part, covers
and protects bud before
opening

38. Petals
• are actually leaves
• usually bright colors to attract
pollinating insects.

39. Parts of the Flower
• stamens
–male part of flower
–has two parts
• filament-stalk

40. Anther
• anther- sac-like structure
on top of filament,
contains pollen

41. Parts of the Flower
• Pistil - female part
• in the center of flower
• has three parts

42. Pistil
• three parts
• stigma - top - sticky
• style - tube leading from stigma
to ovary

43. Ovary
• egg cells develop here
• grows to become fruit or
seedcoat

44. Types of Flowers
• complete
–contains 4 main parts

45. Incomplete
• does not have all 4 main parts

46. Perfect
• has stamens and pistils

47. Imperfect
• lacks stamens or pistils

48. Types of Flowers
• monoecious
–stamens and pistils are found
in separate flowers on the
same plant
• ex: Corn

49. dioecious
• male or staminate flowers
found on one plant, female or
pistilate flowers on another
plant
• ex: holly