6. Plant Photosynethesis
• Photosynthesis is the
process by which plants
make food (sugar or
glucose)
– Sunlight provides energy
– The air provides carbon
dioxide
– Nutrients and water are
absorbed by the roots
– Photosynthesis occurs in the
chloroplast in the leaves
– Sugars are made as food for
the plant and oxygen is
released
Carbon dioxide enters the leaves through
stomata (tiny holes) in the leaves. Oxygen
leaves the same way.
8. Parts of a Plant
• Four basic parts
– leaves
– stems
– roots
– flowers
9. Leaves
• Definition: flattened
outgrowth of stem
• Used for:
photosynthesis,
respiration, and
transpiration
• Produces food
used by the plant
and also store it for
later use
10. Shape and Size of Leaves
• Vary among plants
• Used for identification of plants
11. Leaves: Their Basic Parts
•Leaf Base
•Petiole
•Lamina (blade)
•Midrib
•Veins
•Margins (edges)
13. Leaf Base
•Part attached to the stem or branch
•Protects a bud in its axil
14. Petiole
• Part of leaf that connects the lamina with
the stem (leaf stalk)
•Some time a leaf may not have a petiole,
such leaves are called – Sessile
15. Lamina (blade)
•The flat, expended, and broad part of leaf
•Most important part of the leaf (food
manufacturer)
• Has veins
• Forms structural
framework of
the leaf
16. Midrib
• Large center vein
from which all
other leaf veins
extend
17. Veins
• Systems of tubes
(xylem and phloem)
for the transport of
nutrients and water
– Xylem: ducts that bring
water and minerals
from the roots into the
leaf
– Phloem: ducts that
usually move sap, with
dissolved sucrose,
produced by
photosynthesis in the
leaf, out of the leaf
20. Leaf Arrangement
• Alternate
• Opposite
• Whorled
– arranged in a
circle around the
stem
21. Leaf Types
• Simple leaf:
undivided blade
with a single
axillary bud at the
base of its petiole
22. Leaf Types
• Compound leaf:
blade divided into leaflets
has a single bud at the base of its petiole
– pinnate -- palmate
23. Leaf Types
• Peltate leaves: petioles
that are attached to the
middle of the blade
• Perfoliate leaves: sessile
leaves that surround and
are pierced by stems
39. Stem Functions
• Used for food storage
and reproduction of
plants involving
cuttings
• Green stems
manufacture food just
as leaves do
40. External Stem Structure
• Lenticels:
breathing pores
• Bud scale scars:
indicate where
terminal bud has
been located
previous year
41. Leaf Scars
• Show where leaf
was attached
• Distance between
the two represents
one year of growth
42. 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
43. Roots
• Underground or
above ground
• Functions:
– anchor plant and
hold upright
– absorb water
and minerals
form soil and
conduct to stem
– store food
44. External
• Root Cap
– produces new cells
– protects roots as they
push through soil
• Root Hair
– increases surface area
of roots
– facilitate the
absorption of water
and nutrients
45. Root Structure
• Internal
– similar to stems
– older roots have xylem, phloem and
cambian
46. Type of Root Systems
• Fibrous Roots:
– easier
transplanting
– shorter, smaller,
more compact
Examples of plants
with this root
system are
Banana
Coconut
Rice
Corn
Sugar Cane
All grasses
47. Type of Root Systems
• Tap Roots:
– large central
roots with
shorter,
branching roots
Examples of plants
with this root
system are
Mango
Avocado
Carrots
Tomatoes
Peppers
48. Type of Root Systems
• Aerial Roots:
– hang down in
mid-air and
absorb water
from rainfall
Examples of plants
with this root
system are
Some mangroves
Wild Pine
Orchids
49. Specialized Root Systems
• Stilt Roots:
– grow down from
lateral branches,
branching in the
soil
50. Specialized Root Systems
• Adventitious Roots:
– Grow from
unusual places
on plants such
as stems, leaves
and even fruits
51. Specialized Root Systems
• Stilt Roots:
– grow down from
lateral branches,
branching in the
soil
52. Flowers
• Definition: the seed-bearing part of a
plant, consisting of reproductive organs
(stamens and carpels) that are typically
surrounded by a brightly colored corolla
(petals) and a green calyx (sepals)
• Vary in size, shape, and colors
• Flowering plants are called
angiosperms
53. Flower Structure
• Petals
• Stamen and pistil:
reproductive
organs
• Anther and ovary
• Calyx (sepal):
green leaf-like part
that covers and
protects bud before
opening
54. Petals
• Are actually leaves
• Usually bright colors to attract
pollinating insects
55. Stamen
• Stamens
–male part of
flower
– has two parts
1.filament
2.anther
Anther
Filament
56. Pistil
• Stamens
– female part of flower
– has three parts
1.stigma
2.style
3.ovary
57. Anther
• Anther: sac-like structure on top of
filament, contains pollen
58. Ovary
• Egg cells develop here
• Grows to become fruit
or seedcoat
59. Animals: A Simbiotic Relationship
• 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
60. Types of Flowers
• Complete contains 4 main parts
• Incomplete does not have all 4 main
parts
61. Flower Classification
• Monoecious
– stamens and pistils are found in separate
flowers on the same plant
– ex: Corn
62. Flower Classification
• Dioecious
– stamens and pistils are
found in separate flowers
on separate plant
– ex: Holly
63. Gymnosperms
• Group of non-flowering,
seed-producing plants:
– conifers, cycads, Ginkgo,
and Gnetales
– comes from the Greek
word gymnospermos,
meaning "naked seeds"
– seeds develop either on
the surface of scales or
leaves, often modified to
form cones, or at the end
of short stalks
64. Pteridophyta
• Primitive plant
• Do not produce flowers
or seeds
• Reproduce by spores
• Have xylem and phloem
(making them vascular
plants)
• Have stems, leaves, and
roots
65. SSeeeeddss
A seed is an embryonic plant
enclosed
in a protective outer covering called
the seed coat, usually with some
stored food
70. GGEERRMMIINNAATTIIOONN
Steps:
• Seed coat breaks
• Radicle becomes
root
• Hypocotyl and
epicotyl become
the stem
• First leaves grow
and
photosynthesis
begins
First leaves
Watch the following video https://www.youtube.com/watch?v=oYzXToyEzBU