Transcript Cell types, plant cells, tissues and organ - 2D-Quad3-2010

Lesson 6
Plant cells, Tissues, and Organs
A- What you need to know?
A1. How can cell differentiate from one another?
A2. What are meristem cells? Where are they?
A3. What is tissue?
A4. Organize cells, tissues, organs, organism
according to complexity
A5. Basic structures of plant organs (leaves,
stem, root and flower) + main functions
A6. Types of tissues in plants
B- Cell shapes
and sizes
B1.Do all cell have
the same shape
and size?
B2. No
B3. Expect these
cells to have the
same functions?
B4. Not likely
C-The reasons for the differences in
cells
C1. Result of mitosis?
C2. Two identical new cells with same
set of DNA
C3. But cells don’t have the same
functions and shapes (from previous slide). What
causes the differences?
C4. The reason: cell differentiation and
cell specialization
C- The reasons for the differences in
cells (cont.)
C5. As cells differentiate (=making itself
different from other cells), it becomes
specialized in a particular functions
C6. Cells are specialized based on?
C7. - the proteins they contain
C8. What code for proteins?
C9. - answer: genes code for proteins
C- The reasons for the differences in
cells (cont.)
C12- But aren’t all cells have the
same set of genes as a result of
mitosis, how are different proteins
are made in different cells?
C11. Answer: - not all genes are
turned on in any given cell
- One set of genes is
turned on in one cell type
while another set of
genes is turned on in
another cell type.
D- Cell, tissue, organ and systems
D1. Cells = smallest units of life
D2. Tissue = group of specialized cells
D3. Organ = combination of several types
of tissue working together to perform a
specific function
D4. Organ systems = combination of
many organs working together to keep
the organism alive
D5. Organism = contain all the above
EOrganizing
cells,
organs,
organism,
tissue with
increasing
complexity
An organism (e.g. a person, a plant,
etc)
FOrganizing
cells,
tissues,
organ,
organism in
plant
F1. Leaves, stem,
root and flower are
plant organs
Plant
cells
Plant tissues: dermal,
ground and vascular
bundles
Leaves
Stem
Root
G- Whole plant = the organism
G1. What is it
that help plants
push upward,
downward and
outward?
http://www.progressivegardens.com
/knowledge_tree/plantphys.html
H- Specialized cells and tissues in
plants
H1.Meristems are cells that
form specialized cells in plants
H2.These meristem cells
constantly produce new cells,
which then become specialized
and form 3 different types of
tissues in plants (next slide)
H3.Plants can push upward,
downward thanks to meristems
- Meristems at root tip
I-Where can we find meristems in plants?
I1. Root tip (seen in previous slide)
I2. Terminal (end) and lateral (side) bud
J-Meristem cells make all of these following tissues systems
groups of
epidermal cells
form DERMAL
TISSUES
Epidermal cell
Meristem cells
Photosynthetic cells
Support
cell
(thick
cell
wall)
GROUND
TISSUE
VASCULAR
TISSUE
Show Cell division + differetiation
+specialization occur
K- 3 types of tissues in plant
Types of Tissue system and
functions
1.Dermal Tissue System
• protection
• prevention of water loss
2.Ground Tissue System
• photosynthesis
• food storage
• regeneration
• support
• protection
3. Vascular Tissue System
• transport of water and minerals
• transport of food
Tissue location
Bark
Leaf surface
Leaf
root
Stem
Root
L- What are the organs in
plants?
L1- Leaves, stems, root and flower
M- Plant organs- The leaf
M1. Which process
occur here?
M2.Photosynthesis
M3. Why is leaves thin
and flat?
M4. Thin so light can
penetrate
M5. Flat for a large
surface area so
photosynthesis can
take place efficiently
M- The leaf (cont.)
M6. Describe photosynthesis in
leaves with chemical equation?
CO2 + H2O  C6H12O6 + O2
M7. Any excess glucose in leaves is
stored as starch
M8. Starch is insoluble in water
N - Leaf cross
section
N1-A
guard cell
and its
stomata
Upper leaf
Function
1. Cuticle
prevent water from evaporate
2. Epidermis tissue
protect leaf, not perform photosynthesis
Middle leaf
Function
1. Mesophyll tissue
consists of palisade tissue cells and spongy
parenchyma cells
1a. Palisade tissue
cells
perform photosynthesis, have lots of chloroplasts inside.
Lots of mitochondria as well for cellular respiration
1b. Spongy
parenchyma
below palisade tissue. Contain loosely pack cells. This
creates spaces like a sponge to store water vapour,
O2, CO2 for photosynthesis
4. Vascular bundles
made up of xylem and phloem; form veins that acts like
water and nutrient pipes that deliver to all cells in leaf
Lower leaf
1. Epidermis
Function
also the layer that protects leaves. Contain guard cells
Every 2 guard cells creates an opening called stomata
which allow CO2 to enter leaves and O2 and water
vapour to exit the leaves. Many guard cells across
O- Chloroplast: where PS occurs
P- Zoom in at the chloroplast
P1.Chloroplast: a double membraned organelle
contains many light trapping molecules called
chlorophylls
P2.Photosynthesis occurs at the thylakoid membrane
Q- Leaf adaptation
Giant water lily
Dessert Cacti
Carnivorous plant
Venus fly trap
R-The Stem (or shoot)
R1. 2 main functions:
physical support +
transportation of water,
nutrients and sugar
R2. Vascular bundles:
consists of xylem (tissue)
and phloem (tissue) that
helps transport water and
nutrients in plants
R3. Grouping xylem and
phloem tissues together
helps strengthen the
stem.
S- Vascular bundles =
xylem + phloem
S1. Xylem cells: are dead
tubule cells, stacked end-to-end
-hollow pipes transport water
from roots to other parts of
plant
Stem cross
section
S- Vascular bundles =
xylem + phloem (cont)
S2. Phloem cells:
S3. living tubule cells, also
joined end to end but smaller
diameter than xylem.
S4. Transport sugars from
leaves to other parts
S5. Have porous cell wall that
allows materials to pass
through between neighbouring
cells
Stem cross
section
T- Stem (cont.)
T1. Terminal bud: where most active growth
occurs
T2. Lateral bud: is dormant (inactive); but can
start to growth into new branches, leaves and
flowers.
U- The root
U1. Function:
U2 - anchor plant
U3 - take up water and
minerals from soil
U4 - storage place
U5- prevent soil
erosion
U6- Also contain xylem
and phloem used to
transport water,
nutrients through
plants
U- Root (cont.)
Components
of root
Location/functions
Cortex cells
do not have chlorophyll.
Cells can store starch
Endodermis
Cell layer outside the
pericycle.
Their membranes regulate
types and amounts of
materials root can absorb
Pericyle
Outermost layer of the
vascular bundles.
Contain meristem cell
that can form branch root
Root cap
helps protect meristem cells
at root tip from damages
Root hair
absorb water
Cortex
V- Types of roots
1 -Taproot:
V1. Can reach far underground for
water
V2. Anchor plant firmly in the ground
V3. Plants with this type of root are
harder to pull out
- E.g. dandelion root
2. Fibrous root:
V4.Near soil surface
V5.Cover large surface area to look
for water right under soil surface
V6. helps prevent soil erosion and
landslides.
W-Flower= plant reproductive organ
W1.Flower contains very
light weighed pollens
(producing sperms) and
ovules (producing
eggs)
W2. Pollination (=
fertilization): sperms of
one plant meet the
eggs of another plant
W3. How do most plant
accomplish pollination?
Insect, wind, human
W4. Plants that do not have flowers reproduce asexually
from pre-existing stem or root. Eg. Banana, strawberry
X- Plant under attack
X1. By whom?
X2. Viruses, bacteria,
fungi and insects
X3. Not all plant diseases
are harmful (from a
human’s perspective)
X4. Eg. Rembrandt tulips
have stripes pattern
thanks to virus infection
Tobacco mosaic
virus
Y-Plant gall
Y1. Gall in plant = tumour in animal
Y2. Abnormal group of cells keeps on dividing
and form gall.
Y3. Caused by attack of insects, fungi, bacteria
and viruses
Y4. Galls do not spread to other tissues like
animal tumours do
Z- Is plant a passive victim?
Z1.Plants under attack protect
themselves and neighbouring
plants by releasing volatile
chemicals into the air around
them
Z2. Example: tomato release
chemicals into the air when
being eaten by hornworms.
These chemicals call a parasitic
wasp to lay eggs into the body
of the hornworms.
Z3. The eggs hatch and feed on
the caterpillar
AB-Case study- Eliminate wheat rust
AB1.Wheat rust caused by fungi
that mutate frequently
AB2.Traditional treatment uses
fungicide which kills the bad
fungi but also beneficial fungus
AB3.Australian scientists
discovered 2 genes that could
help wheat combat this disease.
What technique you’ve learnt
can help treat wheat rust by
using the 2 newly discovered
genes?
Wheat rust
IN CLASS ACTIVITY
• Do questions 1 & 2 page 67 in
class for the case study
• Also Question 1-8 p 69