Chap 2 - Structure and Function of Leaves Flashcards
green, veiny suckers
1
Q
Three Basic Leaf Shapes
A
long and narrow
broad and flat
pine-like or needle-like
2
Q
Name the 4 different leaf arrangements.
A
Opposite, Alternate, Whorled, Rosette/Basal
Opposite - 2 leaves per node
Alternate - 1 leaf per node
Whorled - over 2 leaves per node
Rosette/Basal - several clustered leaves at the plant’s base
3
Q
Leaves orient themselves so each blade is at a roughly ___ angle to the source of _____.
A
90 degree; light
4
Q
Phototropism
A
The GROWTH response of a PLANT stimulated by LIGHT
5
Q
How do leaves turn towards the sun?
A
The darker side of the petiole can twist/turn the leaf as it grows faster than the side exposed to light
6
Q
Simple Leaves
A
One blade per petiole
7
Q
Compound Leaves
A
More than one blade on every petiole
8
Q
Leaf: Blade
A
Flat Portion
9
Q
Leaf: Petiole
A
Leafstalk
10
Q
Leaf: Margin
A
The edge/border of the BLADE
11
Q
Leaf: Veins
A
Carry food and water through the BLADE
12
Q
Leaf: Midrib
A
Large vein running through the BLADE’S center
13
Q
Leaf: Stipules
A
small, leaf-like, PROTECT/cover developing leaves
Petiole
14
Q
Leaf: Buds
A
Contain developing leaf or stem structures
Petiole
15
Q
Bud Scales
A
Cover dormant Buds in Winter
16
Q
Bud-Scale Scars
A
Shows where one season’s growth ended and the other began
17
Q
Leaf Scars
A
Shows where leaves were previously attached
18
Q
Leaflet
A
Small blade on a COMPOUND Leaf
19
Q
Do leaflets have petioles?
A
No, leaflet stalks
20
Q
Each root, stem, leaf, and flower of a plant is an _____.
A
Organ
21
Q
Root System
A
Underground. Anchors.
Absorbs nutrients and stores food!
22
Q
What are the 3 tissue types in most plants?
A
Structural - makes up body/structure
Vascular - Conducts materials through plant
Meristematic - makes new tissue for growth and repair
23
Q
Structural Tissue
A
Makes up the body/structure
24
Q
Epidermal Tissue
A
thin herbaceous plant skin (protects, covers)
usually under a waxy layer (cuticle)
25
Cuticle
Waxy layer covering the Epidermal Tissue
seal in water
26
Cork
outermost woody plant layer
rectangular dead cells, waterproof
27
Parenchyma
Structural Tissue
makes and stores food
variety of shapes - contain vacuoles and chloroplasts
28
Support and Strengthening Tissue
fibers made of THICC-walled cells
Supports roots, stems, leaves (veins and petioles)
short life, protects after death
29
Vascular Tissue
Conducts materials through plants
Expressway/Transportation system
for Sap Conduction
30
Xylem
Takes water and minerals UP from ROOTS to Leaves
31
Tracheids
Vessels
Elongated Cells and
Long Tubes respectively
That Make up XYLEM
32
Phloem
Takes dissolved food from LEAVES DOWN to stem, roots.
33
Sieve Tubes
Elongated Cells that PHLOEM is made of
34
Sap is found where?
In vascular tissue
35
Sap - water with dissolved minerals
From ROOTS to LEAVES
36
Sap - Dissolved food (some water)
From LEAVES to STEM, ROOTS
37
Meristematic Tissue
Produces tissue for GROWTH and REPAIR
Made of thin-walled, rapid dividing cells
38
Apical Meristems
externally on Root and Stem tips
Promotes LONGITUDINAL growth
39
Cambium
INTERNAL growth cells that promote LATERAL growth (width in root, stem)
40
Vascular Cambium
makes NEW Xylem, Phloem Tissue
layered between xylem and phloem in stems, roots
41
Cork Cambium
makes NEW cork tissue
layered under cork
42
3 Main Leaf Parts
Epidermis
Mesophyll
Veins
43
Stomata
leaf pores
lower epidermis
44
Why are Stoma important?
allows in Oxygen for breathing.
Carbon Dioxide for Photosynthesis
Transpiration Regulation (loss of water vapor from stems, leaves)
45
Guard Cells
2 crescent shaped doors that contract to open/close each stoma (leaf pore)
46
Leaf Hairs
cover some plants' epidermis
slow water loss, defend against bugs, excrete toxic substances
47
The Mesophyll
Middle portion of a leaf - Photosynthesis, Parenchyma Tissue
Most photosynthesis happens here
Parenchyma Tissue is abundant
48
Palisade Mesophyll
fence post cells - sometimes multiple layers
small air spaces
49
Spongy Mesophyll
large, odd-shaped cells
Large air spaces
50
The leaves of some dicots and MOST monocots contain ONLY ______ mesophyll.
Spongy
51
Intercellular Air Spaces
Air spaces between palisade and spongy mesophyll cells
Allows air and CO2 to enter so cells can obtain them
52
Venation
vein pattern in leaves
53
Parallel Venation
veins are parallel to each other along the leaf
Monocots
54
Pinnate Venation
1 major vein (midrib) and other smaller branching ones (feather-like)
55
Palmate Venation
Multiples major veins with many more smaller branching ones (finger-like)
56
Veins
Contain Vascular Tissue - Phloem and Xylem
IN Mesophyll Layers
Transports SAP
57
Cell
basic structural unit of all organisms
58
3 Main Plant, Animal Cell Parts
Cell Membrane
Nucleus
Cytoplasm
59
Cell Wall
Made of Cellulose (complex card)
Supports and Protects
Gives the plant its structure
60
Cellulose
Complex carb made of LONG chains of glucose molecules - strong, flexible
Can't be digested by humans, only animals
61
Lignin
In plant Cell Walls of Woody Plants that made them STIFF(er)
62
Cell Membrane
Regulates cell entry/exit, under the Cell Wall
Separates the Cell from its environment
63
Cytoplasm
gelatinous cell fluid
contains organelles and many molecules
64
Chloroplasts
Organelles that are "Chemical Factories"
Use light to manufacture food
Contain Chlorophyll and Thylakoid Stacks
65
Where are Chloroplasts found?
In the Mesophyll layers (mainly Palisade - upper), in guard cells, the stem, and unripe green fruits
66
Chlorophyll
Within Chloroplasts.
Gives green pigment!
Enables the capture of light energy
67
Vacuoles
Large storage structures in cells
Stores food, fluid, minerals
1 or 2 large ones per plant cell
68
Autotrophs
Producers. Make their own food.
69
Heterotrophs
Consumers. Cannot make their own food.
70
Photosynthesis
"Putting together with light." A plant's chloroplasts capture radiant light energy and covert it into chemical food energy,
71
Thylakoids
Stacked, special disks WITHIN chloroplasts (organelle) that have Chlorophyll molecules in their membranes
Hollow
72
Granum (or Grana)
A stack of Thylakoids
73
Chloroplast Stoma
aqueous fluid
74
Chloroplast: 3 Membrane Parts
Outer Membrane
Intermembrane Space
Inner Membrane
75
Thylakoid Membrane
Surrounds each thylakoid, contains Chlorophyll molecules to absorb light!
76
Lumen
A fluid that fills Thylakoids
solution of water, enzymes, ions
77
Stroma Lamellae or Stroma Thylakoids
Connect and maintain distance between Grana (Thylakoid Stacks) within the Chloroplast
78
6CO2 + 6H2O + photons = what?
(carbon dioxide, water, light energy)
C6H12O6 (Glucose) + 6O2 (Oxygen)
79
C6H12O6 (Glucose) + 6O2 (Oxygen) is made by WHAT?
6CO2 + 6H2O + photons = what?
(carbon dioxide, water, light energy)
80
The 2 photosynthesis phases
(that occur simultaneously)
Light Reactions and Dark Reactions
81
Light Reactions
6CO2 + 6H2O + photons = C6H12O6 (Glucose) + 6O2
think WATER
H2O from soil (via Xylem transport) +
CO2 from air (via Stomata + spongy Mesophyll) +
LIGHT Energy >>>
H2O SPLITS into H ions and O;
Oxygen goes to the air
Hydrogen helps made ATP and NADPH (high-energy compounds)
82
Dark Reactions
6CO2 + 6H2O + photons = C6H12O6 (Glucose) + 6O2
Think AIR
CO2 from air + H Atoms = GLUCOSE! (C6H12O6 - simple Sugar)
needed ENERGY from breaking down ATP and NADPH (L reactions) is needed; used to SYNTHESIZE Glucose
83
Cellular Respiration
"Burns" sugars (oxidizes them - adds O) as fuel for energy (stored Glucose to ATP, for example)
84
Oxidizing Sugars
Chemical Reaction that combines Sugars with Oxygen to facilitate Cellular Respiration
85
Only the cells containing ___________ can produce their own _______ through Photosynthesis.
Chlorophyll; Glucose
86
Sucrose
Table Sugar. Transported to the rest of the plant in sap.
Converted from Glucose (Simple Sugar) which can only be produced in cells with Chlorophyll (but ALL cells need energy)
87
Starch
A long, Chain-Like molecule of Glucose Molecules (thousands linked) stuck together for storage
excess sugar/food storage train
88
Sugars, Minerals and Nitrogen (protein ingredient) are GREAT materials for what?
Plant Growth!
89
A CO2 increase or decrease WILL _______ or ______ the rate of Photosynthesis, respectively.
Improve; Impair/SLow
90
In MOST plants, what is the ideal Photosynthesis temp?
15 C and 30 C (60 F and 85 F)
91
Chlorophyll Deterioration
Shorter days mean no new Chlorophyll while the OLD stuff deteriorates.
Thus other hidden pigments become visible.
92
Xanthophyll
Pigment that produces yellowish colors
93
Carotene
Pigment that produces yellowish-orange colors
94
Beta Carotene
A form of Carotene that makes Carrots their color
Can be converted to Vitamin A for people :)
95
Anthocyanin
Pigment that produces bright red, blue, and purple colors
96
Abscission Layer
a special layer of thin-walled Parenchyma (structural tissue - storage type) that forms at the base of leaves (petiole + stem) to detach them
chops off plant organ
97
Cellulase
special enzyme
weakens the the cell walls of the Abscission Layer so the leaf BREAK OFF under its OWN WEIGHT
98
Leaf Scars after Abscission
protective layer of cork cells at the petioles base (pre or post-leaf detachment) that protects the innards
99
Transpiration
process by which plants lose water vapor from their leaves and stems
affected by humidity, temp, sunlight, wind speed, CO2 amount, soil water availability
100
Turgor Pressure
Pressure that water within guard cells produces
More Water = More Pressure (Turgid/swollen guard cells) and open Stomata (leaf pores)
Less Water (fast Transpiration) = Lower Pressure and the Guard Cells CLOSE to slow/reduce water loss
101
Turgid guard cells are what?
Filled with Water (swollen, distended)
102
A high Transpiration rate can cause _______.
Wilting due to plant cells losing their Turgor
103
Temporary Wilting
Transpiration happens faster than roots can absorb soil water
Daytime wilting can be reversed at night when Transpiration is reduced
104
Permanent Wilting
Leaf loss and plant death due to drought, bad soil (dry). Recovery from Transpiration and lack of soil water is difficult
105
Special Leaf
Modified Leaf. Has a special design for a special task.
Internally Leaf-ish, same basic tissue structure, buds form at their bases
Pea Tendrils, Barre; Cactus Spines, Pitcher Plant
106
Tendrils
Leaves or Stems of vines that give them structure via coiling around supports
107
Spines
Protected cactus leaves that have no Chlorophyll
108
Insectivous Plants
Eat insects for nutrients (N for protein building)
Venus flytrap, bladderwort, pitcher plant, sundew
