EXAM 4 OVERVIEW Flashcards
1
Q
Autotrophs
A
-self-feeding
-use carbon from simple substances to make organic compounds
-usually photosynthetic but can be chemotrophs
-Algae, plants, some prokaryotes
2
Q
Heterotrophs
A
-other-feeding
-use carbon from other organic sources to make organic compounds
-gets energy from organic compounds
-animals, fungi, some prokaryotes, and protists
3
Q
What part of the plant does photosynthesis
A
chloroplasts
4
Q
shoot system of the plant
A
made up of stem, leaves, and reproductive organs
5
Q
root system of the plant
A
typically everything underground, made up of roots
6
Q
cuticle of the leaf
A
waxy protective layer
prevents water loss
7
Q
epidermis of the leaf
A
cells that make the cuticle
protect the plant, similar to skin
8
Q
stoma or stomata of the leaf
A
hold to allow air in and out
contains guard cells
9
Q
mesophyll of the leaf
A
middle of the leaf
purpose is to do photosynthesis
10
Q
palisade mesophyll of the leaf
A
long tightly packed cells
11
Q
spongy mesophyll of the leaf
A
larger region less densely packed and does less photosynthesis
12
Q
vascular tissue of the leaf
A
xylem and phloem running through
stem and root
usually non-photosynthetic
specialize in transport
13
Q
What is needed for photosynthesis
A
sunlight, water, air (CO2)
14
Q
Plants lose several 100 water molecules for each CO2 molecule that is fixed by photosynthesis because
A
the concentration gradient is many times larger for water than CO2
15
Q
How does the leaf regulate water loss
A
Guard cells within the stomata regulate water loss. Plants use these to open/close the stomata
-use pumps going into cell
-use channels
-swell and deflate like water wings (turgid and limp)
16
Q
What happens when the stomata is open
A
the stomata opens to do photosynthesis
17
Q
What happens when the stomata is closed
A
The stomata closes to conserve water
18
Q
Where does the dry weight of the plant come from
A
air
19
Q
what happens in photosynthesis
A
air + water + energy yields sugar + oxygen
20
Q
what are the two parts of photosynthesis
A
light reactions and the calvin cycle
21
Q
what is the input of light reactions
A
sunlight, NADP+, ADP, H2O
22
Q
what is the output of light reactions
A
ATP, NADPH, O2
23
Q
light reactions consists of two interconnected systems; what do they do
A
one makes ATP and the other makes NADPH which are used to make carbs/sugars in calvin cycle
24
Q
where do light reactions occur
A
in the chloroplast thylakoid membrane
25
where does the calvin cycle take place
in the stroma of the chloroplast
26
what happens overall in the calvin cycle
3 step process: fixation, reduction, regeneration
takes in CO2 and makes sugars
27
what occurs in the fixation step of the calvin cycle
add CO2 to carbon molecule and fixes carbon with RuBisCO, results in 2 3 carbon molecules, then CO2 goes to organic molecule 3PGA
28
what occurs in the reduction stage of the calvin cycle
3PGA is reduced to G3P
-uses ATP and NADPH
-remove 1 G3P: G3P is main output of calvin cycle
29
Regeneration
remaining 5 G3P is used to regenerate RuBP
this needs more ATP and allows the cycle to start over
30
sugar synthesis
G3P from Calvin Cycle (3 carbon building block for sugars)
requires NADPH, ATP
occurs in the cytoplasm
sucrose and other molecules made from these
31
what are the thylakoids in the chloroplast
flattened sacs
32
what are the granum in the chloroplast
stack of thylakoid
33
what is the stroma within the chloroplast
liquid matrix
34
Chlorophyll reflects..... and absorbs....
chlorophyll reflects green light and absorbs red and blue wavelengths
35
antenna complex
where the chloroplasts are grouped!
- electron excited by light energy
- energy transferred from chlorophyll to chlorophyll ending up at reaction center
-reaction center donates an electron to start an ETC
- overall, it absorbs light and transfers energy to electrons
36
reaction center
specialized chlorophyll that loses its electrons
37
photolysis of water (light reactions)
splitting water
-reaction center chlorophyll left without an electron
-steals an electron from water (oxygen evolving complex)
- water left without an electron (oxidized, water split into H+ ions plus O-, O- combines with another O- to make O2)
- O2 given off as waste gas and build up of hydrogens on the inside of the thylakoid membrane
moves electrons on to PS2
38
photosystem 2 (light reactions)
MAKES ATP & makes the H+ gradient
-ETC similar to ETC
- Makes H+ from H2O
- H+ is pumped from stroma to thylakoid lumen
- ATP synthase used H+ gradient to make ATP
39
Photosystem 1 (light reactions)
MAKES NADPH
40
what does a z-scheme show
drawing of the energy of the electrons
x-axis: proteins
y-axis: energy of electron
actually looks like an N
41
C3 photosynthesis
NORMAL PHOTOSYNTHESIS
Grabs CO2 from the spongy mesophyll for the Calvin cycle
42
Photorespiration
BAD ROUTE
RuBisCO takes O2 instead of CO2 so RuBP has to be regenerated
Happens more when stomata are closed (more O2)
Requires ATP to try again meaning energy intensive so its bad for the plants
43
C4 fixation
Way to get around photorespiration
Separates the fixation from rest of photosystem by SPACE AND ANATOMY; HOT CONDITIONS
- Bundle sheath cells surrounding the vascular tissue
- CO2 captured by PEP carboxylase to form 4 C molecules
44
CAM photosynthesis
Way to get around photorespiration
Separates fixation by TIME
BEST FOR PREVENTING EXCESS WATER LOSS; DRY CONDITIONS
-Night: stomata open, loses water, gains CO2, stores CO2 as a C4 acid in vacuoles
- Day: stomata closed, release CO2 to calvin cycle
45
Zombie Plants
Cut off roots and put into poison
- Plant dies but anatomy stays intact
- When roots are put into the water, they continue to draw up water for days
46
anatomy of the stem
-epidermis: cover and protect
-Ground tissue: support
-Vascular Tissue:
*diff arrangements of vascular tissue in diff lineages but always together
-Holds xylem and phloem
47
xylem
transport water and minerals
dead at maturity
energy comes from the sun
the source of energy that drives bulk flow comes from leaves
pressure= drinking straw
hollow inside
tracheids, vessel elements
48
phloem
transport sugar, proteins, hormones
pressure is like a garden hose
sieve tube elements
companion cells
49
Cohesion and tension
Water is polar
50
Cohesion Tension Theory
1. Water evaporates from inside the mesophyll and creates pull from surface tension
2. Cohesion pulls water up xylem in stem
3. Negative water potential (osmotic pressure and pulling of water) draws water in from roots
51
Where is the pressure the lowest
in the atmosphere
52
Where is the pressure highest
roots
53
what is the driving force for moving water
transpiration of water aka evaporation from the leaves
54
what connects the water molecules to each other
hydrogen bonding aka cohesion
55
Reduced transport of water in plants
- Fewer stomata open in leaf
- Cool, humid weather
- High salt in soil creates low osmotic pressure in soil
56
Increase transport of water in plants
- More stomata open in leaf
- Hot, dry weather
57
cavitation
Too much negative pressure
-air comes out of solution
-also happens in freezing weather
Solutions:
-small diameter pipes
-small pores at the end of tracheids
58
Lignin
provides support for the cell walls in xylem and gives plants woody structures
59
sources
- where sucrose is put into transport
- made by photosynthesis (leaves)
- taken out of storage (starch to sucrose)
60
sinks
- where sucrose is taken out of transport
- used by mitochondria to make ATP
- put into storage (starch or storage vacuoles)
- converted into plant structure
61
examples of sources
leaves doing photosynthesis and storage roots during the early spring when they release food for growing leaves
62
examples of sinks
growing roots and flowers (they use more energy than they produce)
63
translocation
-Movement of sucrose from one location to another through phloem
-From source to sink
*Phloem loading
*Phloem unloading
-Explanation: pressure-flow hypothesis
64
phloem loading
- leaf cells produce lots of sucrose
*excess flows into phloem
*diffusion through plasmodesmata
- sucrose can also be actively transported into phloem by proton pumps and H+/sucrose symporters
65
Phloem unloading
-facilitated diffusion to growing cells (convert sucrose to structure of energy)
-active transport to storage (move against concentration gradient)
66
functions of roots
absorb nutrients and water, anchor plant in soil, storage of macromolecules
67
rhizosphere
bacteria and fungi within soil around the root
- Plants secrete signals to promote growth of microorganisms around root
68
mycorrhizae
partially inside the root
FUNGI
GREATLY INCREASES SA
MOST PLANTS DO THIS
-plants and fungi team up: the plants do photosynthesis and provide sugars to fungi; the fungi absorb nutrients from soil and give some soil
-symbiosis: plants provide sugars to mycorrhizae
-loss of mycorrhizae reduces nutrient uptake by plants
- hyphae spread out in plant and absorb nutrients
69
exterior anatomy of the roots
Absorption of nutrients
*Root Hairs:
-cover surface of roots
-small projections of cells
-greatly increase surface area
*Epidermis
-protective skin
-no cuticle
-form root hairs
70
interior anatomy of the roots
Vascular Tissue (majority of the space)
-Xylem (water and minerals)
-Phloem (tissue for hormones, sugars, etc.)
Endodermis (wall around X&P)
-inner protection around vascular tissue
-keeps bad stuff out
-creates casparian strip: an impermeable barrier between cells
Pericycle: stem cells that can produce lateral roots
-just inside the endodermis
71
macronutrients
-used in high concentrations in plants
*lower concentrations in soil
-nitrogen, phosphorus, potassium
72
micronutrients
-used in lower concentrations in plants
*boron, chlorine, iron, copper, zinc
73
limiting factor
whats limiting heavy growth
74
rhizobia
bacteria that live in the roots
FIX NITROGEN
forms nodules
few plants do this
legumes
symbiosis
75
nutrient import
active process rather than absorption
76
symplastic route to the xylem
cuts through the cell
77
apoplastic route to the xylem
cuts through the cell walls and cant get through the endodermis without entering the cell (this prevents toxins from entering)
77
apoplastic route to the xylem
cuts through the cell walls and cant get through the endodermis without entering the cell (this prevents toxins from entering)
78
pollen
sperm producing gametophyte
*multicellular haploid structure that produces sperm
*can travel in dry air
*doesnt need flagella to swim in water
-pollen does not make sperm it just contains them
79
ovule
egg producing gametophyte
*multicellular haploid structure that makes eggs then becomes nutrient source for embryo
*larger than pollen and fixes to plant inside modified leaves (cone or flower)
80
spores
seedless plants with single-cell reproduction
81
microspore
pollen/male part
82
megaspore
ovule/female part
83
seeds
post-fertilization embryo
embryo packed in casing with food
84
common features of seed plants
*sporophyte dominant
*gametophyte is tiny and dependent
*seeds
*dry fertilization
85
gymnosperms
seed plant
cones are main reproductive structures
naked seeds
86
angiosperms
seed plant
flowers
seeds in fruit
*pollen producing structures (anther)
*ovaries enclosing the ovule
*ovaries mature into fruit
87
botanical fruit
culinary fruit
*sweet, juicy part of plant
culinary vegetable
*savory parts of plant
botanical fruit
*swollen ovary surrounding seeds
88
Which part of photosynthesis directly used ATP
rearranging molecules to form RuBP
89
the transfer of sunlight energy to electrons is accomplished by
chlorophyll
90
sucrose loading
generate the pushing force that creates the flow through sieve elements in the phloem
91
the tension in cohesion-tension theory refers to
the pulling force creates at the surface of a film of water
92
water exits the leaf through
transpiration
93
transpiration pulls water up through the xylem by
cohesion
94
sugar leaves the phloem by
diffusion
95
how do proton pumps impact potassium uptake
they decrease the positive charge within the cell to attract potassium ions
96
what do ferns require for fertilization
water
97
sweet fruits with many seeds help by
spreading seeds over a long distance
98
all seed plants also have
xylem and phloem
99
what anatomy do angiosperms have that gymnosperms do not
ovaries
100
gametes (n) go through fertilization and produce
a zygote (2n)
101
zygote (2n) goes through mitosis and produces
a sporophyte (2n, multicellular, diploid)
102
a sporophyte goes through meiosis and produces
spores (n)
103
spores go through mitosis and produce
gametophyte (n, multicellular, haploid)
104
gametophytes (n, multicellular, haploid) go through mitosis and produce
gametes (n)
