Unit 4 Flashcards
a.(Leaf diagram functions) Epidermis layer
It protects against water loss, regulates gas exchange, secretes metabolic compounds, and (especially in roots) absorbs water and mineral nutrients.
b.(Leaf diagram functions) Mesophyll layers
is a leaf’s core underlying material. It is found in the middle of the leaf, between two layers of epidermal cells. It aids in gas exchange and photosynthesis via chloroplasts.
c.(Leaf diagram functions) Guard cells
The two cells that flank the stomatal pore and regulate the opening and closing of the pore.
d.(Leaf diagram functions) Stomata
Regulate gas exchange between the plant and environment and control of water loss by changing the size of the stomatal pore.
e.(Leaf diagram functions) Vascular bundles
plant stem structure that contains xylem and phloem tissue
(Leaf diagram functions) xylem
transports water and minerals to the leaves
(Leaf diagram functions) phloem
transport the photosynthetic products to the other parts of the plant.
a.(Chloroplasts functions) Stroma
The fluid of the chloroplast surrounding the thylakoid membrane; involved in the synthesis of organic molecules from carbon dioxide and water.
b.(Chloroplasts functions) Thylakoids
A flattened membrane sac inside the chloroplast, used to convert light energy to chemical energy.
c.(Chloroplasts functions) Grana
The stacks of thylakoids embedded in a chloroplast.
d.(Chloroplasts functions) Lamellae
Increase the efficiency of photosynthesis by keeping grana at a distance so that they do not clutter together.
e.(Chloroplasts functions) Thylakoid membrane
The photosynthetic membrane within a chloroplast that contains light gathering pigment molecules and electron transport chains.
f.(Chloroplasts functions) Thylakoid lumen
A fluid-filled interior space enclosed by the thylakoid membrane.
Photoexcitation
absorbtion of a photon by an electron of chlorophyll. The photon strikes the chlorophyll molecule and its electron gains energy and moves from its ground state to its excited state.
Photosystems
Cluster of photosynthetic pigments and proteins embedded in the thylakoid membrane.
Photons
A quantum, or discrete quantity, of light energy that behaves as if it were a particle.
Electromagnetic Radiation
A form of energy exhibiting wavelike behaviour
Spectroscope
An instrument that separates light into a spectrum.
Electromagnetic spectrum
the range of wavelengths or frequencies over which electromagnetic radiation extends.
Van Helmont
Plants grow by taking in water
Joseph Priestley
Discovered oxygen gas
Action spectrum
A graph that profiles the relative effectiveness of different wavelengths of radiation in driving a particular process.
Van Niel
Photosynthetic transfer of electrons, from a donor to an acceptor
Blackman
Light and Dark reactions, dépendant on CO2 availability
Engelmann
Discovered how different wavelengths of light affect the rate of photosynthesis
Ground State
Lowest Energy state of an electron
Excitation
An electron being promoted from a lower to a higher energy level
Reaction centre
Large protein complex containing chlorophyll a
Photosystem 1
Captures light energy, converts to chemical energy, used to produce ATP + NADPH
CYCLIC
Absorption spectrum
The range of a pigment’s ability to absorb various wavelengths of light
Photosystem 2
Captures light… etc, produces ATP and O^2
Non-cyclic
PS2 produces O2
Accessory pigments
a.B-carotene
b.xanthophylls
c.anthocyanins
Z-Protein
Protein produced by Ebola virus disease, or the way electron transfer chains are shaped “z-scheme”
Photosynthetically active radiation
Light btwn the frequencies of 400-700nm is useable b photosynthetic organisms
important for plant
determines energy available for photosynthesis
Phosphorylation
The production of ATP by chemiosmosis during the light reactions of photosynthesis
Ground state
The lowest energy state of an atom
Cyclic electron flow
Occurs in PS1
Transfer in closed loop
Only produces ATP
Balances rate of ATP+NADPH
Antenna complex
number of chlorophyll and accessory pigments that absorb photons and transfer energy from pigment to pigment until they reach the reaction centre
Reaction centre
protein complex containing chloryphyll a that absorbs the energy, passes the electron to an acceptor and becomes reduced.
Non-cyclic electron flow
Occurs in both photosystems
Linear transfer
Produces ATP AND NADPH
Generates O2
Known as Z scheme
Photophosphorylation
The production of ATP by chemiosmosis during the light reactions of photosyntesis
C 4 photosynthesis
modification for dry environments. C-4 plants exhibit modified anatomy and biochemical pathways, which enable them to minimize excessive water loss and maximize sugar production.
CAM plants
plants close their stomata during the day, collect CO2 at night, and store the CO2 in the form of acids until it is needed during the day for photosynthesis.
Transpiration
loss of water vapour from plants through the stomata
Light reactions
first set of reaction of photosynthesis in which light energy exites electrons in chlorophyll molecules, powers chemiosmotic ATP synthesis, and results in the reduction of NADP+ tp NADPH
Carbon fixation
The process of incorporating CO2 into carbohydrate molecules
Calvin cycle
light-independent reactions of photosynthesis in which energy from ATP and NADPH is used to build high-energy compounds such as sugar.
Factors affecting photosynthesis
a. Light intensity-light-compensation point, light-saturation point
b. Temperature
c. Oxygen concentration
d. Carbon dioxide concentration
e. Quality of light
