Unit 8 Flashcards
photosynthesis
method of converting solar energy into chemical energy stored in the bonds of complex food molecules usable by cells
what does photosynthesis convert
solar energy into the chemical energy of a carbohydrate
what are the three things photosynthysis is a source of
food, oxygen, chemical energy
phototroughs
use sun energy to make organic compounds (like glucose) from light
chemoautotrouphs
use chemical energy to make organic compounds
what are chloroplasts
carbohydrate factories that use solar energy to form glucose, which is either used by the organism immediately or converted into other forms such as starch, cellulose, lactose, or sucrose
electromagnetic spectrum
a continuum of all electromagnetic waves (energy) arranged according to frequency and wave length
what is a pigment
a chemical that absorbs light energy and gives an object its color
what does chlorophyll not absorb and what does it cause
it doesn’t absorb green light, making it reflect the color green
what is light necessary for
the production of chloroplasts as well as the melanin
what is melanin
a protein pigment found in epidermal cells, protects skin against radiation from the sun. and it is the reason you tan when you lay out in the sun.
what are the 4 types of chlorophyll
Chlorophyll A, B, C, D
what is Chlorophyll A
most abundant and most important photosynthesis; blueish green pigment
what is Chlorophyll B
yellowish-green
what is Chlorophyll C
in brown algae
what is Chlorophyll D
red algae
where does most photosynthesis occur
in leaves
what is leaf structure closely related with
its function
in a leaf where does CO2 have to go
chloroplasts
in a leaf where does O2 have to go
out of the leaf (waste product)
what is stroma
colorless fluid surrounding the grana within the chloroplast
what are the “chocolate chips” in chloroplasts
chlorophyll
what is the “syrup” in a chloroplast
stroma
what is the “sausage” in the chloroplast
lamella
what are the “pancakes” in chloroplasts
thylakoids
what are the “stacks of pancakes” in the chloroplasts called
grana
outer membrane
separates the chloroplasts from the rest of the cell
inner membrane
regulates the diffusion of necessary materials in and out of the chloroplast
what does the inner membrane increase
the amount of surface are for more photosynthesis
what does the stroma serve as
channels in the epidermis
what does stroma allow gases to do
diffuse directly into and out of the leaf
where are the stromata mostly located
the bottom of the leaf
why are the stromata mostly located on the bottom of the leaf
to reduce water loss (transpiration) caused by direct exposure to the rays of the sun
what colors are carotene and xanthophyll
orange and yellow
what happens to the chlorophyll when the light intensity increases
it begins to break down, allowing other pigments to show through
why do most plants appear green
because the chlorophyll masks all of the other pigments since it has such a high concentration in the leaf
what is the #1 energy-carrying molecule in all living things
ATP
where is energy stored
in the phosphate bond
what does photosynthesis produce
thousand of new glucose molecules each second
what two stages can photosynthesis be broken down into
the light reaction and the dark reaction
what does the light reaction require
light, it doesn’t occur unless light is present
where does the light reaction take place
the grana
what does the light reaction require other than light
chlorophyll
what are the two steps of the light reaction
photophosphorylation and electron transport chain
what is photophosphorylation also known as
photosystem
what happens during photophosphorylation
chlorophyll captures light energy to produce energized electrons
what is a waste product of photophosphorylation
O2
does the dark reaction require light
no, it can occur at any given time
where does the dark reaction take place
the stroma
what does the dark reaction require
the products of the light reaction
what happens during carbon fixation
ATP and NADPH from the previous step difuse into the molecule; these halves then come together to form a glucose molecule
what does carbon fixation turn “useless” inorganic carbon into
“useful” organic glucose
what can the glucose produced by photosynthesis be stored as
starch and cellulose
what are starch and cellulose
carbohydrates
what are 3 factors that can affect photosynthesis
light intensity, CO2 concentration, temperature
light intensity
the stronger the light intensity, the faster the rate of photosynthesis until a maximum is reached as all reactants and all organelles are used
CO2 concentration
the greater the concentration of CO2, the faster the rate of photosynthesis until a maximum is reached
temperature
the rate will be slower in very cold and very hot temperatures. An optimum temperature with a maximum rate will be achieved
adaptations
special features that allow a plant or animal to live in a particular place of habitat
why are certain plants found in some places but not others
their adaptations help them survive in certain environments and not others
what are most plants in our area
C3
what do C3 plants go through
the Calvin cycle