photosynthesis Flashcards
what does oxidation mean?
loss of electrons or hydrogen from a substance.
what is reduction?
gaining of electrons or hydrogen by a substance.
oxidation or reduction in photosynthesis?
in photosynthesis, carbon dioxide gains electrons to form glucose so it is reduced.
oxidation or reduction in cellular respiration?
in cellular respiration, glucose is broken down, it loses electrons and becomes oxidized.
autotrophs vs heterotrophs?
autotrophs are producers: they produce their own food from inorganic substances.
heterotrophs are consumers: they cannot produce their own food and rely on consuming organic compounds made by other organisms.
what organisms can perform photosynthesis?
plants, algae, cyanobacteria, some protists, and some photosynthetic bacteria can use sunlight, co2, and water to produce glucose and oxygen through the process of photosynthesis.
where does photosynthesis take place?
takes place in the chloroplasts
what is the structure of the chloroplast?
outer membrane, inner membrane, intermembrane space, stroma, thylakoids, granum,
do unicellular protists contain chloroplasts?
yes many unicellular protists contain chloroplasts and are capable of photosynthesis
do cyanobacteria and some photosynthetic bacteria have chloroplasts?
no they do not contain chloroplasts, they have thylakoid membranes and chlorophyll.
where are most of the chloroplasts found in plants?
most chloroplasts are found in leaves : 30-50 chloroplasts per plant cell.
what is the internal structure of a leaf?
there is the epidermis which is the outer layer that protects the leaf: covered by a waxy cuticle to reduce water loss.
the middle layer is the mesophyll: densely packed with chloroplasts and the air spaces facilitate the exchange of co2 and o2 necessary for photosythesis.
there are vascular bundle: xylem and phloem
and stomata: small openings in the epidermis that allow for gas exchange.
then there is the lower epidermis.
chloroplasts are found primarily in?
the cells of the mesophyll tissue.
how does co2 and h2o reach the structures?
co2 enters the leaf through small openings called stomata and eventually moves through the intercellular spaces of the mesophyll.
h2o: water is absorbed form the soil by the roots and travels up through the vascular bundle and eventually reach the mesophyll cells where photosynthesis occurs.
photosynthesis is a two stage process?
- light dependent reactions and light independent reactions: calvin cycle
light dependent reactions, role of light?
photosynthesis uses sunlight as its primary energy source. the visible light portion of the electromagnetic spectrum includes wavelengths that our eyes can see such as red, blue, green etc.
photosynthesis is driven by?
the visible light portion of the electromagnetic spectrum.
the visible light(wavelengths we can see) is absorbed by?
pigments found in chloroplasts: chlorophyll a, chlorophyll b, and carotenoids
different pigments absorb?
light of different wavelengths
where are the pigments located?
in the thylakoid membrane
why are leaves green?
the major pigment is chlorophyll a
what is not absorbed by chlorophyll?
the green wavelength. chlorophyll gives plants their green color because it does not absorb the green wavelengths and it is reflected.
what is absorbed by chlorophyll
absorbs in violent-blue and red light of the spectrum
which wavelength of light can drive photosynthesis?
the wavelengths of visible light that effectively drive photosynthesis are blue light and red light.
