Photosynthesis and Cellular Respiration Flashcards
photosynthesis
conerts light energy from the sun into chemical energy used by living cells
plants and some bacteria do it
all need chlorophyll (green pigment)
formula
the leaf
most photosynthesis takes place in the palisade layer of the leaf
chloroplasts
orgenelles in the plant cells, have an outer and inner membrane
stroma
inside fluid chloroplast
thylakoids
within stroma are membrane, stacked into grana
lumen
inside the thylakoid is a watery space called the lumen
chlorophyll
green pigment in thylakoid membrane
chlorophyll a- primary pigment
chlorophyll b- carotene, xanthophyll, become visible in fall
pigments
each pigment absorbs different wavelengths
green light is reflected, red and blue are absorbed
light dependent reactions
- water splits (photolysis) and releases an electron, protons (h) and o2 is produced
- photon of light causes an electron to move from photosystem 2 to the ETC
- electron travels through ETC, pumping protons into lumen as it goes
- electron reaches photosystem 1 and stops, must gain energy from another photon to continue
- the electron is transfered to NADP- a coenzyme that becomes reduced to NADPH
- protons building up in the lumen form agradient and diffuse out of the lumen through ATP synthase into the stroma
this process releases energy which is used by ATP synthase to produce ATP from ADP and p
noncyclic photophosphorlation
electron flow is one way
cyclic photophosphorlation
photosystem 1 acts on it’s own- electron goes from PS1 to ETC and back to PS1, pumps one proton in the process
produces ATP when NADP is scarce
light independent reactions/calvin benson cycle
light is not required
occurs in the stroma of chloroplasts
converts CO2 to glucose
requires ATP for energy and NADPH for hydrogen source- these come from light reactions
light independent steps
co2 attatches to a 5 carbon sugar called RuBP
the resulting 6 carbon sugar is split into two 3 carbon PGA molecules
energy from ATP is used to release h from NADPH
the h attatches to PGA to form PGAL
PGAL produces: glucose, startch etc. and replenishes RuBP
this cycle runs 6 times to produce one glucose molecule
cellular respiration
chemical reactions used by all cells to brekdown glucose into energy rich ATP molecule- formula
exothermic reaction- releases energy
glycolosis
occurs in the cytoplasm of the cells
does not need oxygen, uses 2 ATP to start
glucose is broken down to 2 pyruvate and a net of 2 ATP and 2 NADPH are made
anaerobic respiration
occurs in the cytoplasm
in absence of oxygen
NADH generated from glycolosis passes it’s h atoms to either acetaldehyde to produce ethanol in a yeast or to pyruvate to produce lactic acid if you are us
products of alcoholic fermentation
wine, beer, soy sauce, bread, carbonated drinks, cheese
lactic acid production causes
muscle cramps, soreness, stiffness, and fatigue. lactic acid is then taken to the liver by bloodstream and converted back into glucose
aerobic respiration
requires oxygen
occurs in the mitochondria
consists of the transition/link reaction, kreb’s cycle and electron transport system
the link reaction
co2 is removed from pyruvate
NAD is reduced to NADH
co-enzyme A is attatched to the remaining 2 carbon molecule to form acetyl Co-A
makes 1 NADH and 1 Co2
kreb’s cycle
occurs in the matrix of the mitochondria
the acetyl Co-A combines with a 4 carbon acid to produce a citric acid
makes 3 NADH, 1 FADH, 2 Co2 and 1 ATP
the electron transport system
occurs in the cristae of the mitochondria
NADH drops of hydrogen at the first coenzyme
FADH drops of hydrogen at the second coenzyme so it generates less ATP
electrons are transported through proteins
at the end of the chain, electrons combine with oxygen and water is formed
this electron movement pumps protons into the outer compartment of the mitochondria
and generate less ATP as they travel through ATP synthase- called oxidative phosphorlation- each NADH produces 3 ATP, each FADH produces 2 ATP
