Cellular respiration Flashcards
what do animals and plants use products of photosynthesis for
metabolic fuel. product of photosynthesis is glucose
when we take in glucose, proteins, fats, and other carbs, how do they come into our body
they do not come to us the way out cells can use them
where does breakdown of glucose begin
in the cytoplasm– the liquid matric of the cell
aftfer breakdown of glucose, life diverges into what two forms and pathways
- anaerobic respiration (fermentation)
- aerobic respiration
a series of ____ breaks down ______ to release ____
- chemical reactions
- glucose
- energy
after glucose is broken down to release energy, where is the energy stored
in ATP
cr takes place in what kind of cells
all eukaryotic cells
cr formula
c6h12o6 + o2 = co2 + h2o + ATP
how is cr similar to combustion reaction
same format
how is cr differnt from combustion reaction (3)
- is a slower reaction
- energy is released in steps (otherwise spontaneous combustion would be the result)
- energy released is stored in atp
cristae vs inner membrane
cristae is the inner foldings the inner membrane makes
intermembrane space
space between inner membrane and outer membrane
small space to quickly accumulate protons
inner membrane
membrane of the matrix
contains etc and atp synthase for oxidative phosphorylation
cristae (2)
inner foldings made by inner membrane
highly folded as to increase sa:vol ratio as to increase atp production
- where atp is made
outer membrane
outer membrane of the entire mitochondria
contains transport proteins for shuttling (taking in) pyruvate into mitochondria
matrix (2)
space within the inner membrane
- has appropriate enzymes and suitable pH for krebs cycle
- where 3 carbon pieces (that came from carbohydrates (glucose)) are broken down into co2 and h2o (etc and krebs)
most of the energy from cell respiration is converted into what
atp
how does the atp substance help cell activities
powers most cell activities
which phosphate group has a high cemical bond in ATP
the last one
uses of atp *(5)
- basically everything
- for active transport to move substances across cell membrane
- phagocytosis
- muscle contractions
- heat production
transformation of chemical energy in food into chemical energy cells can use:
atp
what four stages does cr take place in and where do they take place
- glycolysis - cytoplasm
- pyruvate oxidization - in cytoplasm/mitochondria
- kreb’s cycle- matrix
- etc and chemiosmosis - inner membrane
what purpose does krebs serve for etx
makes molecules needed for etc
what are the electron carriers of cr
nadh and fadh2
nadh only for glucolysis to etc, both for krebs to etc
which two stages of cr release co2
krebs and pyruvate oxidization
does glycolysis perform only for aerobic resp or anaerobic resp
both
stages of glycolysis (5)
- glucose enters from outside the cell completely
- 2 adp + 2p turn into 2 atp
- series of reactions which break 6 carbon glucose molecule into two 3 carbon molecules called pyruvate (aka pyruvic acid)
- yields 2 atp for every pyuvic acid (4 atp total) (2adp + 2p = 2atp)
- yields 2 nadh per GLUCOSE molecule (1 nadh per pyruvic acid) (nad+ + 2 electrons = 2 nadh (+ H+???)
glycolysis (2)
- occurs in cytoplasm
- process is an all-organism process. from bacteria to humans, they all perform the SAME way
what happens to the products of glycolysis (3)
- pyruvate enters the next stage (pyruvate oxidization)
- nadh is used in chemiosmosis and etc (carries electrons)
- atp is used by cells
pyruvate oxidizaion (3)
- requires o2
- takes place in mitochondria
- modifies pyruvate before krebs cycle
pyruvate oxidization steps
- carbon molecule is removed from pyruvate (3carbon molecule turned into 2 carbon). carbon molecule exits as co2
- when carbon is removed, pyruvate becomes acetyl
- nad+ is reduced to nadh (+H+)
- acetyl joins to a carrier called coenzyme A to form acetyl CoA
krebs cycle
- in matrix
- completes the breakdown of glucose
krebs cycle steps (6 (+3 small)
- 2 carbons enter as acetyl coa
- coa part removed
- carbon leaved as co2
- 3 molecules of nad are REDUCED to form NADH (+ 3H+)
- one fad is reduced to form fadh2
- hydrogens and electrons are stripped from acetyl coa and are loaded onto nad and fad to form nadh and fadh2 - one adp + p is formed into atp
- for each glucose (2 pyruvates), one atp is formed, so 2 atp is formed per pyruvate.
- loads up coenzymes (nadh and fadh2) with H+ and electrons to move onto etc and chemiosmosis`
how many pyruvates is used per turn of krebs cycle
1 (1 atp produced)
what product of the krebs cycle provides energy for cell processes
atp (1)
what product of the krebs cycle provides REDUCING energy for cell processes
(3) nadh and (1) fadh2
what does the inner membrane contain that carries electrons
proteins
ETC STEPS (6 (+0.5 x2?)
- enter nadh and fadh2
- takes 2 electrons from the both of them that were produced in glycolysis and krebs cycle
- nad+ and fad are recycled and can be used in krebs and glycolysis
- as the electrons move from protein to protein, a small amount of energy is released. this energy is used to move H+ (protons) into the intermembrane space. energy released called
- oxygen is the final electron acceptor, in which is it reduced to form water (2H+ + 1/2 O2 + 2 e-)
- chemiosmosis occurs, in which protons flow through the atp synthase from the intermembrane space TO the matrix.
- as hydrogen flow down their concentration gradient this way, space energy is released
- this energy is used to make atp
total atp produced + atp produced from every step
glycolysis - 2
krebs - 2
etc and chemi. - 32/34
total: 36
what happens to etc if there is no o2
lack of o2 causes system to back up all the way to glycolysis because the nadh and fadh2 cannot be recycled and continue the cr process.
hence why if there is no o2, no atp = cells die = you die
chemiosmosis
H+ flows through the atp synthase from the intermembrane space to the matrix, creating atp in the process.
- makes the most atp for cr
chemiosmosis requires (2)
- a concentration gradient of H+ ions
- an atp synthase channel, which is found in the inner membrane
what is the atp synthase ONLY PLACE permeable to
H+ protons
where is the proton concentration hgihest
intermembrane space
where does electron transport cause H+ to build up (+1)
in the intermembrane space
- H+ protons are NOT allowed to diffuse back into the matrix
nadh carries electrons gained from food (glucose) to the ____
etc
what is the byproduct of the etc
h2o (when o2 accepts electrons)
per GLUCOSE (2 pyruvates), how much nadh and fadh2 is produced from each step
glycolysis- 2 n
pyruvate oxidization- 2 n
krebs- 6 n and 2 fadh2
anaerobic organisms are important for what
they can’t be too energetic but are important for global recycling of carbon
aerobic vs anaerobic resp (5)
aerobic
1. requires o2
2. complete oxidization of respiratory materials
3. produces max 38 atp molecules per glucose
4. steps consist of glycolysis, krebs cycle, and oxidative phosphorylation
5. water is formed
anaerobic
1. doesn’t require energy or o2
2. incomplete oxidization of respiratory materials
3. produce only 2 atp per glucose
4. consists of glycolysis and incomplete breakdown of pyuvate
5. h2o is normally not formed
can some organisms thrive environments with little to no o2? give examples
yes
ex: marshes, bogs, gut of animals, sewage treatment ponds
what is an organism called if it does not use o2
‘an’ anaerobic
what do the final steps of anaerobic resp serve and result in?
results in no more atp, only the 2 made.
final steps in these pathways serve ONLY to regenerate NAD+ from NADH so it can return to pick up more electrons and hydrogens in glycolysis and restart the process of glycolysis
what are the end products of anaerobic resp
ethanol and co2 (single cell fungi (yeast) in beer/bread)
- only occurs in plant cells
lactic acid (muscles)
- only in animal cells
fermentation
when o2 is not present, fermentation is after glycolysis, regenerating nad+ from nadh needed for glycolysis to continue
draw out:
- entire cr steps (glycolysis, pyruvate oxidization, krebs cycle, etc and chemiosmosis/oxidative phosphorylation
- mitochondria labelled diagram ++ functions
- entire cr if anaerobic (glycolysis, fermentation)
do it
what is etc and chemiosmosis also referred to as
oxidative phosphorylation
lactic acid fermentation
pyruvate is converted to lactate
in the absence of o2, what does the nadh do with its h+
nadh generated from glycolysis passes its h+ atoms to either acetaldehyde (there is 2, as acetaldehyde is formed from acetyl/pyruvatae) to produce latic acid
(lactic acid fermentation)
what is nad+ done with in absence of o2
nad+ from nadh is recycled to continue the process of glycolysis
what do muscles do with pyruvate if there is absence of o2
converts it to lactic acid
when o2 is reintroduced, lactate can be converted back into pyruvate
products of fermentation (6)
- wine
- soy sauce
- beer
- bread
- carbonated beverages
- cheese
LACTIC acid causes… (4)
what are they signs of
- muscle soreness
- fatigue
- muscle cramps
- stiffness
all signs of oxygen debt in muscles
anaerobic resp in animal cells. why is it important (4)
- produces lactic acid
- when cells arent recieving enough o2, muscles become cramped due to a buildup of lactate
- when o2 becomes available, lactate is converted back to pyruvate, which is then continued onto the krebs cycle
- important because it provides short burst of energy when o2 is not available. however, it can only produce a small amount of atp compared w aerobic resp (2atp)
ethanol fermentation (3)
- only in plant/yeast cells
- pyruvate is converted into ethanol using one nadh molecule, which is then recycles back into glycolysis
- used for fuel (ethanol from corn or wheat fermentation)
how is pyruvate converted into ethanol
using one nadh molecule. nad+ is recycled to glycolysis
anaerobic resp in yeast cells (3)
- anaerobic resp produces ethanol, which is called fermentation
- pyruvate is converted to ethanol using one nadh molecule, which is recycled back into glycolysis
- fermentation has commercial uses: breweries, bread making, wine making
during fermentation, nad+ is what? why?
nad+ is RESTORED. this gives cells the opportunity to continue with cr if o2 becomes available
what is so different about the process of alcohol fermentation from lactic acid fermentation
alcohol:
glucose > 2 pyruvate > 2 acetaldehyde > 2 ethanol
lactate:
glucose > 2 pyruvate > 2 lactate
what are plants, animals, and yeast’s use of fermentation
plants- ethanol is produced from ALCOHOL fermentation of the glucose from corn or other plants
animals- form of fermentation takes place in bacteria and in the muscle cells of animals
yeast- production of ethanol and co2
cr and photosynthesis comparison
photosynthesis
- takes place in chloroplast of cells, this process is what gives energy to all organisms either indirectly or directly
cr
- in the cytoplasm and mitochondria of the cells, this process is by which living things convert o2 and glucose to h2o and co2, therefore yielding energy
energy sources and energy result: photosynthesis vs cr
source
photo: light
cr: chemical bonds
result
photo: energy stored
cr: energy released
