Respiration Flashcards
what is respiration?
the release of energy by breaking down food
what food is mainly broken down by respiration?
glucose
how is respiration carried out?
in a series of enzyme controlled reactions
2 ways that the energy from respiration may be used
some used to make ATP
some given off as heat energy
what is atp known as
energy currency
what is the immediate source of energy for all cells
atp
ATP
adenosine triphosphate
3 components of atp molecules
adenine
ribose
3 phosphate groups
where does atp store anergy
in the phosphate bonds (~P)
what happens to atp during the breakdown
the last phosphate is broken off and adp is formed
ADP
adenosine diphosphate
ATP ->
ATP + P + Energy Released
4 things done by the release of energy from ATP
muscle contraction
nerve impulse transmission
synthesis of molecules
cell division
How is ATP formed?
from the combining of ADP and a phosphate. Energy is needed
Is energy needed to form ATP?
yes
Phosphorylation
adding of a phosphate
where is ATP found?
in small quantities in all living cells
when is ATP produced?
it is continuously produced wherever it is needed
speed of the breakdown of atp
it can be broken down and remade very quickly
What is the name for the formation and breakdown of ATP?
the atp cycle
are digestion and respiration separate?
they are 2 separate things but one is reliant on the other
Aerobic respiration
the release of energy that requires oxygen
are most organisms aerobic or anaerobic
aerobic
What happens to the substrate in Aerobic respiration ?
it is completely broken down and a large amount of energy is released
net yield per glucose molecule of ATP in aerobic respiration
38 ATP
equation for aerobic respiration
C6H12O6 + 6O2 -> 6CO2 + 6H2O + Energy
anaerobic respiration
the release of energy that does not require O2
what happens to the substrate in anaerobic respiration ?
it is partially broken down and a small amount of energy is released
Net energy yield of atp per molecule of glucose in anaerobic respiration
2
other name for anaerobic respiration
fermentation
2 types of anaerobic respiration
alcohol fermentation
lactic acid fermentation
where does alcohol fermentation occur?
in yeast
equation for alcohol fermentation in yeast
glucose -> 2 ethyl alcohol + 2CO2 + Energy
where does lactic acid fermentation occur?
in human muscle cells and in some bacteria
equation for lactic acid fermentation
glucose -> 2 Lactic acid + energy
how many stages in aerobic respiration
2
name the 2 stages of aerobic respiration of glucose
glycolysis
kreb’s cycle
does glycolysis require O2?
no
where does glycolysis occur?
in the cytoplasm
does kreb’s cycle require O2
yes
where does the kreb’s cycle occur
in the matrix of the mitochondria
what is the final step in the respiration of glucose?
the electron transport chain
where does the electron transport chain occur?
on the inner membrane of the mitochondria
3 steps of glycolysis
glucose broken down to form 2 pyruvic acids
small amount of energy released
ATP is made using the energy released
how many carbons in glucose
6
how many carbons in pyruvic acid
3
energy released from kreb’s cycle
a large amount of energy
what condition is necessary for the pyruvic acid to go to the mitochondrion and be completely broken down?
the presence of oxygen
if O2 is present an the pyruvic acid is completely broken down, what is it converted into
Acetyl co-enzyme A
how many carbons in Acetyl co-enzyme A
2
what happens to Acetyl co-enzyme A
it goes into the Krebs cycle
what happens to Acetyl co-enzyme A when it is in the Krebs cycle
it is gradually broken down in a series of enzyme-controlled reactions
4 things that are made in the krebs cycle from the breakdown of Acetyl co-enzyme A
CO2 is released
ATP is made
Electrons and H+ ions are released
NADH is made
function of NAD+
picks up and carries electrons and hydrogen ions in the cell making NADH
equation for formation of NADH
NAD+ +2e- + H+ -> NADH
what later happens to the NADH
it releases the high-energy electrons on to the elctron transport system and energy is released from them to make atp
how many atp per krebs cycle
1
how many atps per pyrivic acid
1
how much ATP is made directly during glycolysis and krebs cycle
very little ATP
total yield of atp per gluocose molecule in glycolysis and krebs cycle
4
where is most of the energy from food got
in the form of high-energy electrons carried by NADH
explain the electron transport chain
a lot of energy is released and used to make ATP when high energy electrons are released from NADH and passed along the electron transport chain to oxygen
where does electron transport chain occur
on the inner membrane of the mitochondria (cristae)
what happens to the elctrons when they are released from NADH in the electron transport chain
they are passed from molecule to molecule
what occurs with every electron transfer in the electron transport chain
energy is released
describe the electrons at the end of the electron transport chain
they are now low in energy
what happens to the low energy electrons at the end of the electron transport chain
they combine with oxygen and H+ ions to form H2O
what is the energy from the electron transport chain used to do
making ATP
NAD+
nicotinamide adenine dinucleotide
when NADH passed its 2 high energy electrons along the electron transport chain, enough energy is made to make how many atp?
3
what happens to NAD+ at the end of the electron transport chain
it is reused
when does anaerobic respiration occur?
if O2 is absent from the cell
what happens to pyruvic acid during anaerobic respiration
it stays in the cytoplasm and is converted to ethanol and CO2 or lactic acid
net gain per molecule of glucose in ATP
2 ATP
when may muscle cells undergo anaerobic respiration
during periods of vigorous exercise
2 function of anaerobic respiration
in bacteria to turn milk to yogurt, cheese, sour milk
another bacteria turn fresh grass to silage
TO PREPARE AND SHOW THE PRODUCTION OF ALCOHOL BY YEAST
what do you put in each of the conical flasks?
an equal volume of glucose
TO PREPARE AND SHOW THE PRODUCTION OF ALCOHOL BY YEAST
what is put in one conical flask
yeast
leave it out of the control
TO PREPARE AND SHOW THE PRODUCTION OF ALCOHOL BY YEAST
what do you attach to each flask?
a fermentation lock half filled with water
TO PREPARE AND SHOW THE PRODUCTION OF ALCOHOL BY YEAST
what is the function of the fermentation lock?
it prevents entry of air but allows the escape of CO2
TO PREPARE AND SHOW THE PRODUCTION OF ALCOHOL BY YEAST
where an how long do you leave the flasks
in a water bath at 20-35ºC overnight
TO PREPARE AND SHOW THE PRODUCTION OF ALCOHOL BY YEAST
how do you know when fermentation is over?
when no more CO2 bubbles are released
TO SHOW THE PRODUCTION OF ALCOHOL
what do you do with the contents of each flask
filter the contents of each flask and transfer some of each filtrate into a test tube
TO SHOW THE PRODUCTION OF ALCOHOL
what do you add to each tube?
some acidified potassium dichromate
TO SHOW THE PRODUCTION OF ALCOHOL
what do you finally do with the tubes
place in a water bath and heat gently
TO SHOW THE PRODUCTION OF ALCOHOL
yeast and glucose solution original colour
n
TO SHOW THE PRODUCTION OF ALCOHOL
yeast and glucose solution final colour
n
TO SHOW THE PRODUCTION OF ALCOHOL
control original colour
n
TO SHOW THE PRODUCTION OF ALCOHOL
control final colour
n
