Respiration ncert Flashcards
All living organisms need — for carrying out daily life activities, be it absorption, transport, —-, reproduction or even —.
Where does all this energy come from?
energy
movement, breathing
The process of breathing is very much connected to the process of —- from food.
release of energy
All the energy required for ‘life’ processes is obtained by —– —– that we call ‘food’.
oxidation of
some macromolecules
Only —- and —- can prepare their own food; by the process of photosynthesis they trap light energy and convert it into —- energy that is stored in the bonds of carbohydrates like —-, —- and —-.
green plants and
cyanobacteria
chemical
glucose, sucrose and starch
In green plants, all cells, tissues and organs
photosynthesise. T/F
False
only cells containing chloroplasts, that are most often located in the superficial layers, carry out photosynthesis.
Food has to be translocated to all —-parts of a plant.
nongreen
Animals are — , i.e., they
directly (herbivores) or indirectly (carnivores).
heterotrophic
—- like fungi are
dependent on dead and decaying matter.
Saprophytes
Ultimately all the food that is respired for life processes comes from
—.
photosynthesis
Cellular respiration is —-
the mechanism of breakdown of food within the cell, by releasing energy and trapping it to form ATP
Photosynthesis, takes place within the —- (in the
eukaryotes), whereas the breakdown of complex molecules to yield energy
takes place in the — and — (also only in eukaryotes).
chloroplasts
cytoplasm and in the mitochondria
The breaking of the — of complex compounds
through — within the cells, leading to release of considerable amount of energy is called respiration.
C-C bonds
oxidation
The compounds that are oxidised during cellular respiration are known as —
respiratory substrates
Usually — are oxidised to release energy, but proteins, fats and even
—- can be used as respiratory substances in some plants, under
certain conditions.
carbohydrates
organic acids
During oxidation within a cell, all the energy contained in respiratory substrates is —- .
not released free into the cell, or in a single step
Energy from breakdown of food is released in a series of —- reactions controlled by — , and it is trapped as chemical energy in the form of ATP.
slow step-wise , enzymes
Energy released by oxidation in
respiration is used directly for other reactions in the body. T/F
False. It is used to
synthesise ATP, which is broken down whenever (and wherever) energy
needs to be utilised.
ATP acts as the —- of the cell.
energy currency
This energy trapped in ATP is utilised in various energy-requiring
processes of the organisms, and the —- produced during respiration is used as precursors for – of other molecules in the cell.
carbon skeleton, biosynthesis
Plants require —
for respiration to occur and they also give out –
O2, CO2
Plants have systems in place that ensure the availability of O2. T/F
True
Plants, unlike animals,
have no specialised organs for gaseous exchange but they have — and —- for this purpose.
stomata
and lenticels
Why can plants get along without respiratory organs?
- Each plant part takes care of its own gaseous needs- Transport is very lil.
- Low demands for gas exchange. Roots, stems and leaves- respire at lower rate than animals (except ps- which leaves take care of + already get O2)
- Distance that gases must diffuse even in large, bulky plants is not great.
Each living cell in a plant is located quite close to the — of the plant.
surface
In stems, the ‘living’ cells are organised in thin layers — and — the bark. They also have openings called —.
inside and beneath
lenticels
The cells in the interior of stem are dead and provide —.
only mechanical support
Most cells of a plant have at least a part of their surface in —. This
is also facilitated by the loose packing of —- in leaves, stems and roots, which provide an interconnected network of air spaces.
contact with air
parenchyma cells
The complete combustion of —, which produces CO2 and H2O as end products, yields energy most of which is —
glucose, given out as heat
If this energy is to be useful to the cell, it should be able to —- .
utilise it to synthesise other molecules that the cell requires
The strategy that the
plant cell uses is to — the glucose molecule in such a way that not all the liberated energy goes out as heat.
catabolise,
The key is to oxidise glucose not in one step but in —- enabling some steps to be just large enough such that the energy released can be —.
several small steps, coupled to ATP synthesis
The combustion
reaction requires —.
oxygen
But some cells live where oxygen may or may
not be available. There are reasons to believe that the —- that lacked oxygen.
first cells on this planet lived in an atmosphere
Among present-day living organisms, we know of several that are adapted
to — conditions.
anaerobic
Some of these organisms are — anaerobes, while in others the requirement for anaerobic condition is
—.
facultative, obligate
All living organisms retain the enzymatic machinery
to —- without the help of oxygen.
partially oxidise glucose
Breakdown of glucose to — acid is called —-.
pyruvic , glycolysis
The term glycolysis has originated from the —words, glycos for —,
and lysis for —.
Greek ,
sugar, splitting
The scheme of glycolysis was given by —, — and —, and is often referred to as the EMP pathway.
Gustav Embden, otto Meyerhof, J. Parnas
In anaerobic organisms, — is the only process in respiration.
Glycolysis
Glycolysis occurs in the —of the cell and is present in all living organisms.
cytoplasm
