Plants do breathe and require oxygen for respiration, producing carbon dioxide as a byproduct. Unlike animals, plants do not have specialized organs for gas exchange, but instead use stomata and lenticels. Each plant part is responsible for its own gas exchange at lower respiration rates than animals. Aerobic respiration utilizes oxygen to produce carbon dioxide, water, and energy from glucose. Glycolysis is the first step and breaks glucose down into two molecules that enter the payoff phase, producing two ATP molecules, two NADH molecules, and two pyruvate molecules as end products.

1. Do plants breathe?
Glycolysis

2. * Yes, plants require oxygen for
respiration and they also give
out carbon dioxide.
* Plants unlike animals does not
have any specialized organs for
gaseous exchange but they
have stomata and lenticels for
this purpose.

4.  Each plant part takes care of its own gas-
exchange needs.
 Roots, stems and leaves respire at rates far
lower than animals do.
 And also when cell photosynthesize,
availability of oxygen is not a problem as
oxygen is released within the cell itself.

5.  Aerobic respiration :
 During respiration oxygen is utilized and carbon
dioxide, water and energy are released as
products.
 Anaerobic respiration :
 Glucose (Broken down to) →Energy (ATP) +
Ethanol + Carbon dioxide .

6.  Glycolysis (
breakdown of
glucose ).
 Krebs cycle ( or
citric acid cycle ).
 ETC ( Electron
transport chain ).

7.  Glycolysis starts off with glucose { }.
 C-C-C-C-C-C
 There are two important phases of Glycolysis
as follows :
 1) INVESTMENT PHASE
 2) PAYOFF PHASE

8.  This phase uses 2 ATP’s.
 Since 2 ATP’s are used we call it as investment phase. [Business term]
 Then there is a breakdown of glucose into 2.3 carbon compounds.

 C-C-C-C-C-C

 C-C-C C-C-C ( They actually have a phosphate group on them that comes
from ATP’s.
 P-C-C-C C-C-C-P ( This is often referred to as PGAL [ phospho glycer
aldehyde]

9.  Now each of these 2 PGAL molecules enter the
payoff phase.
 In the payoff phase each of these PGAL’s turn into
pyruvates (or pyruvic acid ).
 P-C-C-C C-C-C-P
 C-C-C (pyruvate) C-C-C (pyruvate)
 ( 3 carbon compound )

10.  P-C-C-C C-C-C-P
 2 ATP’s 2ATP’s
 NADH+ NADH+
 C-C-C (pyruvate) C-C-C (pyruvate)
 ( 3 carbon compound )
 Production of 2 ATP’s and NADH+ takes place.
 NADH is a compound formed by NAD+ + H2
 It is produced by raw material NAD+ and then reduced
by adding hydrogen. Hence NAD+ gets reduced to
NADH.

11.  2 ATP’s
 2 NADH’s
 2 Pyruvates
 End or key product of glycolysis
is pyruvate.

14.  This depends on the cellular needs. There are 3 major ways in
which different cells handle pyruvic acid produced by glycolysis
that are :
 Lactic acid fermentation. (It is a biological process by which
glucose, fructose, and sucrose, are converted into cellular energy
and the metabolite lactate.)
 Alcoholic fermentation. (It is a biological process in which sugars
such as glucose, fructose, and sucrose are converted into cellular
energy and thereby produce ethanol and carbon dioxide as
metabolic waste products.)
 Aerobic respiration. (It is a chemical reaction is which oxygen is
used to break glucose down into carbon dioxide and water. Energy
is also released in this process.)

15.  http://www.youtube.com/watch?v=FOaXTjR
hV2E
 http://biology.about.com/od/cellularprocesse
s/a/aa082704a.htm
 http://www.youtube.com/watch?v=O5eMW4
b29rg

16.  PPT by Harmanpreet Kaur.