Gulf Asian English School (Alarmelu Natchiar)

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.