Transcript Cellular Respiration

Cellular
Respiration
By: Katie Cameron & Analise
Fagan 
Cellular Respiration:
• Cellular respiration is the process of
oxidizing food molecules, like glucose, to
carbon dioxide and water. The energy
released is trapped in the form of ATP for
use by all the energy-consuming activities
of the cell.
ENERGY:
• Most of the energy
we get comes from
the foods we eat. It
comes from
carbohydrates,
proteins, and fats
but before you can
use this energy it
has to be
transferred through
ATP by Cellular
Respiration.
Aerobic & Anaerobic:
• Aerobic metabolic
processes require
oxygen.
• Anaerobic
metabolic
processes don’t
require oxygen.
The stages
• Stage one:
– When glucose is
converted to
pyruvate, and a
small amount of
ATP and NADH is
produced.
Continued
• Stage two:
– When oxygen is present pyruvate and
NADH are used to make a large amount
of ATP during aerobic respiration.
This occurs in the mitochondria of a
eukaryotic cell and the membrane of
the prokaryotic cell.
– When there is no oxygen present
pyruvate is converted to lactate or
ethanol and carbon dioxide.
Krebs cycle:
• The Krebs cycle
is a series of
enzyme assisted
reactions
• Named after Hans
Krebs in 1937
• Produces electron
carriers that
temporarily store
chemical energy
Krebs Cyle: Step 1
• Acetyl-CoA combines with a fourcarbon compound, forming a sixcarbon compound and releasing
coenzyme A.
Krebs Cycle: Step 2
• Carbon dioxide, CO2, is released
from the six-carbon compound,
forming a five-carbon compound.
Electrons are transferred to NAD+,
making a molecule of NAHD.
Krebs Cycle: Stage 3
• Carbon dioxide is released from
the five- carbon compound,
resulting in a four-carbon
compound. A molecule of ATP is
made, and a molecule of NADH is
also produced.
Krebs Cycle: Part 4
• The existing four- carbon compound
is converted to a new four- carbon
compound. Electrons are
transferred to an electron
acceptor called FAD, making a
molecule of FADH2.
Krebs Cyle: Part 5
• The new four-carbon compound that is
created is then changed to the same fourcarbon compound that started the cycle
• Anther molecule of NADH is produced too.
Respiration in the absence of
oxygen
• When there is not enough oxygen for
aerobic respiration to occur the electron
transport chain does not function.
• This means that the electrons are not
recycled.
Fermentation
• Fermentation is the
recycling of NAD+
using an organic
hydrogen acceptor
Lactic Acid Fermentation
• A three carbon pyruvate is converted to a
three carbon lactate through lactate acid
fermentation.
• This enables glycolysis to produce ATP as
long as the glucose supply lasts during
something such as vigorous exercise.
Alcoholic Fermentation
• The process in which a three carbon
pyruvate is broken down into ethanol, a
two carbon compound through alcoholic
fermentation.
• First pyruvate is converted to a two carbon
compound releasing carbon dioxide.
Secon electron are transferred from NAHD
to the two carbon compound, producing
ethanol.
Electron Transport Chain
• Also known as the
respiratory chain. It is
composed of the
mitochondrial
enzymes that transfer
electrons from one
complex to another,
eventually resulting in
the formation of
ATP.