Download Lecture 6 Photosynthesis and Cellular Respiration

Lecture 6
Photosynthesis
and Cellular
Respiration
1
What is Photosynthesis?
Photosynthesis is the process by which plants
use the energy from sunlight to produce sugar.
The conversion of sunlight energy into chemical
energy, is associated with the actions of the
green pigment Chlorophyll.
6H2O + 6CO2 ----------> C6H12O6+ 6O2
2
The chemical equation translates as:
Six molecules of water plus six molecules of carbon
dioxide produce one molecule of sugar plus six
molecules of oxygen.
Diagram of a typical plant,
showing the inputs and outputs
of the photosynthetic process
3
Plastids:
- It is a cellular structure present in
plants and algae while absent in animals.
- It is the center of anabolism (building)
and the production of food compounds in
the cell.
- Plastids are of 2 types, chloroplastids
that perform photosynthesis and
chromoplastids that give the flowers
and fruits their colours.
4
Zooming in on
the location of
photosynthesis
in a plant
mesophyll cell.
CELLULAR RESPIRATION
 Respiration: is a process in which organisms
breathe oxygen and excrete CO2 and water.
 Organic compound+O2→CO2 +water + energy
Carbohydrates, fats, and proteins can all be used as fuel
for cellular respiration.
CELLULAR RESPIRATION
 Cellular respiration: includes both aerobic &
anaerobic processes where fuel breaks down by
Mitochondria generating ATP.
 1- Aerobic respiration: when O2 is consumed as a
reactant along with organic fuel. It occurs in most cells
and release 36-38 ATP molecules as energy.
 2- Anaerobic respiration: No O2 is used, other
substances are reactants that are harvesting chemical
reaction. It occurs in prokaryotes and release lower
energy (about 2 ATP molecules).
Fermentation and Anaerobic Respiration
 Fermentation is a process where organic fuels
are oxidized and generate ATP without the use
of oxygen.
 Two types: Alcohol fermentation (yeast is used
in baking) & Lactic acid fermentation (Human
muscles)
The chemical elements essential to life are recycled
Photosynthesis generates
O2
and
organic
molecules
used
by
Mitochondria as fuel for
Cellular respiration.
The waste products
cellular respiration
CO2 and water which
the raw materials
Photosynthesis.
of
are
are
for
Quiz
1. Plants and animals exchange materials through the processes of
photosynthesis and respiration. Which of these statments is true
about the way these two processes are related?
 A. The products of photosynthesis inhibit respiration.
 B. The products of photosythesis are also the products of
respiration.
 C. The reactants of photosynthesis are also the reactants of
respiration.
 D. The product of photosynthesis are the reactants of respiration.
2. What is the main difference between aerobic and anaerobic
respiration?
 A. Aerobic uses sugar, Anaerobic does not
 B. Aerobic makes 2 ATP, Anaerobic makes 36 ATP
 C. Aerobic uses oxygen, Anaerobic does not
 D. Anaerobic uses oxygen, Aerobic does not
10
Quiz
3. Which of the following shows the products of photosynthesis?
 A. Oxygen and glucose
 B. Oxygen and carbon dioxide
 C. Water and carbon dioxide
 D. Glucose and water
4. Which of the following statements is most correct?
 A. Aerobic respiration occurs without oxygen and makes 2 ATP.
 B. Aerobic respiration occurs with oxygen and makes 36 ATP.
 C. Anaerobic respiration occurs with oxygen and makes 36 ATP.
 D. Anaerobic respiration occurs without oxygen and makes 36
ATP.
11
Quiz
5. What products of photosynthesis and reactants for
respiration belong in the box to complete the cycle?
 A. Hormones
 B. Chlorophyll a and chlorophyll b
 C. ATP and ADP
 D. Glucose and oxygen
6. Photosynthesis uses sunlight to convert water and carbon
dioxide into
 A. Oxygen
 B. High- energy sugars and starches
 C. ATP and oxygen
 D. Oxygen and high- energy sugars and starches
12
Quiz
7. What is found in a plant cell but not in a animal cell?
 A. Cell membrane
 B. Cytoplasm
 C. Chloroplasts
 D. Golgi apparatus
8. Photosynthesis is to chloroplasts as cellular respiration is to
 A. Chloroplasts
 B. Cytoplasm
 C. Mitochondria
 D. Nuclei
13