Republic of the Philippines
DEPARTMENT OF EDUCATION
Region VII, Central Visayas
Division of Negros Oriental
CAWITAN HIGH SCHOOL
Cawitan, Sta. Catalina, Negros Oriental
EARTH AND LIFE SCIENCE
Grade Level: 11
Session: 1st Semester
Date: Prepared by:
07:45am-8:45am (11B) MTWTH SECOND Quarter
September 16,2019- MONDAY MR. REYNALD M. MANZANO
03:00pm-04:00pm (11A) MTWTH
SST-II
I. OBJECTIVES The learners demonstrate an understanding of the cell as the basic unit of life; how
photosynthetic organisms capture light energy to form sugar molecules; how organisms obtain
Content Standard:
and utilize energy.
The learners shall be able to make a poster that shows the complementary relationship of
Performance Standard:
photosynthesis and cellular respiration.
LC Code #: S11/12LT-IIbd-4; S11/12LT-IIbd-5; S11/12LT-IIbd-6; S11/12LT-IIbd-7; S11/12LT-IIbd-8
Learning
At the end of the session, the students will be able to:
Competency:
-Explain how cells carry out functions required for life.
K -Explain how photosynthetic organisms use light energy to combine carbon dioxide and water
to form energy-rich compounds.
-Trace the energy flow from the environment to the cells.
S
-Describe how organisms obtain and utilize energy.
A - Recognize that organisms require energy to carry out functions required for life.
II. SUBJECT MATTER
BIOENERGETICS
Content:
Learning Sources: Earth and Life Science (DIWA) pp. 104-115, Curriculum Guide pp. 5-6
Materials: Visual Aids, Book, Laptop and Projector
III. PROCEDURE
Motivation:
-Think of an industry or a company that has been around for so many years. It could be one
A. PREPARATION that you have heard your parents and grandparents talk about a lot because they have known
it most of their lives. What could be the reason for its success or its long life? What could be
the secret behind its success?
B. PRESENTATION
-LESSON DISCUSSION-
The Basic Unit of Life
All organisms are made up of cells. The cell is the basic structural unit found in every living
organism that performs several functions throughout life. The zoo animals such as elephants
and snakes, the plants in the garden, and even yourself, are all living things composed of cells.
These cells can only be seen through the use of a microscope.
Eukaryotic and Prokaryotic Cells
There are two types of cells based on the presence or absence of a nucleus. Cells can be
eukaryotic or prokaryotic.
Eukaryotic cells have a nucleus which contains the genetic material or DNA. They also have
several membrane-bound organelles such as ribosomes and mitochondria. They include
animal and plant cells.
Prokaryotic cells differ in eukaryotic cells because their DNA is found in a region called
the nucleoid rather than a nucleus. They also lack most membrane-bound organelles present
in eukaryotes. However, prokaryotes have cytoplasm where organelles are
suspended, flagella that aids in motility, cell wall made of peptidogycan, cell membrane that
serves as a selective barrier, and ribosomes that make proteins.
Eukaryotic Cells
There are two types of eukaryotic cells: animal and plant cells.
Animal Cells
Aside from the nucleus, the typical animal cell also have other membrane-bound organelles
such as mitochondria, lysosomes, Golgi apparatus, endoplasmic reticulum, nucleus,
microtubules, plasma membrane, cytoplasm, and ribosomes.
The mitochondria is the powerhouse of the cell because this is where most energy
(ATP) is produced.
The lysosomes break down large molecules into smaller pieces and digest worn out
organelles.
The Golgi apparatus sorts and packages proteins and lipids produced by the smooth
and rough endoplasmic reticulum.
o The cis face receives the materials for processing in transport vesicles.
o The trans face is the discharging end where molecules are released through
the secretory vesicles.
The endoplasmic reticulum has two types: rough ER and smooth ER.
o Rough endoplasmic reticulum is bounded with ribosomes. It is where most
protein synthesis occurs.
o Smooth endoplasmic reticulum has no ribosomes attached. Its function is
mainly for lipid synthesis.
The nucleus is the largest organelle that serves as the control center of the cell. It
contains the hereditary material known as DNA.
The microtubules are components of the cytoskeleton and important in a number of
cellular processes.
The plasma membrane is a semi-permeable membrane that encloses the cell
separating its contents from the surroundings.
The cytoplasm is a semifluid matrix where organelles are suspended.
The ribosomes consist of the large and small subunits. Their main role is to synthesize
proteins needed by the cell.
Plant Cells
Plant and animal cells share the same structures except for the chloroplast, cell wall, and
amyloplast, which are only found in plants. A large vacuole is found in both animal and plant
cells but is a typical and distinct structure in a plant cell.
The cell wall provides support and protection for the cell. Special openings
called plasmodesmata are used to communicate and transport materials between
plant cells.
The chloroplasts convert light energy to sugars through photosynthesis.
The vacuole is responsible for storing food, water, and metabolic and toxic wastes.
The amyloplast is responsible for the production and storage of starch and the
conversion of starch back to sugar as needed by the plant for energy.
How do cells carry out functions required for life?
Cells have different types which are specialized to perform specific functions. For example,
cardiac muscle cells have numerous mitochondrion because they need a lot of energy. Nerve
cells are long for them to be able to transmit signals from the brain to the rest of the body. Cell
membrane of cells in the intestine is extended to have more surface area to absorb food.
Mammalian red blood cells don’t have nucleus to make more room for hemoglobin, a protein
that carries respiratory gases.
Photosynthesis is the process where photosynthetic organisms convert light energy to
form sugar. In plants, photosynthesis specifically occurs in the leaves.
The thylakoid membrane contains chlorophyll which is responsible for capturing light energy.
Photosynthesis has two phases: light-dependent reaction and light-independent reaction.
Light-Dependent Reaction
The reaction occurs in the thylakoids. It converts light energy to ATP and NADPH. It can be
summarized into four steps:
1. Light absorption and splitting of water. Light strikes the chlorophyll and an enzyme
splits water (H2O) into protons (H+ions), electrons, and oxygen (O2).
2. Production of ATP. ATP synthase accepts energy from H+ions to produce adenosine
triphosphate (ATP).
3. Hydrogen pump powered by electron acceptors. Electrons pass through proton
pump and the energy from the electrons pumps H+ions back to the thylakoids.
4. Production of NADPH by re-energizing electrons. Light strikes again, the chlorophyll
and electrons get re-energized. The last electron acceptor moves electrons to
nicotinamide adenine dinucleotide phosphate (NADP) and H+ions to produce NADPH.
Light-Independent Reaction
This is also known as the Calvin cycle. It takes place in the stroma and
uses ATP and NADPH from the light-dependent reaction. It reduces CO2 to form sugar. The
reaction is summarized below.
1. Fixation of CO2. Ribulose bisphosphate carboxylase (Rubisco) catalyzes CO2 to
ribulose 1, 5-bisphosphate (RuBP). A carbon atom sticks to RuBP and results to
unstable 6-C molecule and splits into 3-phosphoglycerate.
2. Reduction of 3-phosphoglycerate. The energy from ATP and hydrogens from NADPH
are added to the 3-C molecule to form 3-phosphoglyceraldehyde (G3P).
3. Regeneration of RuBP from G3P. Most of the G3P are used to generate back the
RuBP and prepares again for CO2 fixation.
Photosynthesis is composed of two reactions. Below is the summary:
The Energy Flow from Environment to Cells
Energy that organisms use comes from food. Organisms can either make their own food
(autotrophs) or get it by consuming other organisms (heterotrophs). Examples of autotrophs
include plants and photosynthetic organisms such as algae. Examples of heterotrophs include
animals and humans.
Most autotrophs, such as plants, phytoplankton, and algae, capture light energy and take in
carbon dioxide and water from the environment. The reactants (CO2 and H2O) are then
converted into glucose. In addition, oxygen is released as a by-product. This process is known
as photosynthesis which occurs in the cell’s chloroplast. Since autotrophs can make their own
food, they are also called producers.
On the other hand, heterotrophs cannot make their own food so they depend on other
organisms for food. Some consume autotrophs (herbivores) while others consume other
heterotrophs (carnivores) or consume both (omnivores). Since they obtain energy from
consuming other organisms, they are also called consumers. The cells of heterotrophs produce
ATP (energy-carrying molecule) by breaking the chemical bonds in glucose and releasing their
stored energy. This process is known as cellular respiration which occurs in the mitochondria
of each cell.
Photosynthesis in autotrophs and cellular respiration in heterotrophs work together to store
and release energy in living organisms. The reactants of one process are the products of the
other. The reactants of photosynthesis – CO2 and H2O produce C6H12O6 and H2O. These
products are then used by heterotrophs in cellular respiration which
releases CO2 and H2O back to the
environment.
Energy Flow from Environment to Cells
As energy moves among living organisms,
some of it is lost as heat. Nevertheless,
that energy is not completely lost in the
universe. Energy is never created nor
destroyed. It is just converted from one
form to another. One good example is
when you feel hot after exercise. The
warmth that you feel in your body results
from energy transformation that occurs
when you move. As shown in the
illustration, loss of energy in the form of
heat and body activities is involved at
each step of energy transfer among
organisms.
The illustration above shows the overall flow of energy through living organisms. The solar
energy is captured by chlorophyll in the chloroplast of plant cells (producers). Through
photosynthesis, glucose is produced. Animals could then use this glucose from producers to
make their own energy through cellular respiration. This process occurs in the mitochondria of
animal cells. As energy is transferred, some energy is lost in the form of heat through different
activities of the body.
How Organisms Obtain and Utilize Energy
Carbohydrates are one of the most important food sources for animals. If carbohydrates are
stored, then its potential as a source of energy is null. Carbohydrates must be broken down
into sugar and produce ATP that will act as a fuel essential for cell's activities and processes.
The same thing happens when you put a coin in a machine slot, the machine slot will not
accept it unless it is a token because the machine slot was made to read the token, not the
coin.
Cellular Respiration
Cellular respiration is a process of energy conversion where carbohydrates are broken down
into glucose and ATP. There are two types of cellular respiration: aerobic
respiration and anaerobic respiration.
Aerobic Respiration
This occurs when glucose is broken down in the presence of oxygen. This is divided into three
stages: glycolysis, Kreb's cycle, and oxidative phosphorylation.
A. Glycolysis
t is a process where glucose is broken down into pyruvic acids.
It takes place in the cytoplasm.
Two ATP and NADPH are produced.
This can happen with or without oxygen.
C. Kreb's Cycle
This happens in
the mitochondria.
Kreb's cycle requires oxygen.
When a pyruvic acid
loses CO2, it produces acetyl-
CoA which oxidizes to
form CO2, ATP, and other
compounds (NADH and
FADH2).
D. Oxidative phosphorylation
Phosphorylation is the
process where electrons
are combined with another
molecule from the ATP.
The main goal is to transfer
electrons from NADH and
FADH2 to produce ATP.
The final electron acceptor
in oxidative
phosphorylation is the
oxygen. The oxygen accepts
the electrons to produce
water within the
mitochondrial matrix.
Two steps are involved: electron transport chain (ETC) and chemiosmosis.
ETC transports electrons but produces no ATP.
In chemiosmosis, ATP synthase is driven by protons to produce ATP.
Anaerobic Respiration
This occurs in the absence of oxygen and glucose is broken down to ATP. There are two types
of anaerobic respiration: alcoholic fermentation and lactic acid fermentation.
A. Alcoholic Fermentation
Glucose is converted to alcohol. This type of fermentation does not occur in humans. It usually
occurs in bacteria and yeast.
B. Lactic Acid Fermentation
This occurs in the human body when oxygen in the muscles is used up and the
muscles still require more energy, thus producing lactic acid. This is especially evident
during intense physical exercises or movements.
Group Activity:
E. PRACTICE 5 student per group
Make a poster that shows the complementary relationship of photosynthesis and cellular
respiration
IV. ASSESSMENT Give a short quiz. Ask the following questions: (10 points)
1. What is the advantage of producing NADPH and ATP in thylakoid member?
2. Why is light important in photosynthesis?
3. What happens during the light-dependent reaction and during the light independent
reaction?
4. What energy source drives ATP production?
5. What is the net molecular product in glycolysis?
6. How can the cell harness energy to make ATP?
V. ASSIGNMENT
Research and study the following. Write your idea on your notebook
1. Plant and animal reproduction
2. How genes work
3. How genetic engineering is used to produce novel product.
VI. REMARKS
