Second (2nd) Quarter Topics in Science 7

JADY CLAIRE J. LULLEGAO- SCIENCE TEACHER

Identify parts of the
microscope and their
functions; S7LT-IIa-1

MAJOR PARTS OF THE
MICROSCOPE
Magnifying Parts
Used to
enlarge
specimen
Used to
provide
light
Mechanical Parts
Used to
support
and
adjust
parts
Illuminating Parts

Stage Clip
Arm
Pillar
Iris Diaphragm
Draw Tube

PARTS AND FUNCTION OF A
COMPOUND MICROSCOPE
I. MAGNIFYING PARTS- used to enlarge the
specimen
1. Eyepiece
-an opening where one view’s the
specimen being observed
2. Objectives
- Metal, cylinders attached below the
nosepiece and contains especially ground
and polished lenses. It magnifies the
specimen in different levels.

Scanning Objective- gives 4x magnification
Low Power Objective (LPO)- gives the lowest
magnification, usually 10X.
High Power Objective (HPO)- gives higher
magnification, usually 40X or 43X.
Oil Immersion Objective – gives the highest
magnification, usually 97X, or 100X, and is used
wet either with cedar wood oil or synthetic oil.

COMPOUND MICROSCOPE
II. ILLUMINATING PARTS- used to provide
light
1. Mirror- supplies light
2. Condenser- used to collect and focus the
light from the illuminator on to the
specimen
3. Iris Diaphragm- controls the amount
of light reaching the specimen.

COMPOUND MICROSCOPE
III. MECHANICAL PARTS-used
to support and adjust the parts.
1. Revolving Nosepiece- it allows one to switch from one
objective to another.
2. Stage- it is a flat platform where the specimen is
placed.
3. Stage clips- it holds the glass slide in place
4. Arm- it connect the body tube to the base of the
microscope.
5. Coarse Adjustment- it is an adjustment to obtain
focus under LPO

6. Fine Adjustment- It is an adjustment for
focus under HPO.
7. Inclination Joint- It allows one to tilt the
microscope so viewing can be possible while
seated.
8. Base- It supports the microscope
9. Body Tube- it connects the eye piece to
the objectives.
10. Pillar- it connects the base to the arm.

It is the ability of a
microscope to
produce an image of
an object at a scale
larger (or even
smaller) than its
actual size.

Total Magnification= Magnification of
Eyepiece x Magnification of the
Objective
TM= ME x MO
To get the total magnification, you need to
multiply the magnification of the lenses of
the eyepiece and the objective.

Rasol wanted to know the
magnification of the image of the ant
he observed under the microscope. He
uses scanner and 10x eyepiece. What
is the total magnification of the image
of the ant?

Microscope: Parts and Functions
Magnification
Do’s and Don’t

Direction: Identify the following parts according to its
functions.
1. It supplies light.
2. It is an opening where one view’s the specimen
being observed
3. It allows one to tilt the microscope so viewing can be
possible while seated.
4. It gives the highest magnification, usually 97X, or
100X, and is used wet either with cedar wood oil or
synthetic oil.
5. It gives higher magnification, usually 40X or 43X.

ME MO TM
1 10X Scanner
(4X)
2 10X LPO(10X)
3 10X HPO
(40X)
4 15X LPO(10X)
5 15X HPO
Direction: Solve for the Total Magnification of the following
Microscope:

1. Always carry the microscope with one hand.
2. Place the microscope away from the edge of
the table with the arm facing toward you.
3. ONLY use towel to clean the lenses of the
microscope.
4. Don’t touch the lenses of the microscope with
your fingers.
5. Focus on low power and then switch to high
power.

6. PUT the microscope at the sun directly into the
sun as the light source.
7. The specimen being observed must be thick
enough to allow light to pass through it.
8. Avoid tilting the microscope while observing wet
mounts.
9. Prevent liquids, especially acids and alcohol
from spilling on any part of the microscope
10. Use one eye to look through the microscope and
close the other eye.

Stage Clip
Arm
Pillar
Iris Diaphragm
Draw Tube
1
2
3
4
5
6
7
8
9
10
10,11,12,13
14
15
15
16
17

Focus specimens using
the compound
microscope: S7LT-IIb-2

1. Always carry the microscope with two hands. One
goes under the base and the other holds the arm.
2. Place the microscope away from the edge of the
table with the arm facing toward you.
3. ONLY use lens paper to clean the lenses of the
microscope.
4. Keep slides and cover slips clean. Use anything
OTHER than lens paper to clean them.
5. Focus on low power and then switch to high
power.

6. When switching from one power to the next, store
the objective lens and eyepiece in plastic storage
container.
7. When moving the optical tube downward, always
look to the SIDE of the microscope to make sure
the PIN stops it from hitting the slide.
8. Use both eyes to look through the microscope.
9. Before putting the microscope away, always turn
the optical tube so it’s securely fastened into the
optical tube support.
10.Don’t touch the lenses of the microscope with
your fingers.

11. NEVER PUT the microscope at the sun directly
into the sun as the light source.
12. The specimen being observed must be thin
enough to allow light to pass through it.
13.Avoid tilting the microscope while observing wet
mounts.
14.Prevent liquids, especially acids and alcohol from
spilling on any part of the microscope
15.Check for moisture (such as from condensation of
human breath in the eyepiece.

1. Magnifying Parts
2. Illuminating Parts
3. Mechanical Parts
4. Magnification
5. Magnification Eyepiece x
Magnification Objective
(ME x MO)
6. 40x
7. 150x
8. 400x
9. 1500x
10. 15x
11. FALSE
12. TRUE
13. TRUE
14. TRUE
15. FALSE
16. FALSE
17. FALSE
18. TRUE
19. TRUE
20. FALSE

1. Magnification
2. TM= MO x ME
3. 100x
4. 60x
5. 400x
6. FALSE
7. TRUE
8. TRUE
9. TRUE
10.FALSE

For 1-5:
Name the things that will
be shown by your teacher.

6. Use only one eye in observing specimen.
7. Put the microscope on the edge of the table.
8. Use Lens Paper to clean the lenses.
9. Use directly the HPO to observe the specimen.
10. Prevent liquids, especially acids and alcohol
from spilling on any part of the microscope
Write TRUE if the statement is true , FALSE
if not.

1. Slide
2. Cover Slip
3. Lens Paper
4. Specimen
5. Wet Mounts
6. FALSE
7. FALSE
8. TRUE
9. FALSE
10. TRUE

Part or sample
of any material

Scalpels or Scalpel Handles are intended to be use with
surgical blades for tissue separation and other
procedure that require a sharp surgical blade to
puncture or cut.
Scalpel Handle No. 3

1. Place the prepared slide for observation on
the stage.
2. Make sure that the clips must firmly hold
the slides.
3. Positioned the low power objective using the
revolving nosepiece.
4. Then carefully lower the body tube until it
almost touches the slide using the coarse
adjustment knob.
5. The observer looks through the eyepiece

6. Slowly turn the coarse adjustment knob upwards
to raise the objective till a focus is obtained.
7. If a more detailed observation is desired, the
observer shift to the high power objective by
raising the body tube first.
8. Looking from the side, turn the revolving
nosepiece to put the HPO in place.
9. Then, using the fine adjustment knob, slowly
lower the objective till it almost touches the cover
slip.
10.Looking through the eyepiece, turn the fine
adjustment knob until you see the clearest image.

1. Cut a letter “e” I n the module.
2. Put the sample on the slide and put the slide on
the stage.
3. Make sure that the slide is on the center.
4. Then manipulate the coarse adjustment knob and
fine adjustment knob to attain clearer view.
5. Observe the spcimen.

Q1. Describe the position of the letter as seen
under the microscope.
Q2. Compare the image of the letter that you
see using your unaided eye with what you see
through the microscope.
Q3. To which direction does the image move?
Q4. Why do you have to watch from the side
when changing objectives?

Q5. Why should the fine adjustment knob be
used only with the HPO?
Q6. In which objective/s can you see the
whole letter “e”?
Q7. What are the advantages of using the
HPO? The disadvantages?
Q8. In which objective is the light darker?
Brighter?

1. Cut a thin sample of onion skin.
2. Put the sample on the slide and put the slide on
the stage.
3. Make sure that the slide is on the center.
4. Then manipulate the coarse adjustment knob and
fine adjustment knob to attain clearer view.
5. Observe the specimen.

1.Put one drop of water on the
slide.
2.Put it on the stage and observe
the sample.

Q1. Describe the position of the letter as seen
under the microscope.
Answer:
The position of the letter as seen under the
microscope is INVERTED.

Q2. Compare the image of the letter that you
see using your unaided eye with what you see
through the microscope.
Answer:
The image of the letter using the unaided
eye is smaller than using the microscope.
or
The image of the letter using the microscope is
larger than using only the eyes.

Q3. To which direction does the image move?
Answer:
The direction moves opposite.
(When you move the slide to the right, the
image move to the left, vice versa)

Q4. Why do you have to watch from the side
when changing objectives?
Answer:
To make sure that the objective is locked
and avoid the crashing of slide.

Q5. Why should the fine adjustment knob be
used only with the HPO?
Answer:
To avoid the crashing of the Slide.

Q6. In which objective/s can you see the
whole letter “e”?
Answer:
The objective that I can see the whole
letter “e” is the Scanner/Scanning Objective.

Q7. What are the advantages of using the
HPO? The disadvantages?
Answer:
The advantage of using the HPO is the image
is larger while the disadvantage is that you
can’t see the whole image of the letter “e”.

Q8. In which objective is the light darker?
Brighter?
Answer:
The objective that is a light darker is the HPO
or Oil Immersion while the objectives that are
brighter are the LPO and Scanner/Scanning
Objective.

Q30. How much is the letter “e” you are now
viewing under the scanner magnified? Under
the LPO? Under the HPO?
Q31. If a cell being observed has been
magnified 200x under a 40x HPO, what is the
magnifying power of the eyepiece used?
Q32. In what ways would the microscope
contribute to the study of different objects
and organisms?

1.Check the microscope before and
after use. Report any missing or
damaged part to your teacher.
2.Use a clean tissue paper or soft
cloth like old t-shirt to clean the
mechanical parts of the
microscope.

3. Prevent liquids, especially acids and
alcohol from spilling on any part of
the microscope. Always use a cover
slip in observing wet mounts.
4. Check for moisture (such as from
condensation of human breath) in
the eyepiece. This may happen due
to prolonged observation of
specimens. Wipe with lens paper.

5. Avoid tilting the microscope while observing
wet mounts. Water might flow into the
mechanical parts of the microscope causing
them to rust. Select a chair with suitable
height so that both forearms can be rested
on the table during observation.
6. Never store the microscopes in a chemical
laboratory or any place where there are
corrosive fumes. Make sure there are silica
get packs inside microscope boxes or storage
cabinet to absorb moisture.

Life is
complex,
yet it is
organized
atom
Molecule
Organelle
Cell
Tissue
Organ
Organ System
Organism
Population
Community
Ecosystem
Biome
Biosphere

Biological organization is based
on a hierarchy of structural
levels.
Each level of biological
organization has distinct
properties

1. ATOM
• The smallest unit of matter
that cannot be broken
down into anything simpler
by chemical means.
Examples:
Oxygen (O)
Nitrogen (N)
Neon (Ne)
Copper (Cu)

2. Molecules
• The smallest units of most
compounds formed that
retains its chemical
properties.
• Group of atoms
Examples:
DNA (𝐶15 𝐻31 𝑁3 𝑂13𝑃2)
Chloropyll (𝐶55𝐻72𝑀𝑔𝑁4𝑂5)
Water (𝐻2𝑂)
Salt (NaCl)

3. Organelles
• Specialized structures that
perform important cellular
functions within cells
• Group of molecules
Examples:
Chloroplast
Vacuole
Centrioles
Mitochondria

4. Cell
• The smallest unit of life –
collections of living matter
enclosed by a barrier that
separates them from their
surroundings.
• Group of organelles
Examples:
Animal Cell
Plant Cell
Nerve Cell
Red Blood Cell

5. Tissues
• Groups of similar cells that
perform a particular
function.
Examples:
Connective Tissue
Epithelial Tissue
Muscle Tissue
Nervous Tissue

6. Organs
• Groups of tissues that work
together to perform closely
related functions.
Examples:
Brain
Liver
Kidney
Bladder

7. Organ Systems
• Groups of organs that work
together to perform closely
related functions.
Examples:
Skeletal System
Muscular System
Digestive System
Respiratory System

8. Organisms
• Living things composed of cells
either unicellular or multicellular.
• Composed of organ systems.
Species =a group of organisms so
similar to one another that they can
breed and produce FERTILE
OFFSPRING.
Examples:
Human
Snake
Mushroom
Tree
Fish

9.Population
• Groups of organism of
the same species that
live in the same area.
Examples:
Pack (group of Wolves)
People (group of humans)
Pride (group of Lions)
Colony (group of ants)
Swarm (group of bees)

10. Community
• Groups different
populations that live
together in a defined
area.
Examples:
All the people and animals living
in Brgy. San Joaquin.

11.Ecosystem
• Groups of all the organisms
that live in a particular place,
together with their nonliving
environment.
Examples:
All the people and animals living
in Brgy. San Joaquin with the
different abiotic factors such as
soil, water, temperature and
moisture.

12. Biome
• Groups of ecosystems that
have the same climate and
similar dominant
communities
Examples:
Philippines is dominated with
the Biome of tropical
rainforest.

13. Biosphere
• Part of the Earth
in which life exists
including land,
water, air and
atmosphere.

13. Biosphere
• Part of the Earth in which
life exists including land,
water, air and atmosphere.

Objetives:
1. Identify parts of the cell;
2. Describe plant and animal cells;
3. Differentiate plant cells from animal cells;
4. Construct a Venn Diagram to show parts
that are common to both and parts that are
only found in either palnt or animal cells.

1. Compare the shape of a plant cell with
that of an animal cell as shown in
Figure 1 and 2.

2. parts are found in both
cells?
3. Which are present only in
animal cells?
4. Which are present only in
plant cells?

4. Which are present only in plant cells?
5. Based on your observations and study of
plant and animal cells, cite differences
and similarities between them.
6. What do you think will happen to the cell
if the plasma membrane does not
function properly?

7. What is the purpose of the cell wall in
plants?
8. Look at Figure 1 again. Why are there
several chloroplasts in the plant cell?
9. How would vacuoles in plants serve as
defense against animals that eat
them?

JADY CLAIRE J. LULLEGAO
Science Teacher

1.Identify plant cell
from animal cell.
2. Label the different
parts of the cell
3. Share how plant cell
different from animal
cell.

1. Differentiate plant and
animal cells according to
presence or absence of
certain organelles;
2. Explain why the cell is
considered the basic
structural an functional
unit of cell organisms

Animals like people, cats, fishes, and cows are all made up of
cells.
A typical animal cell has three distinct parts as seen under the
microscope: the plasma membrane, the cytoplasm and the
nucleus.
The plasma membrane is a thin sheet that encloses the cell. It is
through the plasma membrane where substances pass in and out
of the cell.
Cytoplasm contains many small, clearly defined structures called
organelles.
The nucleus is actually the largest organelle in animal cell.

All plants whether herbs, shrubs or
trees are made up of cells.
Plant cells are quite similar to
animal cells. They both have plasma
membrane, cytoplasm, nucleus and
other organelles.
There are important differences
between plant and animal cells.

Animal Cell
Centrioles
Small vacuole
Plant Cell
Chloroplasts
Cell wall
Large vacuole

CELL ORGANELLES AND
THEIR FUNCTIONS
1. Nucleus
-Contains the
cell’s DNA and is
the control center
of the cell.

CELL ORGANELLES AND
THEIR FUNCTIONS
2. Ribosome
-the site where
amino acids are
hooked together to
make proteins.

CELL ORGANELLES AND
THEIR FUNCTIONS
3. Endoplasmic Reticulum
-makes lipids, breaks down
drugs and other substances,
packages up proteins for release
from the cell. Serve as system
canals of the cell.
a. Rough ER- ribosomes
attached to it
b. Smooth ER- no ribosomes
attached

CELL ORGANELLES AND
THEIR FUNCTIONS
4. Mitochondrion
-break down food
molecules to make
ATP and serve as
the powerhouse of
the cell.

CELL ORGANELLES AND
THEIR FUNCTIONS
5. Chloroplasts
-make food using
the energy of
sunlight and site of
photosynthesis.

CELL ORGANELLES AND
THEIR FUNCTIONS
6. Golgi Complex
-part that packs
materials produced
by the cell in
vesicle/ vacuole.

CELL ORGANELLES AND
THEIR FUNCTIONS
7. Lysosomes
-digest food
particles, wastes,
and foreign
substances

CELL ORGANELLES AND
THEIR FUNCTIONS
8. Vacuole
-stores water,
nutrients and other
materials

CELL ORGANELLES AND
THEIR FUNCTIONS
9. Centrioles
-Plays an
important role
in cell division

CELL ORGANELLES AND
THEIR FUNCTIONS
10. Cell Membrane
-Controls the
passage of
substances going
in and out of the
cell

CELL ORGANELLES AND
THEIR FUNCTIONS
11. Cell Wall
-Gives shape
and
protection to
plant cells.

CELL ORGANELLES AND
THEIR FUNCTIONS
12. Cytoplasm
-part which is
where the different
organelles are
embedded.

ANIMAL CELL
Cilia and
Flagella
-responsible for
cell movement

CELL ORGANELLES AND
THEIR FUNCTIONS
1. Nucleus
-Contains the cell’s DNA and is the control center of the
cell.
2. Ribosome
-the site where amino acids are hooked together to make
proteins.
-makes lipids, breaks down drugs and other substances,
packages up proteins for release from the cell. Serve as
system canals of the cell.
a. Rough ER- with ribosomes attached to it
b. Smooth ER- no ribosomes attached

4. Mitochondrion
-break down food molecules to make ATP and serve
as the powerhouse of the cell.
5. Chloroplasts
-make food using the energy of sunlight and site of
photosynthesis.
6. Golgi Complex
-part that packs materials produced by the cell in vesicle/
vacuole.
7. Lysosomes
-digest food particles, wastes, and foreign substances

8. Vacuole
-stores water, nutrients and other materials
9. Centrioles
-Plays an important role in cell division
10. Cell Membrane
- Controls the passage of substances going in and out of
the cell.
11. Cell Wall
- Gives shape and protection to plant cells.
12. Cytoplasm
-part which is where the different organelles are
embedded.

2. Cell Wall
3. Lysosomes
4. Cell Membrane
5. Mitochondrion
6. Centrioles
7. Chloroplast
8. Nucleus
9. Ribosomes
10.Cytoplasm

What are the
organelles that is
present only in
PLANT CELL?

What is the
organelle that is
present only in
ANIMAL CELL?

What is the
difference between
animal and plant
cell in terms of
their VACUOLE?

It is the “control
center”
Cytoplasm Nucleus

It is where all the
organelles are
embedded
Mitochondria Cytoplasm

It stores water.
Vacuole Golgi Body

It is the site for
photosynthesis.
Cell Wall Chloroplast

It controls what comes
in and out of the cell
Cell Wall Cell Membrane

Nucleus
Cell Wall
Centrioles
Chloroplast
Cytoplasm
Ribosomes
Golgi Body
Large Vacuole
Plant Cell Animal Cell
Both

HISTORY AND DEVELOPMENT OF THE DISCOVERY
OF THE CELL

Explain why the cell is
considered the basic
structural and functional
unit of all organisms;

Basic unit of life that can
perform all activities
associated with life like
growth, reproduction,
excretion, and nutrition.

HISTORY OF CELL
Who is he?
He looked a thin
slice of cork under
his microscope
and discovered the
cell?

HISTORY OF CELL
Robert Hooke
He looked a thin
slice of cork under
his microscope
and discovered the
cell.

BEGINNING OF THE CELL THEORY
In 1838, a German
botanist named
Matthias Schleiden
concluded that all
plants were made
of cells
Schleiden is a
cofounder of the
cell theory

In 1839, a
German zoologist
named Theodore
Schwann
concluded that all
animals were
made of cells
Schwann also
cofounded the cell
theory

200
In 1855, a German
medical doctor named
Rudolph Virchow
observed, under the
microscope, cells
dividing
He reasoned that all
cells come from other
pre-existing cells by cell
division

CELL THEORY
1. All living things are made
of cells
2. Cells are the basic unit of
structure and function in
an organism (basic unit of
life)
3. Cells come from the
reproduction of existing
cells (cell division)

Identify beneficial
and harmful
microorganisms;
S7LT-IIF-6

Objectives:
1. Observe life forms other than those you studied from
Grades 3 through 6,
2. Use a magnifying lens to observe them
3. Share what you know about these life forms with
classmates and groupmates, and
4. Compare the with know living things studied in Grades
3 to 6.

Q1. Is it a palnt?
Q2. what is its name?
Q3. What is the reason for your
answer in Q1?

Q4. Is it a plant?
Q5. what is its name?
Q6. What is the reason for your
answer in Q4?

Q7. How are they differrent?
Q8. How are they alike?
Q9. Do you know of other living things like the
two above? If so, describe these living things.
Q10. How did you know about them?
Q11. Write their names if you know them.

Q12 What do you think it is?
Q13. Is it a plant?
Q14. Give a reason for your
answer in Q13.

Describe what you see in each
(a) and (b) or (c):
Q15. (a)
Q16. (b or c)

What do you think the growths
on (a), and (b) or (c) are?
Q18. (a)
Q19. (b) or (c)

How about (d), what do you
think it is?
Q20. (d)

ALGAE Unicellular or multicellular plant-like protist
that can make their own food.
BACTERIA Unicellular organisms that are used in
making fermented products act as
decomposers and may cause diseases.
FUNGI Big group of organisms that have plant-like
characteristics but cannot make their own
food.
LICHEN It is partly fungus and partly alga.
MUSHROOM A type of fungus that cannot make its own
food that can be used as food, act as
decomposers and some may cause diseases
like athlete’s foot.
PROTIST Big group of organisms having characteristics
of both plants and animals.
SPORES Seed-like structures of most fungi and some
algae used in reproducing their kind

Differentiate asexual from sexual
reproduction in terms of:
 1 Number of individuals
involved;
 2 Similarities of offspring to
parents

It is the transmission
of characteristics from
one generation to the
next generation.

Is the ability of an organism to
produce new individuals is one
of the characteristics that
distinguish living things from
nonliving things.

Objectives:
1. Describe how potatoes reproduce;
2. Explain what vegetative reproduction
is; and
3. Describe the advantages of growing
plants using vegetative reproduction.

Q1. Can you give a reason why it is better to plant
the cut pieces of potato with the “eye” pointing
upward?
Q2. How many “eyes” from each potato were you
able to get?
Q3. How many new shoots grew from each potato
“eye” you planted?
Q4. What is the advantage of using this type of
propagation?

I. Asexual Reproduction
- A type of reproduction that does not require the
union of sex cells.
II. Sexual Reproduction
- A type of reproduction that requires that union of
reproductive cells or gametes.

METHODS OF ASEXUAL
REPRODUCTION
1.Binary Fission
- is an equal division of nuclear
material and cytoplasm resulting into
new organisms.
Ex: amoeba, bacteria and euglena

2. Budding
-New individual may form as an
outgrowth of the parent. The
outgrowth separates from the parent
and becomes a new individual.
Ex: yeast, hydra and sponges

3. Spore Formation
-A type of asexual reproduction common
to fungi where fruit-like structures
called spores are released from spore
cases and each develops into a new
organism.
Ex: mold,fungi, mushroom, liverworts,
mosses and hornworts.

4. Regeneration
-Is the process in which
organisms replace or restore
their lost or damage body parts.
Ex: hydra, lizard, specific types
and starfish,

5. Fragmentation
-It is a form of asexual
reproduction where a new
organism grows from a fragment
of the parent
Ex: hydra, specific types and
starfish.

6. Parthenogenesis
-It is a form of reproduction that
does not involve a male gamete
and in which unfertilized egg
develops into a new individual.
Ex: Reptiles, amphibians and
some fishes

7. Vegetative Propagation
-It is an asexual propagation in
plants in which a new plant
grows from a fragment of the
parent plant or a specialized
reproductive structure.
Ex: most plants

MODES OF SEXUAL
REPRODUCTION
1. Conjugation
A type of sexual reproduction where the
content of one cell is transferred to
another cell to form a zygote by forming a
bridge between the two cells.
Ex: spirogyra (green alga)

2. Sexual reproduction in
FLOWERING PLANTS
- The flower is the
reproductive organ in
flowering plants. Flower have
structures that produce the
gametes necessary for
reproduction.

POLLINATION
Brings together the gametes of a flower and it
occurs when a pollen grain of the right kind lands
on the stigma of the pistil. Each pollen forms a
tube that grows down through the pistil and
reaches the ovule in the ovary. One of the nuclei in
the pollen tube unites with the egg nucleus in the
ovule to form a zygote. The other sperm nucleus
combines with two nuclei of the two polar cells in
the ovule which develops into the endosperm.

3 . Sexual reproduction in
ANIMALS
- The sperm and the egg
unite in a process called
fertilization.

3 . Sexual reproduction in HUMANS and
ANIMALS
A. External Fertilization
- Occurs outside the body of the organism.
Ex: fishes, amphibians, and aquatic vertebrates
B. Internal Fertilization
-occurs inside the female’s body. The male inserts
the sperm into the female.
Ex: mammals, insects, birds and reptiles

3. Sexual Reproduction in HUMANS AND ANIMALS
- Humans and all animals have reproductive cells called
gametes.
- Gametes are formed during meiosis and come in the form
sperm (produced by males) and eggs (produced by
females).
- Fertilization, the union of two cells forming a zygote.

Objective:
1. Distinguish the male and female
reproductive structures of a gumamela
flower, and
2. Describe the function of each structure in
reproduction

Q7. Describe how the flower is attached to the stem.
Q8. What is the function of the sepals in the
unopened flower?
Q9. On which flower does the stigma feels sticky?
Q10. Why do you think the stigma is sticky?
Q11. How many compartments do you find?
Q12. How do you think pollen grains reach the
ovary?

OBJECTIVES:
1. Identify the components of the
environment.
2. Compare the living and nonliving
things, and
3. Describe how organisms interact with
each other and with their environment.

Q1. What are the things that you see in
your school garden or the pond?
Q2. Which of these things are living?
Which of these things are nonliving?
Q3. Observe the things that you
identified as living. What do they have in
common?

Q4. Observe the things that you
identified as nonliving. What do they
have in common?
Q5. What interactions do you observe
happening among the living and
nonliving things?
Q6. What makes living things different
from nonliving things?

Q7. what do these small plants need that
is provided for by the rock?
Q8. where do you find these rocks that
are inhabited by small plants?
Q9. what other things in the environment
are inhabited by these small plants?
Where do you find these things?

Q10. why do you find them in these
places?
Q11. do you also see small plants growing
on the fences of your school?
Q12. What other living and nonliving
things did you see in the school garden or
the pond? Do you see them in other parts
of the school? Explain your answer.

Q13. do you know of a similar place near
your school where you see communities of
organism?
Q14. are the things you find in your
school garden or the pond the same
things that you find in the backyard of
your house? Explain your answer.
Q15. how do living things interact with
each other and with their environment?

ECOSYSTEM
SYMBIOTIC AND NON-SYMBIOTIC
RELATIONSHIP

REVIEW
 A(n) ___________ factor is a living (or once living)
component of an ecosystem.
 A(n) ___________ factor is a non-living component
of an ecosystem.
biotic
abiotic

REVIEW
 An ecosystem is the interaction between
__________ and __________ factors
abiotic biotic

describe the different
ecological relationships
found in an ecosystem;

SYMBIOSIS is the interaction between 2
different organisms living together
HOST- usually the LARGER of the 2
organisms
SYMBIONT- usually the SMALLER
member

A Symbiotic relationship in which one
organism lives at the expense of another.
One is benefit and one is harm.
Host – it lives on or inside another organism
Parasite – depends on another organism for
shelter and for food

Is a relationship between the host
and a symbiont, where both
organisms benefit and neither is
harmed.

Is a relationship between the
host and symbiont, where the
symbiont benefits and the host is
neither helped nor harmed.

capture and consumption of organisms by
other organisms to sustain life. One organism
is benefit and one is harm and died.
Predator – an animals that kills and eats other
animals
Prey – that animals that be eaten

Two or more organisms fight for
resources (food, space, shelter, a
mate), can be between same species
or different species.

ORGANISM #1 ORGANISM #2 TYPES OF RELATIONSHIP
BOA CONSRICTOR MOUSE
PREDATION
BENEFIT HARM / KILL

In this photo the “cleaner fish”
receives nourishment by dining
off of the parasites and
remaining food debris in the
eel’s mouth. Is this an example
of…
PARASITISM
MUTUALISM
COMMENSALISM

Clownfish are frequently found in
the tentacles of sea anemones. Sea
anemones capture their prey by
paralyzing them with their
tentacles. However, the clownfish
produces a mucus that prevents
the tentacles from harming it. By
dwelling amongst the tentacles the
clownfish receives a protected
home. This relationship is an
example of …
PARASITISM MUTUALISM COMMENSALISM

The birds in the picture are
munching on tiny parasitic
insects located on the rhino. The
relationship between the birds
and the rhino is an example of…
PARASITISM
MUTUALISM
COMMENSALISM

Lampreys are primitive fish with
limited digestive systems. They
attach to and feed on the body
fluids of fish with more advanced
digestive systems, often leading to
the death of the host fish. This
relationship is an example of…
PARASITISM
MUTUALISM
COMMENSALISM

Orchids grow on the branches
of high trees. These orchids get
more water and sunlight than
those on the ground. The tree is
unaffected by the orchid’s
presence. This relationship is an
example of…
PARASITISM
MUTUALISM
COMMENSALISM

Trapjaw Ant
A highly specialized predator, the trapjaw ant stalks its prey with spring-loaded jaws.
The trap is sprung when the ant detects prey with its antennae. Once the prey is
grasped, the ant thrusts its abdomen forward and injects venom to further subdue the
struggling quarry. This species, Acanthognathus teledectus, feeds exclusively on
springtails, tiny soft-bodied insects. These ants live in hollow twigs in small colonies of 4
to 20 individuals. They inhabit the rain forests of Central America. Ants outnumber all
other kinds of animals and play a critical role in ecology. They help control other species,
distribute seeds, and serve as food for larger animals.

Honeypot Ants Tending Aphids
Honeypot ants tend their aphids and periodically “milk” them for their
honeydew secretions by stroking the aphids gently with their antennae.
Ants will aggressively protect their aphids and may even move them
when they are in danger, transferring them into temporary shelters or
new nests. Some ant species also move their aphids into underground
burrows during the winter months.

Imperial Shrimp
The brilliant-red coloring of the imperial shrimp
matches the coloring of the Spanish-dancer sea slug,
on which it lives. The shrimp feeds on plankton and
detritus that get caught in the mucous covering of the
host’s skin.

Clownfish in Sea Anemone
Clownfish have a symbiotic relationship with sea anemones.
The fish chases away the anemone’s would-be predators with
its territorial behavior; and the anemone protects the fish with
its stinging cells. The fish is protected from the cells’ poison by
a thick mucous coat it secretes.

Blood Flukes
This light micrograph reveals adult intestinal Schistosoma mansoni, one of the species of
blood flukes that cause the disease known as schistosomiasis. The males are thick and
blue; the females are thin and clear. A type of flatworm, while in larval form blood flukes
enter the bloodstreams of people or animals exposed to contaminated water in tropical and
subtropical climates, and then lay their eggs inside the host’s body. The disease’s
symptoms, which include diarrhea, inflammation, and hemorrhage, vary in humans
depending on the species of fluke and what part of the body it infests. The disease may be
fatal if untreated.

White-Tailed Anemone Fish
The tiny white-tailed anemone fish helps clean
the anemone it lives in. It avoids being stung by
secreting a thick mucous coat that protects
against the stinging cells of the host anemone.

Sea Lamprey Clings to a Fish
The sea lamprey, a vertebrate parasite, belongs to the most primitive
group of living fish, the agnathans, or jawless fish. In this species the
lower jaw is missing and the upper jaw is modified into a sucking disk.
The lamprey feeds on blood by using this disk to attach to another fish
and drilling a small hole into the fish’s side with its small, muscular
tongue. The parasitic action rarely kills the host, but wounds caused by
lampreys often become infected.

Rain Forest, Costa Rica
Each year logging and agriculture destroy rain-forest terrain equal in size
to the state of Massachusetts (United States), threatening the survival of
tropical rain forests throughout the world. Located in a narrow belt within
four or five degrees of the equator, rain forests often provide the only home
for thousands of known or as yet undiscovered species of animals and
plants. The destruction of these rain forests is eliminating many of these
irreplaceable species at an alarming rate.

OBJECTIVES:
1. Identify the predators and prey animals in the
environment.
2. Describe how the predators capture the prey
animals for food, and
3. Describe how predators and prey animals interact
with each other in the environment.

PHOTOSYNTHESIS
- Process where plants are capable of converting energy form the Sun
into chemical energy in the form of glucose (food).

Arrange the following organisms to
show who eats whom:
killer whale
cod fish
krill shrimp
algae
leopard seal

What might happen to the other organisms if algae
were removed from this group?
What might happen if the killer whales were
removed?
Are there any organisms in this group that eat
more than one kind of food?

Producer (Autotroph)
Make their own food (usually through
photosynthesis)
Ex: plants (even the Venus Flytrap!)

 Consumers (Heterotroph)
 Can’t make its own food
 Gets energy from eating other organisms
1. Herbivores – eats plants
2. Carnivores – eats animals
3. Omnivores – eats plants & animals
• Scavengers – eats dead animals

Decomposers
Break down waste and dead organisms to return
raw materials to the environment
Ex: bacteria, fungi, worms

Venus flytrap – producer
Fly - consumer

 Food chain – shows one path of the flow of
energy in an ecosystem
 Order of the food chain:
1.Sun – energy source
2.Producer
3.1st level Consumer – eats producers
4.2nd level Consumer – eats 1st level consumers
5.Decomposer – recycles materials for use by producers

– a model that shows the
energy flow through
different organisms in an
ecosystem.
consists of many
overlapping food chains in
an ecosystem

-describes the feeding relationship
between a producer and a single chain of
consumers in an ecosystem.

1. Producers
2. 1st Level (Primary)
Consumers
3. 2nd Level (Secondary)
Consumers
4. 3rd Level (Tertiary)
Consumers
5. 4th Level
(Quaternary)
Consumers

A pyramid is used to illustrate the
structure of the trophic levels in a food
chain.
3 types of ecological pyramids:
Pyramid of numbers
Biomass pyramid
Energy pyramid

Typically pyramid shaped, with the
largest number of organisms at the
producer level:

Shows the amount of living matter in a food chain.
Total dry weight (without water) of
organisms in a food chain
Mass/Area
Example: g/m2

When an organism eats, it obtains energy, then
uses a lot of energy in life process like growth and
movement.
This means that only part of their energy is
available to the next organism in the food web.

Illustrates the amount of energy that
moves from one feeding level to
another in a food chain or web
The greatest amount of energy is
available at the producer level
The least amount of energy available to
going to be a the top of the food chain.
Only about 10% of the trophic level’s
energy is transferred to the next level.

Second (2nd) Quarter Topics in Science 7

Second (2nd) Quarter Topics in Science 7

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