1) The document is an instructional plan for teaching 8th grade students about the digestive system and related processes of ingestion, absorption, assimilation, and excretion. 2) It provides learning objectives, key concepts, materials, and a step-by-step procedure for a lesson engaging students in explaining these processes through a video, diagram matching, and worksheet. 3) The lesson guides students to trace the movement of food through each process from ingestion in the mouth to excretion from the anus and defines each process.

1. Republic of the Philippines
Department of Education
Region IX, Zamboanga Peninsula
DIVISION OF ZAMBOANGACITY
Baliwasan Chico,Zamboanga City
INSTRUCTIONAL PLAN IN SCIENCE 8
Grade Level Eight (8) Date:
Quarter Fourth Quarter Time Allotment: Good for 1 Hour
Content
Standard
The learners demonstrate understanding of the digestive system
and its interaction with the circulatory, respiratory and excretory
systems in providing the body with nutrients for energy.
Performance
Standard
The learners should be able to present an analysis of the data
gathered on diseases resulting from nutrient deficiency.
Learning
Competency
Explain ingestion, absorption, assimilation and excretion. (S8LT-
IVa-13)
I. Learning
Objective
The Grade 8 learners are expected to:
Explain ingestion absorption assimilation and excretion
II. Subject
Matter
Digestive System
A. Concepts 1. Ingestion – the act of taking in food through the mouth
2. Absorption – The process of taking digested food from the
small intestine into the blood stream so they can be used in
the body.
3. Assimilation – refers to the movement of digested food
molecules into cells in the body where it will be used as a
source of energy or nutrient.
4. Excretion – involves the removal of undigested food
contents or metabolic wastes from the body.
B. Materials Blank diagram of digestive system
Video on Digestive Procesess
C. References Department of Education. (2016). K to 12 Curriculum Guide
SCIENCE (Grades 3 - 10)
D. Process
Skills
Listening, Note Taking, Comparing, Identifying
E. Values
Integration
Active listening and participation
III. Procedure
A. Engage
(I DO)
Say, “We get nutrients and energy from the food that we eat.
However, our food is so much bigger compared to our cells. Thus,
to be able to get the nutrients present in the food, there is a need to
break down the food into smaller pieces and into its soluble form so
that it can be made available to the cell. That is the function of the
digestive system. I have here the diagram of the digestive system
and its organs. When you eat, the food first pass in the mouth, then
in the esophagus, stomach and small intestine. While the food that

2. is not completely digested goes to the large intestine. You have
learned the process of digestion when you were in elementary.”
“This time we will look at other processes that are related to
digestion. At the end of this lesson, you are expected to explain
ingestion, absorption, assimilation and excretion.”
B. Explore
(I Do)
C. Explain
(We Do)
“I will show you a video about these digestive processes”.
So from the video we have learned the following:
1. Ingestion – the act of taking in food through the mouth
2. Digestion – is the breakdown of food
3. Absorption – The process of taking digested food from the
small intestine into the blood stream so they can be used in
the body.
4. Assimilation – refers to the movement of digested food
molecules into cells in the body where it will be used as a
source of energy or nutrient.
5. Excretion – involves the removal of undigested food
contents or metabolic wastes from the body.
“Let us now match the four processes to the part where it occurs.
Who can come to the board and match the process to the part
where it takes place?”
(esophagus)
(mouth)
(small intestine)
(stomach)
(large intestine)
(rectum)
(Ingestion) (Excretion)
(Assimilation)
(Excretion)

3. (Expected answer)
Guided Discussion
 What is ingestion? (It is the act of taking in food through the
mouth)
 What is the next step after the food is completely digested?
(absorption)
 What do you call the cells in the small intestine that are
specialized for absorption? (villi)
 What happen during assimilation? (the food molecules into
cells in the body where it will be used as a source of energy
or nutrient)
 Where do the undigested food go? (large intestine)
 Can it be used by the cell? (No, because it is not yet
completely digested).
 What does our body do with undigested food?” (It will be
removed through the process of excretion.)
 The large intestine will absorb the water that goes with the
undigested food. This undigested food forms the feces
which will move to the last part of the large intestine called
the rectum. The rectum triggers the defecation reflex that
signals you when you have to go to the bathroom. From the
rectum the feces will move out of the body through a small
opening called the rectum.
“Let u now trace the movement of food in each of the four
processes:”
 Ingestion is the act of placing the food in the mouth. Thus,
food moves from where (outside the body)__ then into
your __(mouth)___
 When food is completely digested it will then be absorbed.
Digested food will be transferred transfer from ___(small
intestine)__ to your _(blood stream)__
 The digested food will be transported to all cells in the body.
Thus during assimilation, food moves from ____________
to the ___________
 Food that is not completely digested can not be used by the
cells of our body. Since its of no use, the body will get rid of
it. During excretion, undigested food will move from the
___________ going ______________ through the rectum.
(Ingestion)
(Excretion)
(Absorption)
(Assimilation)

4. D. Elaborate
(You Do)
Independent Practice
(Distribute worksheets to the students)
Arrange the following in order as they take place in the body, place
it in the arrow box. Above each arrow box, name the process
involved.
 Undigested food is removed from the body through the anus
 Food is placed in the mouth
 Digested food moves into the blood stream.
 The food is broken down into their soluble form.
 Digested food moves into the cell where it will be used as a
source of energy or nutrient.
2.
1.
3.
4.
_____________
5.
_____________
_____________
_
_____________
______________

5. E. Evaluate
(You Do)
Expected Answer
Write the letter of your answer in ¼ sheet of paper.
1. Ingestion is ____
a. The process by which materials that are not digested are
thrown out of the body.
b. The process by which the food absorbed by the cells is
used to produce energy.
c. The process by which the body breaks down the food.
d. The process by which an organism takes in food.
2. The process by which absorbed nutrients become part of
the body is called ____ .
a. digestion
b. ingestion
c. assimilation
d. excretion
3. Which of the following shows correct sequence of processes
involved in Digestive System?

6. V. Assignment
a. Absorption, Assimilation, Ingestion, Excretion
b. Ingestion, Absorption, Assimilation, Excretion
c. Ingestion, Assimilation, Absorption, Excretion
d. Assimilation, Absorption, Ingestion, Excretion
4. Ingestion is the taking in of food while __________ is the
removal of undigested food.
a. digestion b. absorption c. assimilation d. excretion
5. The transfer of food from the bloodstream into the cell is
called
a. ingestion b. absorption c. assimilation d. excretion
Explain how digestive system coordinate with circulatory
respiratory n excretory system.
Prepared by
SHARON A. VELOSO
Maria Clara L. Lobregat National High School