Topic
: Chapter 3; Homeostasis
Sub-topic
: Homeostasis in human
Teaching
& Learning Strategies : Contextual Learning, outdoor activities
Students'
Activities
: Simple physical activities, group
discussion
Introduction
Homeostasis
is a new topic in KSSM Science Form 1. Previously in KBSM, homeostasis is only taught
to form 5 students. So, when I first heard about this topic, even I was
nervous. Don’t even remember whether I ever learnt it before this in Biology or
not. Totally forgot and no idea. Haha…
For
me, the concept of homeostasis is too abstract, especially the explanations. When
I first taught the students, they were all blurr. They can understand the
basics, but when they need to explain, their mind ‘blank’.
Therefore,
I use another learning session to repeat this topic by using different learning
strategies. Instead of just sitting in the classroom, see the video / power
point, this time I asked them to experience the homeostasis themselves. All the learning activities were done outside the classroom (at the volleyball court)
Induction
Set
I
asked students whether they ever took their pulse rate or whether they know the
normal rate of pulse. Two third of the students answered NO.
Then,
I asked the students to measure their pulse rate in one minute.
After
that, asked some students to share their pulse rate. Some of them got very low
(around 40-50) and some of them got more than 100.
I
asked students to give some idea why do they think the value is different from
one another and some of them have bigger difference.
Warm-up
Students
were asked to jog around the volleyball court for 3 laps.
After
that, they were asked to measure their pulse rate again and compare the value
with the previous. (of course the value increases)
Keep
asking them why:
Why
the pulse rate increases after physical activity?
Why
are we breathing faster than before?
Why
do we feel tired?
What
other changes do you feel / observe? (refer to sweating)
Why
are we sweating?
Why
do we feel thirsty?
What
happen if we drink too much?
Let
the students think by themselves and discuss with their friends.
After
15 minutes rest, they measure their pulse rate for the third time.
Now,
the value decreases. Why?
Explanations
Start
with the definition of homeostasis
Homeostasis
is the maintenance of the body system to keep our body in a balance condition,
for example the body temperature and water content.
When
we feel hot, we are sweating to cool down our body. Heat from body is released together
with the sweat.
When we are sweating, the water content inside our body decreases. Therefore, we feel thirsty because the body need us to replace the water lost by drinking more water.
When
we feel cold, we are shivering. More heat energy produced to keep our body
warm.
When
we drink more water, more urine will be produced to maintain water content
inside the body. Oppositely, when we drink less water, less urine produced.
During
physical activity, more oxygen needed. Heart will pump more blood and breathing
mechanism increases. That’s why pulse rate increases as well as the breathing
rate.
Group
Discussion
Students
will be bored if everything is explained by the teacher.
So,
let them explore more by themselves.
Students
are asked to discuss in group what are the systems involved in homeostasis.
After
the discussion, students present and explain the concept of homeostasis.
Students
are then asked to observe their surroundings.
Observe
what animals usually do (we have cats and dogs at our school)
Closure
Homeostasis
plays an important role in our daily life. The body temperature and water
content in our body must be maintained in an optimum level to keep our body in
a balance condition. Can you predict what will happen if our kidneys cannot
function properly? Will it affect homeostasis?
LIMITATIONS
For form 1 syllabus, homeostasis is
only focus on regulation of water content and body temperature. The conditions
discussed are including sweating, shivering, heartbeat rate and production of
urine. The two systems involve are endocrine system and urinary system.
