Students’ Alternative Conceptions of Thermoregulation and Methods for
Conceptual Change
Introduction
This paper presents the findings of two clinical interviews conducted with students from
different Year 11 Biology classes. The interviews were conducted to expose alternate
conceptions in regards to thermoregulation by ectotherms and endotherms.
After a brief introduction and explanation of the purpose of the interview, the students
were presented a series of questions (Appendix A). The VCE guidelines for this area of
study suggest that students, “should be able to explain and analyse the relationship
between environmental factors, and adaptations and distribution of living things”.
The questions were broken down into three categories to assess the level of student
understanding.
1. Terminology
2. Environmental, physiological and behavioural affects on thermoregulation
3. Complex conceptual understanding
The series of questions aimed at exploring the students’ knowledge and understanding of
the terminology, included questions relating to the terms ‘cold-blooded’, ‘warmblooded’, endothermic and ectothermic.
Results
Both Jill and Dave demonstrated a good understanding on the terms endotherm and
ectotherm and gave appropriate examples of animals in each group (mammals as
endotherms and reptiles as ectotherms). Both students used the terms ‘cold-blooded’ and
‘warm-blooded’ interchangeably with ectothermic and endothermic respectively.
‘Ectotherms like snakes and lizards get their temperature from the sun and rocks’. Dave
When probed for their ability to link thermoregulation to environmental factors,
physiological adaptations and behaviours, both students demonstrated some alternative
conceptions that were consistent with previous studies by Soyibo (1995), Barrass (1984),
and Westbrook and Marek (1992).
The students considered ectotherms cold-blooded because they cannot control changes to
body temperature, this does not recognise the influence of environmental factors or
behaviour of the organism.
‘Snakes are cold-blooded (be)cause they can’t make their own body heat’. Jill
‘… and ectothermic animals can’t produce their own heat, they get it from the
environment and that’s why they have a variable temperature.’ Dave
Soyibo (1995) links this alternative conception to incorrect interpretation of a particular
graph (Figure 1., Appendix A.). In confirmation, when presented with the graph, both
students concluded that it indicated that the snake could not change its body temperature
because the body temperature changes as the outside temperature changes.
To explore student ability to integrate and understand concepts of heat exchange and
physiological adaptations that are involved in thermoregulation, a modified version of a
scenario used in Simpson and Marek (1988), and Westbrook and Marek (1992) in similar
studies was utilised. The scenario was modified for conversion from empirical to metric
units and to add the observation of the person’s face turning red after exercise to test for
concept understanding of relaxing peripheral blood vessels and surface heat exchange.
Jill gave an impressive response with lots of detail including the role of body systems
such as the endocrine system and nervous system. All the body processes were explained
soundly including the role of peripheral blood vessels. Jill identified that metabolism
causes body heat but could not elaborate further.
Dave did not consider the appropriate factors influencing body temperature or attributed
causes to other factors. Similar results were found in a study by Westbrook and Marek
(1992).
‘Body temperature doesn’t change due to humans being endothermic’, and,
‘Circulation of blood and movement of organs cause body heat’. Dave
In addition, Dave did not link the exercise to internal body temperature and believed it
was only affecting the surface of the body. The function of sweating and peripheral blood
vessels was to cool the surface. While this alternate conception is not specifically noted
in the literature, studies by Kjærnsli, Angell, and Lie (2002), and Westbrook and Marek
(1992), report a number of common conceptions relating to perspiration and exercise.
Discussion
Dave and Jill’s science faculty were trialling a curriculum change where the Year 11
Biology commenced with VCE Unit 2 followed by Unit 1. The lack of knowledge of cell
metabolism may be explained, as Unit 1 largely relates to understanding cells.
Due to room availability at the school, the interviews were undertaken at some computer
desks in a busy hallway. This was not an ideal location and further interviews should be
undertaken in a more comfortable location for the students to concentrate.
In addition, interviewing techniques were a little rushed due to the inexperience and
nervousness of the interviewer. More time spent at the start of the interview developing
rapport with the student would be highly beneficial to encourage further response from
the student and develop interviewer confidence.
This study was informed by, and developed using similar approaches to, previous studies.
This was to enable comparative results and the concept evaluation statement was
validated by a panel of science educators. However, by doing so, the study was
effectively designed to uncover only previously identified alternate conceptions. Very
little new information was identified using this approach. Further studies should be
developed using different, innovative questions to gain a more complete understanding.
Lesson Plans
This study, in support of Soyibo (1995), identified that students commonly do not link the
organism and its processes to the environment in which it is situated. To get students
thinking about the importance of environmental factors, the case study in Lesson Plan 1.,
Appendix B. will generate student interest, make the relevance clear, and evoke curiosity.
The many different pertinent variables of the case study will generate lots of class
discussion. The class will be able to take ownership of the issue and generate the answers
by themselves. This is a student-centred approach that enables student participation and
allows analysis of students’ prior knowledge and conceptions.
By utilising interesting technology such as thermographic imagery, the desert lizard clip
will highlight different heat exchange (convection and conduction). It illustrates the role
of animal behaviour, that ectotherms are able to thermoregulate, and that demonstrates
that ectotherms are not necessarily ‘cold-blooded’ which are common alternative
conceptions.
The general technique of recording student answers/opinions on the board and facilitating
class discussion to shortlist/summarise to result in an agreed answer gives students a
sense of contribution, achievement and confidence. This technique is employed
throughout the lesson plans.
Where possible, students are asked to reflect on their own learning to reiterate concepts
and promote a metacognitive understanding. Assessment tools are used throughout the
three lessons and range from observing while circulating the class to more formal case
studies that are proven to assess conceptual understanding.
Lessons were developed to be as interactive and student-centred as possible. Having
students draw diagrams on the white-board gives shared responsibility, power and
ownership of the classroom. For example the human tolerance ranges and the
thermostat/negative feedback system diagrams from Lesson Plan 2., Appendix C and the
animal behaviour graph from Lesson Plan 3., Appendix D.
Use of challenges like ‘bonus points’ for finding an organism that is an ectotherm and a
homeotherm enables student motivation and also acts as a constant reinforcement of the
concept that the environment matters when concerning thermoregulation.
Giving interesting examples of endotherms that have a variable body temperature by
torpor or hibernation such as hummingbirds and some possums reinforces that the
metabolism is generating heat and if an animal lowers/decreases its’ metabolism it is not
generating as much heat (common alternative conception).
To facilitate conceptual change with terms cold-blooded and warm-blooded, students are
introduced to the terms to identify existing knowledge. For example, ‘reptiles are coldblooded because they can’t make body heat’. Scenarios are provided under which, the
students’ alternate concept fails or breaks down, they will logically see the flaws in their
thinking and are more likely to construct the more appropriate understanding.
The out of class learning activity of Lesson Plan 3. is to demonstrate that the real
environment is complex and small niches have variable temperatures. This enables
students to link behaviour to the real world and develops their investigative techniques.
References
Barrass, R. (1984). Some misconceptions and misunderstandings perpetuated by teachers
and textbooks of biology. Journal of Biological Education, 18(3), 201-206.
Campbell, N. A., Reece, J. B., & Mitchell, L. G. (1999). Biology (5th Ed.). Menlo Park,
CA: Benjamin/Cummings.
Kinnear, J., & Martin M. (2006). Physiological adaptations for survival. In Nature of
Biology: Book 1 (3rd ed.) (pp.297-340). Milton: John Wiley & Sons.
Kjærnsli, M., Angell, C., & Lie, S. (2002). Exploring population 2 students’ ideas about
science. In D. F. Robitaille & A. E. Beaton (Eds.), Secondary Analysis of the
TIMSS Data (pp. 127-144). New York: Kluwer Academic Publishers.
Simpson, W. D., & Marek, E., A. (1988). Understandings and misconceptions of biology
concepts held by students attending small high schools and students attending
large high schools. Journal of Research in Science Teaching, 25(5), 361-374.
Soyibo, S. (1995). A review of some sources of students’ misconceptions in biology.
Singapore Journal of Education, 15(2), 1-11.
Thermoregulation. (2010). In Wikipedia, The Free Encyclopedia. Retrieved from
http://en.wikipedia.org/w/index.php?title=Thermoregulation&oldid=365112913
Westbrook, S. L., & Marek, E. A. (1992). A cross-age study of student understanding of
the concept of homeostasis. Journal of Research in Science Teaching, 29(1), 5161.
Victorian Curriculum and Assessment Authority. (2010). VCE Unit 2 Biology Study
Design. Retrieved from
http://www.vcaa.vic.edu.au/vce/studies/biology/biologyindex.html
Appendix A. Interview Questions
Knowledge of terminology
1. What do you think of when you hear the terms “cold-blooded” and “warmblooded”?
2. Do you know the terms endothermic and ectothermic? Can you give examples for
each?
Environmental, physiological, and behavioural affects on thermoregulation
3. Will an ectothermic organism always have a variable body temperature?
4. What factors cause ectothermic body temperature?
5. Are there things that an ectothermic organism can do to make their body
temperature (relatively) stable if the environmental temperature is variable?
6. What if an ectothermic organism lived in an environment that had a constant
temperature like tropical rainforests or the water?
7. If an endotherm maintains a constant body temperature, the heat being lost must
equal the heat being gained. What are some types of heat source (gain)? What are
some types of heat loss?
8. How do endotherms create internal body temperature/heat.
9. What do you think Figure 1. is saying?
Figure 1.Extracted from Campbell, Reece, and Mitchell (1999).
Complex conceptual understanding (adapted from Simpson and Marek, 1988)
10. A person goes in for a physical fitness test. First, the doctor takes readings of a
person’s heart rate, breathing rate, and body temperature after the person has been
sitting in a chair for five minutes. The person’s breathing rate is 18 breaths per
minute. The heart rate is 60 beats per minute. The person’s body temperature is
37.0 degrees Celsius. The doctor then asks the person to run a distance of 400
metres. Just after this exercise, the heart rate, breathing rate, and body
temperature are again recorded. The breathing rate has increased to 40 breaths per
minute, the heart rate has increased to 115 beats per minute, and the body
temperature remained 37.0 degrees Celsius. Also the doctor notices that the
person’s face is red and they are now sweating. The person is told to sir in a chair
for fifteen minutes after which the heart rate and breathing rate have returned to
their first readings. After the test the person drinks water from a fountain to
satisfy a developing thirst.
In a paragraph list all bodily processes that changed or didn’t change because of the
exercise. Include an explanation why they changed or didn’t change.
Prompting questions for 10.
 Did body temperature change? Why?

Did heart rate/breathing rate change? Why?

Explain why subject got red in face.

Explain why subject got sweaty.

Explain why subject got thirsty.

What does exercise do to body temperature? Why/How?
Appendix B. Lesson 1.
Specialism Area: Biology
Main Topic: Homeostasis – Thermoregulation
Curriculum Links:
VCE Unit 2 Biology Study Design – Study Area 1, Organisms and
their environment. (Nature of Biology – Book 1: Chapter 10 Physiological Adaptations).
Learning Object/s for students: By the end of this session the students should
be able to identify and describe:

the types of heat exchange that can occur between an organism and its’
environment,

physiological adaptations that enable organisms to influence heat exchange
(gaining heat, reducing heat loss, or maximising heat loss).
Teaching objective: This session I will focus on evoking student curiosity,
provoking questions, and class discussion.
Procedure:
Introduction
Introduce the topic of thermoregulation with a case study. Present story of the
White-Plumed Honey-Eater. Hand around photographs of the bird being held
and measured. This is an incident happened when we were undertaking bird
tagging on the Mitchell grass plains in Queensland, it was a very hot day. We set
mist nets to trap the birds and caught a White-Plumed Honey Eater, which was a
rare catch for that environment. Everyone crowded around and wanted a hold
and photograph. Eventually the bird’s feathers started to look ruffled and it
started panting. A young student was holding it for a long time. Someone said
that the bird looked stressed and the girl released it into the sky.
The bird took off but then fell down dead mid flight. Possibly room for Monty
Python parrot sketch joke to lighten the mood.
Case Study
Write on the board: What killed the White-Plumed Honey-Eater?
While saying:
 Working in pairs,

Write down three things that may have influenced its’ demise.

What could have been done to prevent it? And

What was the bird trying to do to prevent it?
(Write questions on board)
5-10mins – circulate around room, see how students are going and answer
questions
Get each group to give a factor, put them on board. Discuss with class to get a
good list, may need to prompt/remind them of bits of the story.
 Hot day – air temperature

Crowding around – radiant heat from bodies

Holding – conductive heat from hands

Stress/Shock – Internal heat gain

Final flight – rapid muscle movement, increased body temperature too
much.

Bird was ruffled to expose skin to allow heat loss, feathers act like a coat –
trapping radiant heat.

Bird was panting – convection and radiant heat loss explain not
evaporative heat loss like dog panting
Summarise the types of heat transfer, write on board.
Get students to copy into books under appropriate heading.
Lizard Clip
Set up then play short clip from documentary: Namib Desert lizard that lifts feet
off ground to cool them. Highlights the difference between Conduction and
Convection nicely.
http://www.youtube.com/watch?v=1rkkKyYCxio
After clip ask (hands up):
What type of heat transfer was happening with the lizards’ foot on the ground?
What type when it lifted it off the ground?
Give students time to make additional notes in their books.
Humans
Working in pairs again: What happens when we get hot or cold? come up with a
list of 3 for each hot and cold. (write questions on board).
5-10 mins - circulate around room, see how students are going and answer
questions
Get answers from students, compile on the board, discuss then summarise.
Give students time to make additional notes in their books.
Go to interactive website that shows how peripheral heat is lost and shows
constriction and relaxation of surface capillaries to reinforce that mechanism of
managing heat loss.
http://www.biology.ualberta.ca/facilities/multimedia/uploads/zoology/counter%20current
.swf
Reflection
(Hands up) What did you learn today?
What did you find interesting? Do you want to know more about anything we
discussed today?
Can someone name a type of heat transfer? Can describe or give an example of
that?
Eg: Conduction – when the heat from the desert sand was going into lizard’s foot
Evaporation – when water evaporates off your skin it cools you – Sweating
Are you going to cuddle a bird next time you catch one?
What did the bird do to try to lose heat?
Follow-up activity
Next lesson talk about homeostasis and how organisms’ senses enable them to
maintain a constant internal. Before the next lesson – look up homeostasis and
write down what you think it means. Also, list the 5 main senses that humans
have. (bonus if you come up with a 6th one). I will be checking books next lesson.
Summary of Content/Activity:
Introduction: 5 mins
Case Study Activity: 20 mins
Lizard clip Activity: 10 mins
Human Physiological Adaptations: 10 mins
Reflection and Follow-up: 5 mins
Intro to Homeostasis (backup if things go quickly)
Appendix C. Lesson 2.
Specialism Area: Biology: Homeostasis – Thermoregulation
Curriculum Links: VCE Unit 2 Biology Study Design – Study Area 1,
Organisms and their environment. (Nature of Biology – Book 1: Chapter 10
Physiological Adaptations).
Learning Object/s for students: By the end of this session the students
should be able to:


describe homeostasis and why it is important, and,
identify the major body systems responsible for homeostasis and describe
the way human bodies detect and respond to temperature change.
Teaching objective: This session I will focus on the use of open ended questions
and use of clear instructions.
Procedure: Recap on last lesson. Handout case study (Appendix E. Assessment
Tool). To be collected afterwards so please put your name on it.
I will check on homework while you are working – Circulate to check off who
completed homework and be available for questions.
Homework – look up homeostasis and write down what you think it means. Also,
list the 5 main senses that humans have. (bonus if you come up with a 6th one).
Collect handout (make sure names are on them)
Go through handout with class.
 Did body temperature change? Why?

Did heart rate/breathing rate change? Why?

Explain why subject got red in face.

Explain why subject got sweaty.

Explain why subject got thirsty.

What does exercise do to body temperature? Why/How?
Homeostasis - Write on board
(Hands up) What did you find from your homework? What do you think it is?
Homeo or Homo? = Same, Stasis = state
It means same state or steady state.
Why do we care? What does it mean for us in relation to body temperature?
What about the bird from last lesson?
Is your internal temperature variable?
We have some pretty limited tolerance ranges
Get two students up to draw a core body temp graph on board (body temp on x
axis and a range of happiness (happy smiley face to sad maybe) on y axis).
Have a print out of a range of human body temps and the described associated
symptoms (Appendix F.).
Circulate room while two students up the front and get students to read the
normal symptoms for a particular body temp. Have the class decide on a
happiness factor (eg 42 °C would be unhappy) and have the students up the
front mark it on the chart. This will identify the narrow tolerance (happy) range
for human body temp.
Homeostasis is very important for cells, for your body to operate properly. Ask
about enzymes, if they do, go into it a bit more enzyme denaturing.
Ask questions that link physiological adaptations of last lesson to achieving
homeostasis.
How does the body know whether to cool down or heat up?
Talk about senses, what the students put for their homework, go around class.
Possibly have a joke with a 6th sense to promote a bit of interest - Kinesthetic
sense, provides the brain with information on the relative positions of the parts
of the body. At no time will the person lose awareness of where the hand
actually is, even though it is not being detected by any of the other senses. Have
students close their eyes and touch their nose for an example, then have them
close their eyes and touch their two fingers together – most will fail.
Get back on topic with the touch/tacile senses – talk about how they respond to a
stimulus like heat. Introduce the role of the Nervous and Endocrine (hormone)
System.
Negative feedback systems
Does anyone know how a thermostat works? (if they do help them draw a
diagram on board). If not draw one.
Talk about negative feedback and relate to the body system.
Students to copy diagram in books and make notes.
Nerves and Hormones
Using text book, write down the answers in your book (give page number):
 What are the major components of the nervous system?

How do nerves send messages?

How do endocrine glands get messages

How do endocrine glands send messages
(Write questions on board)
When you’re finished have a go at the activity sheet (Appendix G.). Cut and paste
the labels and definitions of what they do to match the body.
10 mins – circulate around room, see how students are going and answer
questions
Get answers from students, put them on board. Discuss with class to get agreed
answers
Reflection
(Hands up) What did you learn today?
What did you find interesting? Do you want to know more about anything we
discussed today?
Ask reflective questions. Describe the full process of a person reacting to hot day
– from sense to sweat
Follow-up activity
Next lesson talk about how different organisms have different ways producing
body temperature and look at behaviour (like the lizard lifting his foot) and
thermoregulation. Before the next lesson – look up Ectotherm, Endotherm,
Poikilotherm and Homeotherm. Describe the differences and give an example
animal for each. Bonus points if you come up with an animal that is both an
Ectotherm and a Homeotherm. I will be checking books next lesson.
Summary of Content/Activity:
Introduction: 15 mins
Homeostasis: 10 mins
Senses and Negative Feedback Systems: 10 mins
Nerves and Hormones: 10 mins
Reflection and Follow-up: 5 mins
Endotherm and Ectotherm Intro (backup if things go quickly)
Appendix D. Lesson 3.
Specialism Area: Biology: Homeostasis – Thermoregulation
Curriculum Links:
VCE Unit 2 Biology Study Design – Study Area 1, Organisms and
their environment. (Nature of Biology – Book 1: Chapter 10 Physiological Adaptations).
Learning Object/s for students: By the end of this session the students should
be able to:


Compare the difference between between the terms ectotherm, endotherm,
poikilotherm, homeotherm and give examples organisms for each.
Investigate and relate organisms behaviour to environmental factors.
Teaching objective: This session I will focus on student participation and
investigation, and use of clear instructions.
Procedure:
Introduction
Recap on last lesson – handout marked assessment, check homework.
(Hands up) How does your body know that it is getting to hot or cold?
What does your body do about it?
Which gland connects the nervous system to the endocrine system?
Homework – look up Ectotherm, Endotherm, Poikilotherm and Homeotherm.
Describe the differences and give an example animal for each. Bonus points if
you come up with an animal that is both an Ectotherm and a Homeotherm.
Terminology
Get answers from students, put them on board. Discuss with class to get agreed
answers
Go through a number of examples:
Eg Fish are ectotherms and homeotherms because the water is constant
There are even endotherms that are poikilotherms!
Give example of the hummingbird – needs so much energy (80 wing
beats/second) that it has to hibernate everytime it sleeps. Talk about topor and
hibernation in relation to metabolism and body heat. As the metabolism drops
so does the body temp. During the day 40 C, during the night drops to 4 C (if the
environment is that cold). Mention that there is a possum in Victoria that does a
similar thing.
Write on the board “Cold-Blooded” and “Warm-Blooded”- Ask students to define
them and give example animals. The students will give reptiles for cold blooded
and either mammal or bird for warm blooded.
Ask about the temperature of the desert lizard – hotter than us – cold blooded?
Ask about hummingbird or possum or any hibernating mammal – warm
blooded?
Are these terms as good as the others for describing animals – No!
Animals like reptiles get their body temperature from the environment.
How do they maintain a relatively stable body temperature?
Behaviour!
Behaviour Activity – Give detailed instructions to students
Ideal materials – a number of rubber lizards and a laser reading, digital
thermometer. Failing that, any objects that you can stick an alcohol
thermometer in.
Go outside and place objects in different positions around the schoolyard. On or
in logs, in the shade, in direct sun, under leaves, a variety of niches.
Go back inside
Have two volunteers draw a graph on the board with time of day over a 48hr
period as the x axis and temperature as the y axis. Draw a line that fluctuates
from day and night. Mark this as air temperature.
Get volunteers to come up with different animals and get them to plot how the
animal’s temperature would change (if any) over the time period. Get them to
explain each line.
Let students make notes or copy a version of the graph.
For example a snake would look like this:
(Figure extracted from Kinnear and Martin, 2006)
Go back outside and get students to measure the temperature of their object,
record it and come back inside.
Compile list of niches and the corresponding temperature of the object on board.
Students to transcribe into books.
Get students to draw conclusions on behaviour and environmental temperature
variations temporally and spatially.
Reflection
(Hands up) What did you learn today?
What did you find interesting? Do you want to know more about anything we
discussed today?
Ask reflective questions. Will ectotherms always have variably body
temperatures (poikilothermic)? Why? What about constant environments like
the ocean? Can ectotherms do anything to change their body temperature?
Examples?
Follow-up activity/Assessment tool.
Give students handout for homework (Appendix H.). I will be collecting and
marking handouts next lesson.
Summary of Content/Activity:
Introduction: 5 mins
Terminology: 10 mins
Behaviour Activity: 30 mins
Reflection: 5 mins
Appendix E. Case Study Handout (Assessment Tool)
A person goes in for a physical fitness test. First, the doctor takes readings of a
person’s heart rate, breathing rate, and body temperature after the person has been
sitting in a chair for five minutes. The person’s breathing rate is 18 breaths per
minute. The heart rate is 60 beats per minute. The person’s body temperature is 37.0
degrees Celsius. The doctor then asks the person to run a distance of 400 metres.
Just after this exercise, the heart rate, breathing rate, and body temperature are again
recorded. The breathing rate has increased to 40 breaths per minute, the heart rate has
increased to 115 beats per minute, and the body temperature remained 37.0 degrees
Celsius. Also the doctor notices that the person’s face is red and they are now
sweating. The person is told to sir in a chair for fifteen minutes after which the heart
rate and breathing rate have returned to their first readings. After the test the person
drinks water from a fountain to satisfy a developing thirst.
In a paragraph list all bodily processes that changed or didn’t change because of the
exercise. Include an explanation why they changed or didn’t change.
Appendix F. Human Temperature and Symptoms (source Wikipedia)
Hot








37 °C - Normal body temperature (which varies between about 36.12–37.5 °C)
38 °C - Sweating, feeling very uncomfortable, slightly hungry.
39 °C - Severe sweating, flushed and very red. Fast heart rate and breathlessness.
There may be exhaustion accompanying this. Children and people with epilepsy
may be very likely to get convulsions at this point.
40 °C - Fainting, dehydration, weakness, vomiting, headache and dizziness may
occur as well as profuse sweating. Starts to be life- threatening.
41 °C - (Medical emergency) - Fainting, vomiting, severe headache, dizziness,
confusion, hallucinations, delirium and drowsiness can occur. There may also be
palpitations and breathlessness.
42 °C - Subject may turn pale or remain flushed and red. They may become
comatose, be in severe delirium, vomiting, and convulsions can occur. Blood
pressure may be high or low and heart rate will be very fast.
43 °C - Normally death, or there may be serious brain damage, continuous
convulsions and shock. Cardio-respiratory collapse will likely occur.
44 °C or more - Almost certainly death will occur; however, patients have been
known to survive up to 46.5 °C.
Cold









37 °C - Normal body temperature (which varies between about 36–37.5 °C)
36 °C - Mild to moderate shivering (body temperature may drop this low during
sleep). May be a normal body temperature.
35 °C - (Hypothermia) is less than 35 °C - Intense shivering, numbness and
bluish/grayness of the skin. There is the possibility of heart irritability.
34 °C - Severe shivering, loss of movement of fingers, blueness and confusion.
Some behavioural changes may take place.
33 °C - Moderate to severe confusion, sleepiness, depressed reflexes, progressive
loss of shivering, slow heart beat, shallow breathing. Shivering may stop. Subject
may be unresponsive to certain stimuli.
32 °C - (Medical emergency) Hallucinations, delirium, complete confusion,
extreme sleepiness that is progressively becoming comatose. Shivering is absent
(subject may even think they are hot). Reflex may be absent or very slight.
31 °C - Comatose, very rarely conscious. No or slight reflexes. Very shallow
breathing and slow heart rate. Possibility of serious heart rhythm problems.
28 °C - Severe heart rhythm disturbances are likely and breathing may stop at any
time. Patient may appear to be dead.
24–26 °C or less - Death usually occurs due to irregular heart beat or respiratory
arrest; however, a woman named Anna Bågenholm was recorded to have survived
with body temperatures as low as 13.7 °C (56.7 °F).
Appendix G. Endocrine glands Activity (assume labels are removed from the picture)
Cut out these labels and glue onto the picture of the human endocrine glands
Hypothalamus
Testes
Pituitary Gland
Pancreas
Adrenal Gland
Parathyroid Gland
Thyroid Gland
Ovary
Helps to maintain homeostatis by coordinating the
endocrine and nervous systems, also regulates the
pituitary gland
Releases several hormones including adrenaline
(increases heart rate & blood pressure)
Releases insulin (allows cells to take glucose from the
blood) & glucagon (controls release of glucose from the
liver)
Releases oestrogen and progesterone (controls
development of breasts & reproductive system,
regulates menstual cycle and pregnancy)
Releases parathormone (regulates
calcium level in blood; controls
development)
Releases testosterone (controls
development of male reproductive
system & changes during puberty
Releases thyroxine (regulates cell
growth)
Stores and releases two hormones
produced by the hypothalamus, also
produces many hormones that
regulate diverse body functions
Appendix H. Homework/Assessment Tool
1. Describe the relationships that the above figure is showing.
2. Would this be a good representation of the ectotherm’s body temperature in its
natural environment?
3. Why/Why not?
4. Describe the factors that influence an ectotherm’s body temperature.