Sponge: Set up Cornell Notes on pg. 47

Topic: 6.2 Regulation of Body Temperature

Essential Question:

1. Why is regulation of body temperature so important?

2.1 Atoms, Ions, and Molecules

1. Why is regulation of body temperature so important?

6.2 Regulation of Body Temperature

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Regulation of Body Temperature

• Even slight shifts can disrupt the rates of metabolic reactions

• Deeper body parts should be approx 98.6 degrees

• Amount of heat loss should = amount of heat produced

• Skin plays a key role

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• Active cells are major heat producers• Skeletal muscle cells• Cardiac muscle cells

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When body temperature rises….

• Nerve impulses stimulate structures in the skin and organs to release heat• Blood carries heat away• Warm blood reaches the brain and signals walls of

blood vessels to relax• Deeper blood vessels contract- leading blood to the

surface- skin reddens• Heat escapes to outside

Pg. 8 in INB

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When body temperature drops…

• Muscles in the walls of dermal blood vessels are stimulated to contract or become constricted

• Decreases the flow of heat-carrying blood through skin• Leads to color loss• Sweat glands remain inactive• Muscle cells in the skeletal muscle contract

rhythmically= shiver

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Radiation: The primary means of body heat loss

• infrared heat rays escape from warmer surfaces to cooler surroundings

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• Conduction: Heat moves from the body directly into the molecules of cooler objects in contact with its surface• Ex: heat moves into the seat of a chair • Continues as long as the seat is cooler than the body

touching it

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• Convection: Heat lost to air molecules that contact the body• Air becomes heated• Warm air moves away from body• Replaced by cooler air

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• Evaporation: When body temperature rises, sweat gland release sweat• As sweat dries/evaporates it carries heat away from the

surface

Sponge: Set up Cornell Notes on pg. 49

Topic: 6.2 Regulation of Body Temperature Cont.

Essential Question:

1. Please complete the Hyperthermia/Hypothermia prompt on a separate piece of paper by Mon Nov 4th.

2.1 Atoms, Ions, and Molecules6.2 Regulation of Body Temperature

Cont’

1. Please complete the Hyperthermia/Hypothermia prompt on a separate piece of paper by Monday Nov 4th.

Uncontrolled Temperature Regulation

Hyperthermia Hypothermia

Pg. 49

Based on what we already know about homeostasis, and how the body regulates

temperature, why is 110 degrees of “dry heat” more bearable than 90 degrees in humidity?

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• In dry heat, sweat will evaporate, cooling the body

• In humidity, sweat will NOT evaporate, leaving the person, hot, wet, and uncomfortable- could lead to hyperthermia

Anywhere on pg. 46Discussion Question:

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Hypothesize with your table:

• What is HYPERthermia?

• What is HYPOthermia?

Can you come up with an example of each?

Hint: Remember we are talking about how skin helps regulate body temperature.

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HYPERthermia HYPOthermia

Can we think of any creative ways to remember that HYPERthermia involves a dramatic rise in body temperature and HYPOthermia involves a dramatic drop in body temperature?

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• Hyperthermia: When body temperature rises too high• May occur if the temperature outside is hotter than

body temperature• May gain heat from surroundings and become

hotter• Can lead to fatigue, dizziness, heat exhaustion,

headaches, muscle cramps, nausea, or even death

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Hyperthermia to treat Cancer• Long needles are put directly into the tumor• Heat is directed into the tumor• Used along with radiation and/or

chemotherapy

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• ABC News Clip: 8 Children Left in Hot Cars in August (2012)

• Read NBC News “Deaths in Hot Cars Claim 8 Children so far this Spring”

• As a table, answer your assigned question. Everyone must be ready to share.

Hyperthermia in the News:

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1. How/When do most of the deaths occur?

2. What did ALL the children left in the cars have in common?

3. How long does it take for the temperature in a car to rise 20 degrees? 34 degrees? How does this explain how it is NEVER ok to leave a child in a car, no matter what the temperature outside is?

4. Why is a child (or an older person) more at risk of hyperthermia? Approximately how long before a child is in danger of dying?

5. What caused the increase in DEATHS due to children being left in cars since the early 1990s?

6. What were some of the ways to remind yourself to check the backseat?

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• Hypothermia: body temperature drops to a dangerous level• Caused by prolonged exposure to cold• May cause mental confusion, loss of reflexes, loss of

consciousness

• If body core drops just a few degrees, can lead to death

• However, the arms and legs can withstand drops of 20-30 degrees

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Death by Hypothermia Video

Which is Which?

Use your whiteboard to tell me…HYPO or HYPERthermia????

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Using the Homeostatic response sheet on Pg. 8…

•Task: Write a two-three paragraph journal entry on either hyperthermia OR hypothermia.

•Pretend you are someone suffering from hypothermia or hyperthermia. Please write two-three paragraphs describing your circumstances and the effects hyperthermia or hypothermia is having on your body. Make sure to include these details:

• Where are you?

• What are the circumstances that led you to this fate? (Backstory)

• Explain in detail the physical effects that you are experiencing.

•Please write this on notebook paper/journal paper to make it more authentic (if you were stranded in the desert you wouldn’t have a computer!)

•Due: Monday Nov 4th30