Human Body Systems B
SARS-CoV-2 “Shelter-in-Place” Assignment #8 (May 18th – May 22nd)
Instructions:
Digital assignments can be turned in via Microsoft Teams, Remind or e-mail. You can upload
or share your MS Word or Google docs document, digital pictures, or scans. Paper copies of
assignments can also be manually turned in by bus route or dropped off at the main office.
IF YOU CAN TURN IT IN DIGITALLY DIRECTLY TO ME, DO SO. KEEP pages 1 through 11 of this week’s packet. You only need to turn in pages 12 through 18.
I will provide feedback to you and use a “pass” or “no credit” grade for the week.
It is always important to focus on your learning and not “just get the work done”. You will be
held responsible to know previous material on future packets – I intentionally build upon
previous learning!
Weekly Zoom meetings will be held Thursday afternoons at 2PM.
https://us04web.zoom.us/j/2312611708
I am here to help! Arrange an online meeting or ask questions via e-mail or Remind.
Recommended Weekly Schedule:
Monday – 3.1.1: READ FOR UNDERSTANDING: Resources for Life
DO: Activity 3.1.1, pages 12-13
Tuesday – 3.1.2: READ FOR UNDERSTANDING: The Rule of Threes
DO Activity 3.1.2, page 14
Wednesday - 3.2.1: READ FOR UNDERSTANDING: What Are Action Molecules?
NO ASSIGNMENT
Thursday - DO Activity 3.2.1, page 15
3.2.2: READ FOR UNDERSTANING: Digestive System Design
Friday - How you doin?
DO: Review Crossword, pages 17&18
Page 2 of 18
Activity 3.1.1: Resources for Life
Introduction
Each year, hundreds of athletes pull on their running shoes and set out on a 160- mile, seven-
day race across the Sahara Desert. The Marathon des Sables, or the Marathon of the Sands,
is one of the most grueling endurance events on the planet. With the potential of daytime
temperatures over 120°F, runners are bombarded with superheated air flowing over their skin
and into their lungs. Competitors carry limited supplies with them in backpacks and water is
provided only at designated checkpoints. These endurance athletes have trained physically
and prepared mentally, but will their bodies have the power to propel them to the finish?
In 1994, in the fourth leg of the marathon, endurance runner Mauro Prosperi lost sight of the
trail. A sandstorm covered the course markers, leaving Mauro alone to compete in a different
race - the race to stay alive. For the next nine days, on extremely limited food and water, Mauro
made his way across the desert. His incredible story baffled doctors and physiologists. How
could a man possibly live in these conditions for such a long period of time? Mauro’s body,
however, provided more than enough evidence to corroborate his story. When he was found,
he had lost 33 pounds, his body required over 16 liters of water to replace his water loss and
his kidneys and his digestive system were almost completely shut down. Miraculously, he was
still alive. Faced with immeasurable amounts of stress, the amazing human machine became
even more amazing. Adaptations of the body and of the mind helped this man push past the
thresholds of human endurance and show the power the body has to stretch vital resources to
their absolute limit.
Stories of human survival in extreme environments highlight the body’s amazing ability to
adapt and to fight to maintain homeostasis1. Various body systems create and distribute fuels
and provide power to human function. The resources we input and circulate around our body
fuel every major process that keeps us alive. If these resources become scarce, the body will
try to adjust. If one of these supplies reaches a critical low, the body will shut down.
In this introductory activity, you will discuss the resources that power the human machine. You
will examine the key resources your body needs to survive and brainstorm the human body
systems that supply power and energy and remove harmful waste.
Do assignment on pages 12-13 1 Homeostasis: The keeping of relatively stable body related conditions (as body temperature or the pH of
blood) in higher animals under changing environmental conditions.
Page 3 of 18
Activity 3.1.2: The Rule of Threes
Introduction
With each breath, we take in oxygen that feeds our cells and fuels the production of energy.
Water nourishes our tissues and helps regulate the level of chemicals in the body. The
carbohydrates, proteins and fats that we ingest in food supply energy, as well as build
materials the body uses for growth and maintenance. Each of these resources is vital to human
survival. But how long can the body last when one of these resources reaches a critical low?
In Activity 3.1.1, you read the incredible story of Mauro Prosperi. Somehow, he beat the odds
and managed to survive under unimaginable conditions. The human body has the ability to
adapt to internal and external changes and to conserve valuable resources. In this activity, you
will continue your exploration of fuel and power in the body and debate the validity of a survival
rule: The Rule of Threes. You will examine how factors unique to the person or the environment
may help that person survive in the absence of vital resources or, sadly, push him/her closer
to the edge.
Many survival guidebooks reference the Rule of Threes, rough estimates for how long a person
can last without key resources. This rule states that a human can live:
➢ 3 minutes without air
➢ 3 days without water
➢ 3 weeks without food
Do Assignment on page 14
Page 5 of 18
3.2.1: What Are Action Molecules?
Introduction
Chemical reactions are essential for life and occur in all living tissues. Regulating homeostasis
depends upon properly maintaining these reactions. Enzymes1 are an important component
for that maintenance. Enzymes are a type of protein called catalysts2. A catalyst facilitates or
helps a reaction to occur more readily by reducing the energy required for the reaction to occur.
The catalyst is not part of the actual reaction, does not change the chemical reaction, and is
not permanently altered by reaction. It does however facilitate the reaction and can be used
over and over again.
Most chemical reactions in the body are dependent upon enzymes. Enzymes are highly specific
and work on only one substance called its substrate3. In this activity, you will learn why
enzymes are specific for a particular substrate.
Information
1Enzymes- A protein serving as a catalyst, a chemical agent that changes the rate of reaction without being
consumed by the reaction. 2Catalyst- A substance that enables a chemical reaction to proceed under different conditions (as at a
lower temperature) than otherwise possible. 3Substrate- A substance acted upon by an enzyme.
Page 10 of 18
For those with internet access:
A video showing the 3D model project we would have made in class: (1 minute)
https://www.youtube.com/watch?v=9srJT79H7oc
Amoeba Sisters video on Action Molecules and Pac-Man: (5 minutes)
https://www.youtube.com/watch?v=qgVFkRn8f10
TOMORROW: Do Activity 3.2.1: What Are Action Molecules? On page 15
3.2.2 Digestive System Design
Introduction:
During his or her lifetime, the average person eats at least 20 tons of food. Meats, vegetables
or sweets—whatever your diet, that’s 40,000 pounds! Our digestive system works to turn this
enormous amount of food into substances that the body can use for energy and for growth and
repair. But what actually happens to these foods once they enter our bodies? How does the
body process each tasty bite and harness the power locked in the food?
The digestive system works like an assembly line in reverse. Carbohydrates, fats, and proteins
are progressively broken down into smaller molecules that can be used by the body. This
system extracts needed nutrients and gets rid of any unnecessary wastes. Structurally, the
digestive system consists of a long tube, the gastrointestinal (GI) tract, that serves as the direct
pathway for what you eat and excrete. Along the way, various accessory organs help with the
mechanical breakdown and the chemical digestion of food.
Mechanical digestion involves physically mashing or tearing the bites of food we put in our
mouths. We normally think of mechanical digestion occurring in the mouth, but there are other
features of your GI tract that also help mash up your food. As what you consume is being
smashed, chemical digestion also begins. Enzymes break fats, carbohydrates, and proteins
into their building blocks so they can be used by the body. Once these molecules are broken
down, they become the raw material for the production of the body’s energy currency,
adenosine triphosphate (ATP).
Page 12 of 18
Activity 3.1.1: Resources for Life
POWERING THE HUMAN BODY
Resources
Functions
Body Systems
Involved
Environmental
Factors
Personal/Human
Factors
1. Label the top of each column with one of the three main resources that are needed for
human life. Which solids, liquids and gases provide power to the human machine?
2. Brainstorm the functions of each resource. Think about how what you drink, eat or
breathe in affects body function. List your ideas in the appropriate space on the chart.
3. Brainstorm the human body systems that help create, process or distribute each
resource. List your answers on the “Body Systems Involved” row of the chart. Write one
sentence or phrase that describes how this system is involved with the resource below.
a. Resource #1-
b. Resource #2-
c. Resource #3-
Page 13 of 18
4. Rank the resources you have discussed in order of importance for the body. Ranking
#1 goes to the fuel that is most critical to your survival. Ranking #3 goes to the
resource you can go the longest without re-fueling. Add your rankings to the chart by
writing the number next to the name of the fuel and circle this number.
5. Brainstorm how long you think the body could go without each resource. What is the
“time to empty” for each fuel? Is it minutes? Hours? Days? Weeks? Years?
a. Resource #1-
b. Resource #2-
c. Resource #3-
Conclusion Questions:
1. In one sentence for each resource - water, food and oxygen – explain how this resource
helps provide power to the human body.
a. Water-
b. Food-
c. Oxygen-
2. What factors do you think influence how long your body can last without food, water or
oxygen?
Page 14 of 18
Activity 3.1.2: The Rule of Threes
1. Examine how the Rule of Threes compares to the estimates you came up with in Activity
3.1.1. Why might these rules may not apply to every person in every environmental
situation?
2. Brainstorm factors in the environment that may speed up or slow down this “time to
empty.”
a. Add these factors to the chart from Activity 3.1.1. (page 12)
b. Think back to the story of Mauro Prosperi. How did the high temperature of the
desert impact his body’s key resources?
3. Brainstorm factors unique to the individual that may speed up or slow down these
estimates.
a. Add these factors to the chart on page 12.
b. Mauro was 39 years old. Do you think he would have lasted as long as he did if
he were in his 60s? Why or Why not?
4. Compose a “disclaimer” to go under the rule. What would a sports enthusiast or a
traveler need to know about the factors that can affect how long the body can last in an
energy crisis?
5. Visit the Discovery Channel – Human Body: Pushing the Limits website at
http://dsc.discovery.com/tv/human-body/explorer/explorer.html
a. Click the bottom tab that says, “Strength.”
b. Choose video number “3” on the right side of the screen and watch the clip
about managing your fuel reserves.
Page 15 of 18
Activity 3.2.1: What Are Action Molecules?
In your own words, define the following:
● Enzyme:
● Substrate:
In your own words, discuss the following:
● Importance of Enzymes:
● How enzymes are named:
● Where enzymes are made:
● Lock and key model:
● Induced fit model
● Active sites
3.1/3.2 Review Crossword
Human Body Systems B
ACROSS
4 _____ intestine - absorbs nutrients into the bloodstream 4. ________________________
5 The "Rule" of _________ - a thumb rule for how long humans can live 5. ________________________
without key resources
10 ________ intestine - reabsorbs water and produces feces 10. _______________________
11 the air is made of 20% __________. 11. _______________________
13 area of an enzyme where substrate binds and undergoes a chemical reaction 13. _______________________
15 a quick energy source 15. _______________________
18 increases the rate of a chemical reaction 18. _______________________
21 a substance acted on by an enzyme 21. _______________________
23 the body's energy "currency" 23. _______________________
DOWN
1 Keeping stable body conditions under changing conditions 1. ________________________
2 small molecules that help enzymes to catalyze a reaction 2. ________________________
3 the digestive system breaks down food and water for absorption into the __________. 3. ________________________
6 proteins that help complex reactions 6. ________________________
7 glands that secrete materials to lubricate and break down food 7. ________________________
8 model of enzyme action where the correctly sized substrate fits into the active 8. ________________________
site of the enzyme
9 build and repair body tissues 9. ________________________
12 model of enzyme action where the active site is altered to fit the substrate 12. _______________________
14 a person can live 3 weeks without ____. 14. _______________________
16 endurance runner Mauro _________. 16. _______________________
17 a person can live 3 days without _____. 17. _______________________
19 long term energy source/ makes up much of the brain. 19. _______________________
20 enzymes are named by adding the suffix "___". 20. _______________________
22 a human can live 3 minutes without ___. 22. _______________________