Name:

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Unit 3: Cellular Processes: Homeostasis Students will be able to:

3.1 Understand that homeostasis is the ability to maintain a constant internal environment despite changes within the external environment. The human body accomplishes this by using feedback mechanisms to stabilize systems and keep them within certain parameters.

Describe the general components of a feedback mechanisms and explain how they work

Explain how several body systems work together to maintain homeostasis

o Ex Cardiovascular and respiratory systems work together for cell respiration

3.2 Understand the body uses and produces four types of macromolecules in order to obtain the energy and create the structures to carry out basic life functions.

Use the structure and unique properties of carbon to explain why carbon is the basis of all organic molecules.

Be able to describe the function and building blocks of macromolecules and give examples of each. (elements, building blocks, function, example)

Be able to describe how monomers bond to become polymers. (Dehydration synthesis and hydolysis)

Describe the biomolecules used within the body and explain:

o How they are used by the body to maintain homeostasis

o Where they are found in our food

o The consequences of having too much or too little within our bodies

Keywords:

Homeostasis

Feedback Inhibition

Epithelial Tissue

Connective Tissue

Nervous Tissue

Muscle Tissue

Organic Compounds

Monomer

Polymer

Dehydration

Synthesis

Hydrolysis

Saccharide

Saturated fats

Unsaturated fats

Hydrophobic

Nucleotide

Adenosine

Triphosphate

Amino Acids

Catalyst

Substrate

Active Site

Activation Energy

Cofactor/Coenzyme

Cellular Processes: Homeostasis and Macromolecules

Date Topic

10/1 Introduction to Homeostasis Quick Lab and Notes

10/2 Body Systems Activity

10/3 Body Systems Activity

10/4 The Amazing Human Body-Survive Video

10/5 Introduction to Organic Molecules Notes and Organic Molecules Stations Lab

10/8 Organic Molecules Stations Lab

10/9 Macromolecules Lab

10/10 Dehydration Synthesis and Hydrolysis Model

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10/11 Enzyme Notes and Reading

10/12 Enzyme Manipulatives

10/15 Enzyme Manipulatives

10/16 Unit Review

10/17 Unit Multiple Choice Test

10/1/18

Objective: Students will be able to describe how the body maintains homeostasis: a constant internal

environment, despite changes within the external environment.

Warm-Up:

1. What are two things that I want you to know by the end of this unit?

2. When is your unit test?

3.1 Homeostasis

Introduction to Homeostasis: Quick Lab Directions: You will receive a thermometer and two beakers of water: one will warm water, and one will cold water. Develop a method to put water in a third beaker and keep it within one degree of 35̊ C for a period of 10 minutes. Method: In the space below, explain what you did for this activity. How did you keep the water at 35̊ C? Questions:

1. What were the challenges in trying to keep the temperature the same for a given period of time?

2. Compare this experiment with what you think happens to your own body during temperature regulation?

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Homeostasis

What is homeostasis?

Some things are easy to observe. When you run or swim or even write the answer to a test question,

you can see your body at work. But behind the scenes, your body’s systems are working constantly to

do something that is difficult to see and that few people appreciate-maintaning a controlled, stable

envionrnment. This stable enviornment is called homeostasis, which means “similar standing.”

Homeostasis describes the relatively constant internal physical and chemical conditions that

organisms maintain despite changes in internal and external enviornments. Homeostatsis amy not be

obvious, but for a living organism, it’s literally a matter of life or death.

Feedback Inhibition If you’ve ever watched someone driving a car down a relatively straight road, you

may have noticed how the person constantly moves the wheel left or right, adjusting direction to keep

the vehicle in the middle of the lane. In a certain sense, that’s how the systems of the body work, too,

keeping internal conditions within a certain range, and never allowing them to go too far to one side or

the other.

A Nonliving Example One way to understand homeostasis is to look at a nonliving system that

automatically keeps conditions within a certain range like a home heating system. In most homes, heat

is supplied by a furnace that burns oil or natural gas. When the

temperature within the house drops below a set point, a

thermostat sensor switches the furnace on. Heat produced by

the furnace warms the house. When the temperature rises

above a set point, the thermostat switches the furnace off,

keeping the temperature within a narrow range.

A system like this is said to be controlled by feedback

inhibition. Feedback inhibition, or negative feedback, is the

process in which a stimulus produces a response that opposes the

original stimulus. Figure 30-3 summarizes the feedback inhibition

process in a home heating system. When the furnace is switched

on, it produces a product (heat) that changes the environment of

the house (by raising the air temperature). This environmental

change then “feeds back” to “Inhibit” the operation of the furnace. In other words, heat from the

furnace eventually raises the temperature high enough to trigger a feedback signal that switches the

furnace off. Systems controlled by feedback inhibition are generally very stable.

A Living Example Could biological systems achieve homeostasis through feedback inhibition?

Absolutely. All that is needed is a system that regulates some aspect of the cellular environment and

that can respond to feedback from its own activities by switching on or off as needed. Such mechanisms

are very common, not only in the human body, but in all forms of life.

One example is the maintenance of body temperature. The body regulates temperature by a

mechanism that is remarkably similar to that of a home heating system. You can follow body

temperature regulation in Figure 30-4. A part of the brain called the hypothalamus produces chemicals

that signal cells throughout the body to speed up their activities. Heat produced by this increase in

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activity, especially cellular respiration, causes a gradual rise in body temperature, which is detected by

nerve cells in the hypothalamus.

Have you ever been so cold that you began to shiver? If your body temperature drops well

below its normal range, the hypothalamus releases chemicals that signal muscles just below the surface

of the skin to contract involuntarily-to “shiver”. These muscle contractions release heat, which helps the

body temperature to rise toward the normal range.

If body temperature rises too far above 37C, the hypothalamus slows down cellular activities to

reduce heat production. This is one of the reasons you may feel tired and sluggish on a hot day. The

body also responds to high temperatures by production sweat, which helps to cool the body surface by

evaporation.

Do you think that feelings of hunger and fullness are an example of feedback inhibition? Explain.

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Types of Body Tissues

1. Fill in the blanks:

Cells _____________ Organs ________________ Organism

2. Compare the characteristics of two types of tissues. Identify the parts of the body that contain

these types of tissues.

10/2/18

Objective: Students will be able to describe how the body uses feedback mechanisms to maintain a

stable internal environment despite changes within the external environment.

Warm-Up:

1. Name as many body systems that you can think of.

2. Match the system with one of the following functions: protection, connectivity, reproduction,

structure.

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10/3/18

Objective: Students will be able to describe how the body uses feedback mechanisms to maintain a

stable internal environment despite changes within the external environment.

Warm-Up: None

10/4/18

Objective: Students will be able to describe how the body uses feedback mechanisms to maintain a

stable internal environment despite changes within the external environment.

Warm-Up:

1. Describe how the digestive system and the circulatory system work together to help the body

maintain homeostasis.

2. Describe how the respiratory system and the muscular system work together to maintain

homeostasis.

Vocabulary Builder: Freyer Model Jig-Saw Vocab

10/5/18

Objective: Students will be able to describe how the body uses and produces the four types of

macromolecules in order to obtain the energy and create the structures to carry out basic life functions.

Warm-Up: Feedback loops can also model Earth’s systems, too! Use the following feedback loop to

answer the questions.

1. Is the feedback loop positive or negative?

2. Can a cycle like this be changed once it starts?

3. What changes could you make to alter this feedback loop?

4. Why are feedback loops a way to see what direction our planet may be heading and how to

prevent harmful changes?

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3.2 Introduction to Organic Molecules

Organic Compounds: Carbon

What is an Organic Compound?

o A group of molecules that contain .

o Carbon forms the key components of all life on Earth. Carbon can have up to

because of its structure.

Why study organic compounds?

o living things are made of organic compounds!

The Recipe

What else makes up the recipe for life? All types of organic compounds contain ,

but they may also contain:

o , phosphorous, , nitrogen, and hydrogen

o Along with hydrogen, carbon bonds with these elements to form organic compounds.

Four Types

There are four major categories of organic molecules that are found in all living things:

o

o

o

o

These are large molecules known as .

Monomer and Polymers

Each of the four types of macromolecules are made of smaller subunits called monomers.

o Mono = one A is a single unit of a structure

o Poly = many A is a larger structure made up of monomers.

o Analogy: a brick house is the polymer. What are the monomers (Building blocks) of the

house?

Ways to form polymers

o : removes water to join monomers to form a

polymer.

o It’s a chemical reaction: Monomer + Monomer Polymer + H2O

Ways to break apart polymers:

o : breaks the bonds in a polymer by adding water

to create monomers.

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o It’s also a chemical reaction: Polymer + H2O Monomer + Monomer

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10/8/18

Objective: Students will be able to describe how the body uses and produces the four types of

macromolecules in order to obtain the energy and create the structures to carry out basic life functions.

Warm-Up:

1. Why is carbon the best element to build living organisms?

2. Create an analogy for a monomer and a polymer. (Hint: think about the brick house)

10/9/18

Objective: Students will discover what macromolecules different foods contain and how these foods

give us energy to maintain homeostasis.

Warm-Up:

1. What is the difference between structural proteins and functional proteins?

2. Of the three macromolecules found in foods, which do you think is the most prevalent in our

bodies?

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10/10/18

Objective: Students will be able to model how polymers are made and broken apart by dehydration

synthesis and hydrolysis.

Warm-Up:

1. What is dehydration synthesis?

2. What is hydrolysis?

10/11/18

Objective: Students will be able to describe the function of enzymes in our body and how they help us

to maintain homeostasis.

Warm-Up: Fill in the following table about macromolecules.

Organic Molecule Monomer Function

Carbohydrate

Lipid

Protein

Nucleic Acid

3.3 Enzymes

Enzymes

Enzymes are their own class of . Living things could not survive without

enzymes.

Without enzymes, chemical reactions of life would occur to to

survive.

o We call these substances a

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Examples of Enzymes:

Carbohydrases Enzymes that break down sugars.

Proteases Enzymes that break down proteins.

Lipases Enzymes that break down lipids.

Polymerases Enzymes that join molecules together.

Transferases Enzymes that transfer pieces of one molecule to another.

Enzymes and Substrates

is the term used to describe the molecules that an enzyme acts

upon.

o For example, amylase is an enzyme (a type of carbohydrase) that breaks down

polysaccharides into monosaccharides. The amylase attaches to the starch, which is the

substrate, and helps to break it down into individual glucose molecules.

Lock and Key/Puzzle

Enzymes and substrates follow the “ ” model. Each enzyme

only reacts with a .

o For example: if you are eating a cheeseburger for

dinner, amylase will only react with the starch

found in the bun. It will not break down the

other types of food molecules. Only one

substrate ( ) per enzyme (

)!

The of an enzyme is

the specific area of the enzyme where it bonds with the substrate.

Enzyme Substrate Complex

Once the substrate bonds with the enzyme, it temporarily forms an “

” until the reaction occurs.

Once the products are formed, they are released, and the enzyme is free to react again

(enzymes the products and to the next substrate).

o Example: the products of amylase and starch would be smaller glucose molecules

broken apart.

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Enzymes can also smaller molecules together, resulting in one large

product.

How do Enzymes Work?

Enzymes work by the bonds between monomers. This lowers the

activation energy.

o is the energy needed for a chemical reaction to occur.

What Affects Enzyme Activity?

1. Environmental Conditions

a. are the most dangerous

i. High temperatures may denature (unfold) the enzyme

b. -most prefer a pH of 6-8, near neutral

c. -especially salt ions

2. Cofactors and Coenzymes

a. (zinc, iron) and

(respectively) are sometimes needed for proper enzymatic activity.

b. Example: Iron must be present in the hemoglobin (protein) structure in order for it to

pick up oxygen.

3. Enzyme Inhibitors

a. : are chemicals that resemble an enzyme’s normal

substrate and competes with it for the active site.

b. : Inhibitors that do not enter he active site, but bind to

another part of the enzyme causing the enzyme to change its shape, which in turn alters

the active site.

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10/12/18

Objective: Students will be able to model the function of enzymes using manipulatives and explain how

enzymes help us to maintain homeostasis.

Warm-Up:

1. Meat tenderizer contains an enzyme that interacts with meat. If meat is coated with tenderizer

and then placed in a refrigerator for a short time, how do you think the enzyme will be affected?

2. What is the relationship between an active site and a substrate?

10/15/18

Objective: Students will be able to model the function of enzymes using manipulatives and explain how

enzymes help us to maintain homeostasis.

Warm-Up:

1. Enzymes have an optimum temperature at which they work best. Temperatures above and

below this optimum will decrease enzyme activity. Which graph best illustrates the effect of

temperature on enzyme activity? Explain your answer.

Vocabulary Builder: Vocabulary Battle Game

10/16/18

Objective: Students will demonstrate their knowledge of homeostasis an organic molecules on a unit

review.

Warm-Up: (2 Questions)

1. Go back to the front page of your packet and read through the essential outcomes. Put a

question mark next to the topics that you still have questions about. Put a check mark next to

the topics that you feel confident about.

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2. How are you going to go about learning those topics that have a question mark next to them?

10/17/18

Objective: Students will demonstrate their knowledge of homeostasis an organic molecules on a unit

test.

Warm-Up:

1. Turn in your work to the basket.