Accelerated Learning STEMscopes Feedback Mechanisms Accelerated Learning STEMscopes

Day 1

Homeostasis What does homeostasis mean? Homeostasis refers to the process by which organisms keep internal conditions, such as body temperature and blood pressure, relatively constant, despite changes in the external environment. An organism responds to external stimuli by trying to bring its body back into equilibrium. Maintenance of homeostasis requires the integration of all organ systems at all times. For example, the regulation of body temperature requires the nervous, circulatory, and endocrine systems.

How does the balance relate to homeostasis?

“Why is water necessary for biological organisms?”

Picture 1 What is happening? Why it is occurring? How does it help the organism maintain internal balance? Please include the words homeostasis and equilibrium in your responses.

Picture 2 What is happening? Why it is occurring? How does it help the organism maintain internal balance? Please include the words homeostasis and equilibrium in your responses.

Picture 3 What is happening? Why it is occurring? What is going on with the internal balance? Please include the words homeostasis and equilibrium in your responses.

Picture 4 What is happening? Why it is occurring? How does it help the organism maintain internal balance? Please include the words homeostasis and equilibrium in your responses.

Day 2 To Do 1: Homeostasis and Feedback Loops Description (Part 1)

Bellwork October 23 & 24 List two things you do that require balance. What is the main organ (or system) that controls your balance?

To Do 1: Homeostasis and Feedback Loops Description (background information)

Today’s Goal Complete Pre-lab through Part 1 #2 in Homeostasis and Feedback Loops on Canvas. Part 1: With your partner select a stimulus that can be tested in the classroom you can do in 1 minute increments.

Investigation You will conduct an experiment to measure the changes in your blood pressure, heart rate, and breathing rate after a given stimulus. Many stimuli exist that can cause changes (in either direction) to these systems such as running in place, holding your breath, lying down, and doing push-ups. With your partner select a stimulus that can be tested in the classroom you can do in 1 minute increments. Complete Pre-lab through #2 in Homeostasis and Feedback Loops on Canvas.

Day 3 To Do 1: Homeostasis and Feedback Loops Description (Part 2)

October 26 Bellwork What activity did you choose to do?

Today’s Goal Complete all of Part 1 and the data table (including data) in Part 2 in Homeostasis and Feedback Loops on Canvas. Independent variable: change Dependent variable: measuring Control: kept the same Be sure to collect your resting heart rate, and breathing rate before beginning this activity.

October 30 Bellwork: Think back to the examples you gave at the beginning of the lab of things that require balance. What is the difference between the balance in those examples and the balance that your body maintains (homeostasis)?  Your body maintains balance (homeostasis) involuntarily. All of these other examples are done voluntarily. Since the balance required inside your body is necessary for life, your body acts on its own, without waiting for a voluntary response from you; your life depends on this response.

Complete all of Part 2 in Homeostasis and Feedback Loops on Canvas. Today’s Goal Complete all of Part 2 in Homeostasis and Feedback Loops on Canvas. Title your graph, label your axes, include the units of measure, and provide a legend. Feel free to use https://nces.ed.gov/nceskids/createagraph/ to create your graph (you’ll copy and paste this into Canvas) OR you can draw a graph and take a picture to insert into Canvas

Don’t forget to fill this out!! Create a Graph Website Drawing your Graph Don’t forget to fill this out!!

Complete Part 2 Based on the procedure you outlined in Part I, draw a table to record the data you collect. Use one column for “Before Stimulus” one column for "During Stimulus" and one column for “After Stimulus.” Include one row each for blood pressure, heart rate, and breathing rate. Include units. Remember, in order to measure any changes, you must know the initial values, so be sure to collect your baseline blood pressure, heart rate, and breathing rate before beginning this activity. Develop a bar graph that communicates your findings before, during and after the stimulus. Title your graph, label your axes, include the units of measure, and provide a legend. Use additional paper as needed. Homework: Finish the conclusion questions.

October 31 Happy Halloween!! Bellwork What are some similarities between plants and animals?

Start Do 3 under system interactions on Canvas Part 1 Label the diagram in canvas as directed. Follow the directions in canvas making sure to use the appropriate colors to draw and label the plant's organization. Answer the questions in canvas and then move on to Part II. Part 2 During this investigation, you will view two plants: a normal plant and a dehydrated plant. Record your comparison observations of the two plants paying attention to the roots, stem, and the leaves. Plant

November 1 Bellwork What are some environmental changes that would cause plants to respond in order to maintain equilibrium to sustain life?  Environmental changes that would require plants to maintain homeostasis include, but are not limited to, droughts, floods, heat waves, lack of sun, lack of nutrients, etc.

Continue Do 3 under system interactions on Canvas Part 3 Obtain a leaf sample from your teacher. Paint a small patch of clear fingernail polish the size of a quarter on the underside of the leaf. After the polish dries, stick a piece of clear cellophane tape over the dried polish. Carefully pull up on the tape, making sure to pull off the clear nail polish along with the tape. Tape the tape on a clean microscope slide. Place the slide under the microscope and, starting on scanning power, focus in on the leaf. Once in focus, move to low power, then to high power, focusing after switching each power. Make sure to follow directions in canvas.

Day 4 - 7 To Do 2: Homeostasis in Plants

November 2 Bellwork What are some examples of feedback mechanisms in the body? Temperature, blood pressure, metabolism, blood sugar regulation, blood clotting, contractions at childbirth, etc.

Homeostasis in your body … Maintaining stable levels of fluid, temperature, energy, etc. in your body involves multiple systems! Different problems require different systems to respond, but there is a basic plan…

Feedback Loops Your body maintains homeostasis through a process called a “Feedback Loop” Problem Control Center Receptor Effector Response Feedback

So…. Something goes wrong! Your body detects the problem (receptor) The receptor sends a signal to the control center (your brain) Your brain sends a signal by nerves, hormones, etc. to the site of the problem. A change or response occurs. The “feedback loop” is when the receptor signals if the problem is fixed or if more adjustment needs to happen.

Two types of Feedback Negative Feedback is when a system counteracts, or goes against, the change to bring it back to normal. Example: you’re cold, so your body shivers to warm you up

Two types of Feedback Positive Feedback is when the system amplifies (increases) the response to make it happen faster. Example: you’re scared, so your body sends out adrenalin to make you escape faster

Sometimes feedback can go wrong! Explain Video: Diabetes and Insulin

Create a Poster (due end of day tomorrow) Select a feedback mechanism. Create a schematic (a symbolic diagram) that shows how the body regulates its inner environment to respond to external changes. Be specific in identifying the particular chain of reactions that occur. Use arrows to identify order. Label the following: Receptor Effector Control center Identify the mechanism as positive or negative, and identify the body system that controls the feedback mechanism.

November 3 Bellwork Would childbirth be positive or negative feedback? Explain.

Create a Poster (due today) Select a feedback mechanism. Create a schematic (a symbolic diagram) that shows how the body regulates its inner environment to respond to external changes. Be specific in identifying the particular chain of reactions that occur. Use arrows to identify order. Label the following: Receptor Effector Control center Identify the mechanism as positive or negative, and identify the body system that controls the feedback mechanism.

Day 8 & 9 To Do 3: Balancing the Body

Post-Activity Questions What are some examples of feedback in real life? What is one thing you learned from researching and diagramming feedback mechanisms?

Day 10 To Do 4: Homeostasis Reading Activity

Negative Feedback Negative Feedback Loop – when one “thing” is increased, another “thing” is decreased (or vice versa) Has nothing to do with BAD outcome Most common control mechanism

Positive Feedback Positive feedback loop – amplifies or increases change Has nothing to do with a good outcome.

Reading Activity You will be placed into teams of three. I will pass out several reading articles. Each person on the team should read one of the articles individually. After reading the article, each person will then complete the individual CER. 10 minutes Upon completion of the CER, rejoin your teams and take turns sharing what you wrote. As each person shares, group members should take notes in the "Sharing Notes Space" provided on the Student Handout. 2 minutes Homework: revise your CERs based on your team members’ suggestions.

Day 11 Linking Literacy