Unit 2 BioChem, Digestion, Enzymes & Cell Respiration

QUIZLET REview 1 https://quizlet.com/_5khv52

Quizlet REview 2 w/ pictures (also study the one above): https://quizlet.com/_5ptm1u

Quizlet 3 - Cellular Respiration https://quizlet.com/467402173/cellular-respiration-flash-cards/?new

This picture below shows some of the indicators used in the food lab. All indicators change color when they are mixed with the chemical they test for. (Benedicts solution must first be heated to obtain your results for simple sugars.)

Next, we will look at the chemical composition of our food molecules to see what atoms or elements they are made of and to see how small building blocks (or monomers), like glucose, can be used to build more complex molecules (polymers) like starch or cellulose.

(See below for packet with the directions from class!)

We begin this unit by looking at the molecules that make up our foods and our own cells. We will start with a basic overview of the 3 major classes of organic molecules in our food - carbohydrates, lipids (fats & oils), and proteins. We will test foods using chemical indicators to see which foods contain each of these molecules in large amounts. As part of our understanding of lactose intolerance, we will test milk to see what types of organic molecules it contains.

https://quizlet.com/467402173/cellular-respiration-flash-cards/?new

--> WHAT IS LACTOSE INTOLERANCE? We started this unit by asking students to explain what they know about how lactose intolerance works. As a post-unit assessment, students should be able to explain lactose intolerance touching on 4 different topics in class: organic chemistry, enzymes, digestion and cellular respiration.

Above is a cartoon picture of the organic molecules we are studying. In addition to carbohydrates, lipids and proteins, scientists recognize a fourth group of organic molecules called nucleic acids. This is the group of molecules that DNA and RNA belong to. We will talk about them in much greater detail next semester. While these are simplified pictures of each molecule, they do help to teach important information about each molecule. Can you name them all ????

Then, in order for food to become structures in our own cells, it must be changed. Plant proteins must be turned into animal proteins. This process begins with the process of digestion when our food is broken down and with the help of enzymes. Here we will learn a little bit more about our digestive system and the structures within it that make this process possible. We will also look more closely at enzymes to better understand their actions in the body. These notes will mostly focus on answering these two questions:

1) Where is each food item first chemically broken down in the digestive tract?

2) What enzyme breaks down each of the food molecules discussed?

We will briefly discuss how food is absorbed mostly through the villi of the small intestines into the bloodstream. The idea behind digestion is to make molecules small enough to be transported through the layer of cells in the intestine wall and into the blood. From the blood, these building blocks circulate to all our different body cells. Once in our cells - they can be used for energy, stored for energy later, or used to build parts of the cell!

In addition, we will talk about food items that are not able to be digested, and we will discuss their fate. We previosly discussed the role of bacteria in maintaining healthy digestive tracts. Here we will learn a little more about what bacteria do for us!

Lastly, we will dive deeper into how our cells use glucose and other molecules for energy - in other words - metabolism. We will learn how there are two different pathways for metabolism, aerobic respiration versus anaerobic respiration. We will compare and contrast these two pathways especially in terms of energy produce and the products of each pathway.

In the end, you should thoroughly be able to explain how food is digested and what is occurring when someone is considered "lactose intolerant."

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These are some additional questions I hope you find interesting and that I hope you will be able to answer by the end of this unit!

Some additional topics to explore that relate to this unit include:

    • What is high-fructose corn syrup and what is the big hype about it?

    • What is heartburn and how is it related to diet?

    • How is blood sugar controlled by our body and what goes wrong in Type 1 and Type 2 diabetes?

TOPIC 1: Organic Chemistry (Biochem)

My Organic Molecule lecture (these are old versions --I cut some content!)

Part 1: https://vimeo.com/188241063/

Organic Molecule Lecture part 2 (click on it!)

Learning objectives for Organic Chemistry

  • State how scientists classify organic molecules (recognize the abstract pictures representing chemical structures)

  • Describe the indicator tests for each of the following molecules and describe what a positive test looks like & give examples of foods that tested positive for each.

  • Describe the chemical make-up of carbohydrates, lipids and proteins on an atomic level. (e.g. What atoms are each composed of and which atoms are most abundant in each molecule? What are the shapes of the building blocks of these molecules?)

  • Explain what happens to food after we eat it and how animals use food for growth and storage. Give specific examples of uses of different carbohydates, proteins and fats in the body of animals and plants.

EXTRA REVIEW ON ORGANIC CHEMISTRY:

Crash Course Video on O-chem:

Some of the basics of Organic Chemistry from the Amoeba sisters:

A really good source for further explanation of organic chemistry:

http://cnx.org/contents/14fb4ad7-39a1-4eee-ab6e-3ef2482e3e22@6.24:15/Anatomy_&_Physiology

THIS PICTURE BELOW SHOWS SOME OF THE USES OF ORGANIC MOLECULES IN THE CELL!

How much energy does our food contain? See how we measure the energy content of food. https://www.youtube.com/watch?v=PgDxS3cpuX4 (We did not get to this in 2019)

TOPIC 2: Digestion

Learning Objective 1: Describe what happens to food after we eat it including where each molecule is first broken down in the digestive tract and how those molecules get to body cells where they are used for growth, storage and energy.

More specifics:

    • Describe how food molecules are broken down by the digestive tract (at this point you should know where each is first digested!)

    • Describe what kinds of molecules are able to pass through the small intestine wall into the blood. (Small ones!)

    • Describe the role of the blood in delivering food molecules (and the role of Red Blood Cells to specifically deliver oxygen to cells).

    • Give examples of molecules that the cell builds with the building blocks including glycogen, lipids, phospholipids, new proteins (give some specific examples of proteins in the body).

    • Describe which food molecules are used for quick energy, long term energy storage and a last resort for energy (proteins).

Learning Objective 2: Describe the structures (organs) of the digestive system and what features make them special and allow them to perform a specific job within the digestive system.

More specifics:

  • Know the role of smooth muscle throughout the digestive tract.

  • Know the role of salivary amylase in the mouth.

  • State 2 purposes of acid in the stomach.

  • Know the role of villi and microvilli in the small intestine.

  • Know the role of bacteria in the large intestine.

LACTASE MINI-LAB RESULTS:

The above picture shows glucose test strips ( a paper chemical indicator).

Can you explain the difference between the results of the milk and the milk with lactase?

Why did the milk with lactase turn green?

Crash Course on the Digestive System:

Bozeman Science & The Digestive System --- A GREAT RESOURCE!!!!

TOPIC 3: ENZYMES

Learning objective: Explain how enzymes play a role in biological reactions.

What this really looks like:

  • Know the definition of the following terms and be able to label them on a picture: substrate (or reactants), product, active site, and enzyme

  • List 3 factors that affect enzyme activity and describe how or explain why (see your class notes) - how does this relate to what they are made of?

  • Define and identify the following terms in our enzyme lab: manipulated variable, responding variable, controlled variables, experimental control. What was the enzyme and what was the substrate?

  • Explain how enzymes are named and how they are specifically shaped for their specific job - building or breaking molecules.

  • Describe the processes of dehydration synthesis and hydrolysis when building molecules and breaking molecules.

While the picture below shows enzymes breaking down a molecule, remember they are also used to build molecules!!!!!!!!!!!!!!!!!!

WHAT CAUSES LACTOSE INTOLERANCE?

HHMI VIDEO shown in class: https://www.youtube.com/watch?v=umiLaW5AmKg

Answer the following questions during the video:

Want more practice with lactose intolerance? Write captions for this silent video or explain what is going on to a parent as you watch it together!

https://www.youtube.com/watch?v=w_KR6k6YIIs

Enzyme Video Shown in Class:

EXTRA ENZYME REVIEW:

Short, basic introduction to enzymes: (but a bit dull)

https://www.youtube.com/watch?v=r1ryDVgx0zw

A short video about enzymes and their names important to the body:

http://www.youtube.com/watch?v=myORDWVzNhc&safe=active

Take this ENZYME practice quiz ---while it has some grammatical issues, it is pretty helpful.http://www.biologycorner.com/quiz/qz_enzymes.html

TOPIC 4 - CELLULAR RESPIRATION

Be careful going to internet resources to review cellular respiration. Our class notes really just skim the surface of this topic. Most videos and tutorials will go into much greater detail. Please study this topic from our class notes. Be able to compare and contract aerobic verses anaerobic respiration.

Also, describe what alcoholic fermentation is and how it is different from lactic acid fermentation!