Work Hard. Get Smart.

Notes

Cell Biologist’s Name: _____________________________ Class: 8__ Date: ______________ Mrs. Bouchard– 8th Grade Science

Respiration, Energy and Life Reading DIRECTIONS: Below are the directions you will follow during today’s partner reading activity. Read the directions, then answer the questions at the bottom. 1. This reading will be done “reciprocal teaching” style. You will be annotating for the answer to the question: “Why do the cells of all living things need to complete respiration?” 2. The Summarizer will read the first paragraph. The summarizer will give a short (less than 15 words) summary to the group before they move on the next paragraph. Everyone will write the summary down in the cloud next to that paragraph. - The summarizer of the group is: ___________________________________ 3. The predictor will read the second paragraph. The predictor will briefly describe what they think will be mentioned in the next paragraph or later in the text. - The predictor of the group is: ___________________________________ 4. The questioner of the group will read the third paragraph. The questioner will ask a question that is relevant to understanding the text. - The questioner of the group is: _________________________________ 5. The clarifier of the group will read the fourth paragraph. The clarifier will clear up any confusion about the paragraph or will explain what an important word from the text means. - The clarifier of the group is: ____________________________________

After all group members have read, the reading order starts back at summarizer again. This process continues at the end of each paragraph.

Congratulations! You are ready to read!

When you are done, you can check the answer key!

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Respiration, Energy and Life One of the big questions we’ll be asking this year is, “What does it mean to be alive?” So far, we know all living things are made of cells, and all living things use their cell membranes to achieve balance – taking in what they need, and getting rid of what they don’t need. Here’s one more: All living things, no matter how big or how small, need to acquire (get) and use energy. Humans? We need to use energy to move, and to use our brain to think. Plants? They need to use energy to grow and reproduce by making seeds. Bacteria? Even they need energy to move around. If you’re alive, you must need energy. You probably remember from our cells unit that the organelles called mitochondria are responsible for breaking down food to make energy. That’s why the mitochondria are like the power generators in a factory. Just like power generators provide factories with power, mitochondria provide cells with energy. However, we haven’t studied how exactly mitochondria make energy. Well, here we go. Mitochondria allow your cells (and the cells of many living things) to make energy through a process called respiration. During respiration, the mitochondria in your cells break down simple food molecules (such as sugar) and release the energy they contain.

You’ve reached the checkpoint! Now you and your partner must split up and try the reading and summaries by yourselves!

A Mitochondrion (Singular of Mitochondria)

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Now, your cells can’t store energy. So, your cells store food instead. When you eat, your body breaks down food into small molecules. If you don’t need the energy right that instant, your cells will store that food in vacuoles for later. When your cells need energy later, that’s when respiration begins. Respiration happens in two parts. First, food that your cells have been storing is broken down into tiny pieces of sugar. Even something like a hot dog can be broken down into sugar, when you break it down into small enough pieces. This happens in the cytoplasm of your cells. The second part of respiration happens in your mitochondria. Those tiny pieces of sugar enter the mitochondria, are combined with the oxygen that you breathe, and then broken down even further to release a huge amount of energy. This process also creates water and carbon dioxide gas as extra products, which you can then exhale (breathe out). When the mitochondria make energy through respiration, that energy is made as a small chemical called ATP. Once the mitochondria have made the ATP, it can be sent all over the cell and to other cells so they can use the energy. We have to make and use tons of ATP every day to power our legs, our arms, our mouths and our brains!

A Mitochondrion (Singular of Mitochondria)

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Work Hard. Get Smart. Scientist’s Name: _________________________________ Class: 8__ Date: ______________ Mrs. Bouchard – 8th Grade Science

Post-Reading Questions 1. Below are pictures of a caterpillar, mold and a fern. What do these organisms have in common?

a. They can make their own food.

b. They cause diseases.

c. They need energy.

d. They need to breathe oxygen.

Explain Your Answer: __________________________________________________________ ____________________________________________________________________________ 2. Which of the following is NOT a reason energy is important to a cell? a. Respiration produces the energy you need to move. b. Respiration allows your brain to think, read and solve problems. c. Respiration allows your cells to take in food through diffusion. d. Respiration produces the energy you need to live and grow. Explain Your Answer: __________________________________________________________ ____________________________________________________________________________ 3. Which of the following best explains the word respiration? a. When a cell dies naturally, without killing the entire organism. b. When a cell breaks down food to produce energy. c. When an organism made of cells breathes in oxygen. d. When a cell uses chloroplasts to make its own food.

Good start. Now keep going!

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Work Hard. Get Smart.

4. Which of these diseases would MOST prevent a cell from performing respiration? a. A bacterial infection that weakens the cell membrane. b. A parasite that disables your cell’s golgi body. c. A fungus that severely clogs up the cell’s endoplasmic reticulum. d. A virus that destroys all of the cell’s mitochondria. Explain Your Answer: __________________________________________________________ ____________________________________________________________________________ 5. Which of these diseases would have the LEAST effect on cellular respiration? a. A virus that causes your vacuoles to shrink in size. b. A bacteria that causes your ribosomes to produce less protein. c. A cancer that reduces the size of your mitochondria. d. A fungus that stops your lysosomes from breaking down food. 6. Which of the following is neither an ingredient nor a product of respiration? a. Sugar

b. Water

c. Salt

d. Oxygen

7. Which of the following best explains what ATP is? a. One of the key ingredients in respiration. b. The chemical that helps the cell membrane take in the oxygen it needs to live. c. The chemical that holds the energy produced by respiration. d. The name of the types of cells that can use respiration. 8. Which of the following is MOST like the process of respiration in cells? a. Going for a walk on the Charles River. b. Moving with a big crowd of people to where there are fewer people. c. Trying to collect all of the Easter eggs during an Easter egg hunt. d. Plugging your phone charger into the wall to give it the power to work.

You’re done! Raise your hand so your teacher can check your work.

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