By: Katherine Pease 7 th Grade Science. 1. What organelle performs similar tasks to the excretory...

By: Katherine Pease

7th Grade Science<a href="http://www.dazzlejunction.com/" title="Glitter Graphics"><img

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1. What organelle performs similar tasks to the excretory system?

•Lysomes : they remove waste from the cell.

•The Excretory System removes waste from the body.

2. What are the major organs of the digestive system and what job

do they perform?• Liver: produces bile, a liquid that is stored

in the gall bladder. Bile is released into the small intestine, where it breaks up large fat molecules

• Pancreas: enzymes made here help break down carbohydrates and protein in small intestine.

• Stomach: grinds the food into smaller pieces, gastric juices and acids break apart large protein molecules.

• Small Intestine: Nutrients are absorbed through the villi, where most digestion occurs.

• Large Intestine: Material can not be digested, liquids are absorbed, the solid is waste we call feces that leaves the body through the rectum and anus.

3. What occurs in the stomach?

• Muscles in the stomach grind food into smaller pieces. Gastric Juice and hydrochloric acid made in the stomach breaks apart large protein molecules.

4. What occurs in the small and large intestines?

• Materials that cannot be digested move into the large intestine. The large intestine absorbs much of the water still trapped in the food waste. The solid that remains is called feces.

5. Breakdown of food in the mouth is an example of what type of

change?

• Mechanical: Teeth grind food into smaller pieces.

• Chemical: Saliva begins to break down complex starches into smaller sugars.

6. Identify various physical and chemical changes that occur in

digestion and label each.• Physical: Teeth break down food into smaller

pieces / stomach muscles grind food into smaller pieces

• Chemical: Saliva reacts with food to break it down / Bile reacts to break down fat molecules / Gastric Juice and hydrochloric acid react to break apart large protein molecules / Pancreas produces enzymes that react to break down carbohydrates

7. Differentiate between a physical and chemical change.

How are they similar and how are they different?

• Physical breaks down the appearance but not what the substance is.

• Chemical breaks down the substance by forming a new substance.

• Both break particles into smaller pieces

8. What foods contain carbohydrates?

9. What do you call the substances in your mouth which help break

down food?

• Saliva

10. What do you call the substances in your stomach which

help break down food?

• Gastric Juices

• Hydrochloric Acid

11. What do you call the substances in your pancreas which

help break down food?

• Enzymes

12. Use a flow chart or a diagram to show the transformation of

energy from breakfast or lunch through your day.

13. Describe the role of digestion in the transformation of energy.

•Absorption•Chemical / Physical

14.What compound is broken down in the digestive system for

the mitochondria to burn for energy?

•Food / Nutrients•Carbohydrates to sugars

• www.plummerpumasscience.yolasite.com

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