CUA #4 Review

Priya, Mia, and Luna are learning about the human body. They want to know which system contains the esophagus, stomach, liver, and intestines. Can you help them?

•    digestive system 

• circulatory system

• respiratory system

• excretory system

In a lively biology class, Ava and Liam were having a friendly debate about where digestion begins in the human body. Suddenly, Priya, who was quietly listening, chimed in and confidently stated that digestion actually begins in the -

• mouth

• large intestine

• small intestine

• pancreas

On a chilly winter day, Jackson, Nora, and Henry are on a quest to understand how animals stay cozy and warm. They stumble upon the fact that animals munch on food for energy as they can't produce it themselves. Can you help them figure out the energy transformation that occurs when an animal eats food to stay warm?

• chemical to thermal

• mechanical to radiant

• mechanical to thermal

• radiant to chemical

It's pizza party time! Aria, Lily, Oliver, William, and Priya are all excited. Noah takes the first bite. Can you tell us what represents a physical change in the pizza when Noah munches on his slice?

• His saliva changing the starch in the pizza crust to sugar

• His teeth tearing off a bite of pizza

• The chemicals in his stomach digesting proteins

• The breaking down of fats in the pizza by Bile

Arjun, Ava and Maya are on a fun adventure, exploring the mysteries of granite, a hard igneous rock often used in making kitchen countertops. They find out that granite is mined at a quarry, where rock is cut from Earth's crust and broken into usable pieces. Suddenly, Arjun wonders out loud, 'Which part of the digestive process is most similar to granite mining?' What should Ava and Maya tell Arjun?

• The walls of the esophagus lubricate the food, helping it move to the stomach.

• Teeth break food into smaller bites.

• Food mixes with digestive juices in the stomach.

• Chemical digestion occurs as food moves through the small intestine.

During a lively biology class, Aiden, Ethan, and Elijah are having a friendly debate about mechanical digestion. They are trying to define it as –

• using a utensil to crush food before   

        consuming.

• not a necessary part of the digestive 

        processes.

• the physical breaking and crushing 

        of food.

• carried out in the lower intestine.

During a lively biology class, Anika, Nora, and Benjamin were having a friendly debate about the digestive process. Can you help them figure out which step in the digestive process represents a chemical change in food?

• Is it the storing of swallowed food in the stomach?

• Could it be the chewing of food in the mouth?

• Maybe it's the movement of food down the esophagus to the stomach?

• Or is it the substances in the mouth and stomach breaking down proteins and fats?

Organize these options into the right categories

Groups:

(a) Physical Change

,

(b) Chemical Change

• Saliva begins breaking down starches

• Gastric juices break down protein molecules

• stomach muscles mixing food

• Enzymes in the small intestine break down carbohydrate molecules

• shredding paper

• teeth chew food into smaller pieces

• boiling water

• popping popcorn

• burning a candle

• vinegar mixes with baking soda

At lunchtime, Aiden, Abigail, and Oliver were fascinated to see Benjamin munching on his sandwich. They noticed how his teeth were breaking down the food into tiny, swallowable pieces. This, they realized, was a perfect example of a (a)   .

• physical change

• chemical change

During a thrilling science experiment, Isla, Evelyn, and David noticed a peculiar change in a substance they were observing. Can you help them figure out if this is a physical change?

• A new substance is produced, but hold on, the new substance has properties identical to the original substance. Strange, isn't it?

• The properties of the substance may change, but no new substances are produced. It's like a magic trick, isn't it?

• An entirely new substance with new properties form as a result of the change. It's like a science fiction movie, right?

• The properties of the substance change for only a short time but will return to their original state. It's like the substance is playing hide and seek, isn't it?