Question Info

This question is public and is used in 1 group

Type: Multiple-Choice
Category: Nature and Science (Stories)
Level: Grade 6
Author: szeiger
Created: 2 years ago

View all questions by szeiger.

Nature and Science (Stories) Question

View this question.

Add this question to a group or test by clicking the appropriate button below.

Note: This question is included in a group. The contents of the question may require the group's common instructions or reference text to be meaningful. If so, you may want to add the entire group of questions to your test. To do this, click on the group instructions in the blue box below. If you choose to add only this question, common instructions or reference text will not be added to your test.

“Um, Ruby?” questioned Lydia, a young girl with braided hair.

“I don’t think I understand this,” Lydia spoke softly.

“Sure, you do!” exclaimed Ruby “It’s really easy. I’ll explain why.”

Ruby put down the dishes and went to Lydia, who was sitting at the kitchen table swamped with notes. In one brisk sweep, Ruby picked up all the notes and organized them into three stacks.

Ruby’s eyes scanned each paper before setting them into the stacks. Lydia watched her older sister with a hopeful heart. She needed to learn all about the heart for her science class.

“First things first, put your hand over your heart,” ordered Ruby.

“Lub-dub, Lub-dub. That’s the sound your heart makes when valves open, lub, and the sound it makes when valves close, dub.” Ruby’s voice was clear and strong, but Lydia’s face still looked puzzled.

“The blood in our body is always having fun. It works like a roller coaster ride. It is very important for our red blood cells to give oxygen to our muscles, so they can have the power to move.”

“I know that the white blood cells fight off illness,” interrupted Lydia.

Ruby smiled, “That’s right. I imagine them as white ninjas that silently destroy those baddies!”

“Anyway,” Ruby continued, “once the red blood cells have transported the oxygen to the muscles, they flow back to the heart in little tunnels called veins to get more oxygen.”

“Yeah, but does the blood become blue, like in the pictures?” Lydia pointed to her notes showing a diagram outlining the flow of blood in red and blue.

“I see,” Ruby said. “This is just the picture trying to help you out. Look, the blue part represents the red blood cells that need to go back to heart to fill up with oxygen. Right now they are deoxygenated. The red part is the red blood cells with oxygen on their way to different muscles. In truth, our blood will become dark red without oxygen and bright red with oxygen.”

Lydia’s eyes widened, “That makes sense. Okay, so the deoxygenated blood goes back to the heart to get more oxygen.”

Ruby nodded.

Then Lydia slouched in her chair. “There are so many parts in the heart for the red blood cells to go through; it’s like a maze.”

Ruby put her hand to the bottom of her chin and thought for a moment. Then she pulled one of Lydia’s notes from a stack. It was a picture of the heart. Ruby pointed at the top of the heart and said, “This is where the red blood cells enter; it’s called the right atrium, one of four chambers of the heart.”

Ruby’s finger glided down. “Next the red blood cells will pass the first gate; it’s
called the tricuspid valve. Then it will enter the right ventricle.”

Lydia’s eyes followed Ruby’s finger as it slid to the lungs.

“Now the red blood cells will receive oxygen from the lungs and come back to the heart so it can be delivered to the muscles. The red blood cells rich with oxygen will enter the left atrium."

“Wait, I’m lost” said Lydia. “You’re moving too fast!”

“Oh? Well, what’s wrong?”

“How do you know that this is the left atrium?”

Ruby answered, “I remember because the letter ‘A’ comes before ‘V’ so, the atrium comes before the ventricle.”

“That means the red blood cells will leave the heart through the left ventricle!” Lydia beamed.

“Yes, but don’t forget that the blood will also pass another gate, it’s the bicuspid valve.”

Lydia’s expression changed “How can you tell the valves apart?”

“It’s in the name,” explained Ruby, “Tricuspid has the prefix tri which means three while bicuspid has the word bi meaning two. Think of it as a count down, three then two.”

After that, Lydia explained the whole process to Ruby who gave her approval.

“See, I told you it was easy!”

On test day, Lydia was nervous and doubtful about her ability to pass. Then she put her hand over her heart and felt the gentle beat against her chest and thought lub-dub, lub-dub. A slow smile spread across her face and she began the test.

Grade 6 Nature and Science (Stories)

What sound does the heart make when the valves close?
  1. lub
  2. dub
  3. thump
  4. bump
You need to have at least 5 reputation to vote a question down. Learn How To Earn Badges.