digestive, respiratory and circulatory system Flashcards
What is the function of the heart, lungs and blood?
The heart pumps blood to the rest of the body.
The lungs are the site of gaseous exchange
The blood transports substances around the body, such as oxygen, digested food, carbon dioxide and waste products
Blood vessel A flows from the lungs to the heart. Describe how the lungs, small intestine and the heart work together in to transport of substances in the body.
-At the lungs, oxygen is taken in and absorbed into the blood
-Digested food in the small intestine is digested and absorbed into the blood
-The heart pumps the blood rich in oxygen and digested food to the rest of the body.
-The heart will also pump blood containing carbon dioxide from the rest of the body back to the lungs to be removed from the body
Blood vessel A is flowing from the lungs to the heart. A person suffering from a diseases has part of blood vessel A blocked. As a result, their breathing rate increases. Explain why the breathing rate of a person suffering from this disease increases.
As blood vessel A is blocked, oxygenated blood will be pumped slower to the rest of the body. The body needs to take in oxygen faster in order to have sufficient oxygen supplied to the body.
Explain why our heart rate increases when we are exercising.
Our heart rate increases as our heart pumps blood faster to transport more oxygen and more digested food to the rest of the body to release more energy for the exercise. The heart also pumps blood away from the body parts faster to remove waste products and carbon dioxide faster from the body cells
Explain why our heart rate decreases when we stop exercising.
The heat pumps blood slower as to transport less oxygen and digested food to body cells as less energy is needed now. There is less blood pumped away from the other body parts to remove less carbon dioxide.
State the function of the digestive system
To break down food and absorb the substances into the bloodstream to be used by the body.
Describe how the oxygen in the air we inhale is transported from the air to our arm.
When we breathe in, our lungs take in the air. The oxygen in the air is then absorbed into the blood. The oxygenated blood is then pumped by the heart to our arms.
Explain why the mass of undigested food in the large intestine decreases.
Explain why there is some undigested food moving into the large intestine.
In the large intestine, water is constantly being absorbed from the undigested food into the blood stream, decreasing the mass of the undigested food
There is still food that cannot be digested or is difficult to be digested.
In which parts of the digestive system does digestion take place?
Mouth(Saliva), Stomach, Small intestine, Large intestine
Blood vessel A flows from the heart to the blood vessels in the lungs while blood vessel B flows form the heart to the blood vessels in the small intestine.
(a) Explain why blood vessel B is rich in oxygen while blood vessel A is poor in oxygen.
(b) When blood vessel B is partially blocked, how does that affect the function of the small intestine?
(a) Blood in B is rich in oxygen as it comes from the lungs where oxygen is taken in and absorbed into the blood. Blood in A is poor in oxygen as the oxygen in the blood has been used up by the other body parts for cellular respiration.
(b) Blood flow to the small intestine is slower. Thus, the rate of digestion will decrease.
Why does the heart keep beating, even when we are sleeping?
Cells need energy for life processes, even when we are sleeping, thus the heart pumps blood to transport oxygen and digested food needed by the cells. Blood would also transport carbon dioxide and waste products away from the cells.
Alissa had a heavy breakfast two hours before going for a swim. The food that she had eaten was digested into sugar, which provides energy for the body.Describe how the food Alissa had eaten reaches the other parts of her body.
When swimming, the volume of blood supplied per minute to the hands and legs is greater than when resting, while the volume of blood supplied per minute to the small intestine is less than when resting. After swimming immediately after eating, Alissa felt some discomfort in her stomach as there was too much food remaining in her stomach. Explain why.
Digested food will be absorbed into the blood and the heart pumps the blood containing digested food to the different prats of the body.
When Alissa was swimming, less blood was supplied to the stomach per minute, resulting in a decrease in the rate of digestion in her stomach, thus less food is absorbed into the bloodstream.
Water enters the fish’s mouth when it is open and passes through part X before leaving the fish.
Describe how gaseous exchange takes place in the fish
Water enters the fish’s mouth and is forced through part X. The blood absorbs the dissolved oxygen in the water and removes the carbon dioxide into the water at Part X
How is the flow of blood in the fish circulatory system different from that of the human circulatory system.
In the human circulatory system, the blood goes through the heart twice in a complete cycle while in the fish circulatory system, the blood goes through the heart only one./In the human circulatory system, the blood travels in double circulation while in the fish circulatory system, the blood travels in single circulatory system
