Question

1. when a persons level of physical activity changes, the circulatory system supplies body cells with amounts of nutrients and oxygen that are appropriate to sustain the new level of activity. this statement illustrates the concept of

(1) homeostasis (2) synthesis (3) digestion (4) pinocytosis

1. although the digestive system is primarily responsible for the breakdown of food, this process can be disrupted if the circulatory system malfunctions. the best explanation for this is that

(1) human body systems interact with each other to perform life functions
(2) the circulatory system controls the entire body
(3) the digestive system and circulatory system have the same organs
(4) the circulatory system breaks down food too

1. a man develops a severe infection in his lungs. this would impact the mans ability to

(1) digest food (3) transport nutrients throughout the body
(2) absorb oxygen and expel carbon dioxide (4) produce sex cells

1. which diagram best illustrates the function of a lung cell (alveolus) surrounded by a blood vessel (capillary)?

(1)
(3)
hint: look at what is entering and exiting the lung cell and blood vessel!
(2)
(4)

Explanation:

1. Homeostasis is the ability of the body to maintain a stable internal environment. When physical activity changes, the circulatory system adjusts nutrient and oxygen supply, which is homeostasis. Synthesis is making molecules, digestion is breaking food, pinocytosis is cell - drinking.
2. The digestive system breaks food, but needs the circulatory system (e.g., to transport nutrients). Body systems interact. The circulatory system doesn't control all, systems have different organs, and the circulatory system doesn't break food.
3. Lungs are for gas exchange (absorb oxygen, expel carbon dioxide). Digestion is stomach/intestines, transport is circulatory, sex cells are reproductive.
4. In alveolus - capillary exchange, oxygen enters blood (from alveolus), carbon dioxide exits (to alveolus). Diagram (2) shows \(CO_2\) and \(O_2\) movement.

Answer:

1. (1) homeostasis
2. (1) human body systems interact with each other to perform life functions
3. (2) absorb oxygen and expel carbon dioxide
4. (2)