举一反三
- which type of epithelium is thin and leaky and lines blood vessels and the air sacs of the lungs A: Stratified squamous epithelium B: Cuboidal epithelium C: Simple squamous epithelium D: Simple columnar epithelium
- Ventilation in birds is accomplished by expansion and contraction of the ( ). A: air sacs B: trachea C: lungs D: diaphragm E: air capillaries
- If the _______ stops beating, no blood can flow through the body.() A: heart B: lungs
- 词汇与结构 This relationship between temperature, altitude, and air density can be expressed as a _______ altitude, or the altitude in the International Standard Atmosphere at which the air density would be equal to the actual air density.
- A process by which information is exchanged between individuals through a common system of symbols, signs, or behavior, or the exchange of thoughts, messages, or information, as by speech, signals, writing, or behavior.
内容
- 0
Which of these functions cannot be attributed to the mucous membrane that lines the nasal cavity? A: warms incoming air B: filters particles from incoming air C: moistens incoming air D: initial gas exchange between air and blood occurs here
- 1
Which of the following refers to the retention of the Sun's warmth in the Earth's lower atmosphere by greenhouse gases?
- 2
what the analogy is: which two things are being compared?The earth’s atmosphere is like a blanket of gases around the earth. It is only a thin layer but it helps to maintain the temperature of the earth, keeping us warm. It also offers a layer of protection from the intensity of the sun. A: earth’s atmosphere and a blanket B: earth’s atmosphere and gases C: earth’s atmosphere and a layer of protection D: earth’s atmosphere and a blanket of gases
- 3
（ ） are any of the small air spaces in the lungs where leaves the and oxygen enters it. A: Cilia B: Bronchioles C: Tracheae D: Pulmonary alveoli
- 4
In an engine with air inlet valve and exhaust valve on its cylinder heads the fresh air will enter into the cylinder （） and the gases exhaust （）， there being an adequate overlap between the inlet opening and the exhaust closing.