Please answer all questions

1		Air passing along the respiratory tract to the lungs is ______.
			A)	cleansed
			B)	warmed
			C)	moistened
			D)	all of the above
2		The nasal cavities empty into the __________.
			A)	eustachian tubes
			B)	lacrimal glands
			C)	larynx
			D)	nasopharynx
3		The __________ tubes lead from the nasopharynx to the middle ears.
			A)	bronchi
			B)	auditory
			C)	nasal
			D)	trachea
4		The pharynx consists of three parts except _____________.
			A)	nasopharynx
			B)	oropharynx
			C)	trachea
			D)	laryngopharynx
5		The __________ houses the vocal cords.
			A)	larynx
			B)	bronchus
			C)	pharynx
			D)	esophagus
6		The trachea divides into two __________ that lead to the lungs.
			A)	glotti
			B)	tracheae
			C)	bronchi
			D)	bronchioles
7		Each bronchiole terminates in an elongated space enclosed by a multitude of air pockets called __________.
			A)	the glottis
			B)	alveoli
			C)	the larynx
			D)	the pharynx
8		Each alveolar sac is surrounded by __________ carrying blood.
			A)	arteries
			B)	veins
			C)	capillaries
9		The amount of air moved in and out with each breath is called __________.
			A)	inspiratory reserve volume
			B)	tidal volume
			C)	expiratory reserve volume
			D)	vital capacity
10		Normally, the pressure between the pleural membranes that surround the lungs and line the thoracic cavity is ____________ atmospheric pressure.
			A)	lower than
			B)	higher than
			C)	the same as
			D)	None of these is correct.
11		The respiratory center that triggers inspiration is located in the _______.
			A)	thorax
			B)	alveoli
			C)	medulla
12		Chemical receptors in carotid bodies respond to _______.
			A)	hydrogen ion concentration
			B)	levels of carbon dioxide in the blood
			C)	levels of oxygen in the blood
			D)	all of the above
13		During expiration, __________ pressure in the thoracic cavity causes air to leave the lungs.
			A)	increased
			B)	decreased
			C)	gradually decreasing
			D)	no
14		During __________, the respiratory pigment hemoglobin combines with oxygen to form oxyhemoglobin in the pulmonary capillaries.
			A)	internal respiration
			B)	external respiration
			C)	anaerobic respiration
			D)	ventilation
15		The exchange of oxygen and carbon dioxide between alveolar air and blood is governed by _______.
			A)	gravity
			B)	blood pressure
			C)	diffusion
16		Most of the carbon dioxide is being carried as __________ as blood enters the pulmonary capillaries.
			A)	carbaminohemoglobin
			B)	calcium carbonate
			C)	bicarbonate ions
			D)	hydrogen ions
17		Chronic bronchitis is caused by ______.
			A)	a bacterial infection
			B)	a viral infection
			C)	constant irritation of the lining of the bronchi
18		Inhaling particles such as silica, coal dust, and asbestos can lead to _______.
			A)	pneumonia
			B)	tuberculosis
			C)	pulmonary fibrosis
			D)	all of the above
19		The events involved in the formation of lung cancer are ______.
			A)	thickening and callusing of cells lining the bronchi
			B)	loss of cilia
			C)	formation of cells with atypical nuclei
			D)	all of the above
20		How does the respiratory system contribute to homeostasis?
			A)	by accomplishing gas exchange
			B)	by helping to regulate the pH of the blood
			C)	both A and B