Gas Exchange

a protein that can bind four molecules of oxygen

Hemoglobin

After blood becomes oxygenated,

it returns to the heart, and is then pumped to body cells.

In the blood, oxygen is bound to hemoglobin, a protein found in red blood cells.

Which statement is correct?
1. Oxygen diffuses from large blood vessels into the body's cells.
2. In the blood, oxygen is bound to hemoglobin, a protein found in red blood cells.
3.Oxygen is released from the mitochondria as a product of cellular respirat

From which structures do oxygen molecules move from the lungs to the blood?

Alveoli

During inhalation,

the diaphragm and rib muscles contract

Carbon dioxide transport

1. Carbon dioxide is released from mitochondria
2. Carbon dioxide diffuses into a capillary
3. Carbon dioxide Is carried to the lungs
4. Carbon dioxide diffuses into a alveolus
5. Air exits through the nose or mouth

Oxogen transport

1. Oxygen diffuses from the alveoli into surropumding capillaries
2. Oxygen enters a red blood cell
3. Oxygen binds to a molecule of hemoglobin
4. Oxygen carried through blood vessels to a capillary
5. Oxygen diffuse from the blood to the body's tissues

Which of the following normally contains the highest concentration of oxygen?

air entering the respiratory system

In saltwater and freshwater environments, _____.

the concentration of oxygen in water is lower than in air

The human nose is involved in _____.
1. producing mucus
2. exchanging gases with the capillaries
3. filtering the air
4. gas exchange with the trachea

filtering the air

Humans can talk and sing because they can _____.
1. tense and relax the vocal cords as air flows past them
2. regulate the flow of air through the nose
3. contract and relax the diaphragm
4. modulate the flow of air through the trachea

1. tense and relax the vocal cords as air flows past them

Cigarettes contain over _____ different chemicals.

4000

About how many years after quitting smoking does it take for the risk of heart disease and death to return to levels similar to those seen in people who never smoked?

15

If you relax a tense abdomen during diaphragm contraction, what effect does this have on breathing?

It increases the vital capacity of the lungs

Which of the following statements about the breathing methods of mammals and birds is true?

Ventilation in mammals is bidirectional, but that of birds is not.

If you hold your breath, which of the following initially urges you to breathe again?

rising carbon dioxide concentration

What adjustment would make gas exchange more efficient in extracting oxygen from air?

hemoglobin with a greater affinity for oxygen

Which of the following options correctly lists the sequence of structures that air passes through during breathing after it enters the mouth and nose

pharynx, larynx, trachea, bronchi, bronchioles, alveoli

What is the specific site of gas exchange in the respiratory system?

alveoli

Contraction of the _____________ causes expansion of the lungs.

diaphragm

The ____________ and the ____________ are commonly known as the voicebox and windpipe, respectively

larynx; trachea

Asthma causes constriction of the tiny air passages in the lungs, otherwise known as the __________.

bronchioles

What type of breathing ventilates the lungs?

Negative pressure breathing

Steps of breathing or Negative Pressure Breathing.

Inhalation
1. rib muscles contract
2. air enters body
3. diaphragm contracts (moves down)
Exhalation
4. air leaves body
5. rib muscles relax
6. diaphragm relaxes (moves up)

Path of air to lungs

1. Air enters through the nose or mouth
2. Air travels down the trachea and enters the bronchi
3. Air travels down smaller and smaller bronchioles
4. Air reaches small sacs called alveoli

Key events in gas exchange

1. breathing moves air in/out of lungs
2. oxygen diffuses from alveoli in lungs into capillaries
3. oxygen enters red blood cells, where it binds to protein hemoglobin.
4. oxygen diffuses from blood to body's tissues, and carbon dioxide diffuses from the

One advantage of gas exchange in water over gas exchange in air is _____.
1. the respiratory surface does not have to be as extensive in water
2. water is easier to move over the respiratory surface
3. the respiratory surface does not dry out in water
4.

3. the respiratory surface does not dry out in water

In humans, incoming air is filtered, warmed, and humidified in the _____.

nasal cavity

In mammals, what happens during inhalation?

The diaphragm contracts and moves down.

Your breathing rate increases as, in your blood, your _____, which causes a _____ in pH.

carbon dioxide levels increase ... drop

Which of the following statements is true regarding the amount of oxygen bound to hemoglobin?
1. Binding of oxygen decreases in the presence of a high oxygen partial pressure.
2.Binding of oxygen alters the partial pressures of gases and triggers the cont

Binding of oxygen increases in the presence of a high oxygen partial pressure.