Gaseous Exchange

Question 1

Breathing

Answer 1

A mechanical process moving air in and out of the lungs.

Question 2

Gaseous Exchange

Answer 2

The exchange of gases across a respiratory surface.

Question 3

Respiration

Answer 3

The release of energy from food when it is broken down.

Question 4

Why is breathing necessary for life?

Answer 4

For oxygen

Question 5

Why is oxygen needed?

Answer 5

Oxygen is needed for the oxidation of food to release energy during respiration.

Question 6

Why does carbon dioxide need to be removed from the body?

Answer 6

If not removed it will form carbonic acid which will lower the pH of the body.

Question 7

How is carbon dioxide produced in the body?

Answer 7

Carbon dioxide is released during respiration and must be gotten rid of.

Question 8

What are the requirements for an efficient gaseous exchange surface area?

Answer 8

1. Large surface area- the larger the surface area the more quickly the gases can move through it.
2. Thin surface area- usually one cell thick
3. Moist surface area- gases dissolve in water and then pass through.
4. Adequate ventilation- to provide fresh oxygen and remove carbon dioxide.
5. Adequate protection- to prevent cells from being damaged.
6. Efficient mode of transport of gases- blood carries oxygen from the lungs and carbon dioxide towards the lungs.

Question 9

What are the nasal passages?

Answer 9

The open spaces in the nose.

Question 10

What is the function of the nasal passages?

Answer 10

They act as a moistener, a filter, and warm up the air before it reaches the lungs.

Question 11

What is the function of the nasal hairs?

Answer 11

They prevent various foreign particles from entering the airways.

Question 12

What is the mucous membrane?

Answer 12

A membrane made of ciliated columnar epithelium containing goblet cells. The membrane secrets a sticky fluid called mucus.

Question 13

What is the function of the mucous membrane?

Answer 13

The mucus secreted by the membrane and the cilia on the membrane collect dust, bacteria, and air particles. Mucus also moistens he air.

Question 14

How does the air get warmer?

Answer 14

Under the mucus membrane there are a large amount of capillaries. The blood within the capillaries helps to warm the air as it passes through the nose.

Question 15

What is the pharynx and larynx.

Answer 15

The pharynx is the throat and the larynx is the voice box.

Question 16

What is the structure of the larynx?

Answer 16

The voice box is constructed mainly of cartilage, which is a flexible connective tissue. The voice box has two membranes stretched across the inside called the vocal chords.

Question 17

How do humans make sounds?

Answer 17

As air is expired, the vocal chords vibrate. Humans can control the vibrations of the vocal chords, which enables us to make sounds.

Question 18

What is the function of the epiglottis?

Answer 18

It prevents food and liquid particles from entering the larynx to prevent choking when swallowing.

Question 19

What is the trachea?

Answer 19

The windpipe.

Question 20

Why does the trachea have cartilage rings?

Answer 20

1.It keeps the trachea open to allow for air the pass through.
2. The C- shape allows for the oesophagus to have room to expand when swallowing.

Question 21

Bronchi

Answer 21

Around the center of the chest, the trachea divides into two cartilage-ringed tubes called bronchi. This section is also lined with ciliated cells. The bronchi enter the lungs and spread into a treelike fashion into smaller tubes called bronchial tubes.

Question 22

Bronchioles

Answer 22

The bronchial tubes divide and then subdivide. By doing this their walls become thinner and have less and less cartilage. Eventually, they become a tiny group of tubes called bronchioles.

Question 23

Alveoli

Answer 23

Each bronchiole ends in a tiny air chamber that looks like a bunch of grapes. Each chamber contains many cup-shaped cavities known as alveoli. The walls of the alveoli, which are only about one cell thick, are the respiratory surface.

Question 24

What makes the walls of the alveoli and efficient gaseous exchange surface?

Answer 24

They are thin, moist, and are surrounded by several numbers of capillaries.

Question 25

What happens at the walls of the alveoli?

Answer 25

The exchange of oxygen and carbon dioxide between blood and air occurs through these walls.