Human Biology (Respiratory System)

Question 1

What is Cellular Respiration?

Answer 1

Cellular Respiration is the chemical process in which oxygen is used to make energy from carbohydrates (sugars) for cells.

Question 2

What must be supplied and what must be removed during cellular respiration.

Answer 2

Oxygen must be supplied to cells and carbon dioxide removed.

Question 3

Where does air enter the body

Answer 3

Through the nose or mouth.

Question 4

What is the part where the nasal cavity and the oral cavity join called?

Answer 4

The Pharynx (throat)

Question 5

What is the epiglottis?

Answer 5

A flap of tissue that closes off the trachea during swallowing to prevent food entering the trachea.

Question 6

What holds the vocal cords and is the area of the throat used for breathing, swallowing, and talking?

Answer 6

The larynx

Question 7

What is the trachea?

Answer 7

The trachea (windpipe) has many rigid rings of cartilage which stop it from collapsing. Its function is to carry air in and out of your lungs.

Question 8

Describe the structure of the trachea?

Answer 8

The lining of the trachea is covered with mucous and cilia to trap foreign particles. The cilia beat upwards to move trapped particles out of the trachea.

Question 9

What is the part where the trachea splits into two called?

Answer 9

The bronchi (bronchus for singular). These distribute the air throughout the lungs until reaching the respiratory bronchioles and alveolar sacs.

Question 10

What are the smaller bronchi called?

Answer 10

Bronchioles

Question 11

What are alveoli?

Answer 11

Alveoli are where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and breathing out (the site of gaseous exchange) and are found at the end of the bronchioles. Each is surrounded by a network of capillaries.

Question 12

What covers and lines the lungs?

Answer 12

The pleural membrane, which protects it from rubbing against chest cavity.

Question 13

What are the lungs?

Answer 13

The organs that contain the alveoli whose main job is to transport oxygen and remove extra carbon dioxide.

Question 14

What is inspiration (inhalation)?

Answer 14

The movement of oxygen into the body through the nasal or oral cavity.

Question 15

What occurs during inhalation?

Answer 15

• Thoracic cavity expands
• Volume of lungs increases
• Air pressure decreases
• Air rushes into the lungs

Question 16

How does the thoracic cavity expand?

Answer 16

The thoracic cavity expands due to:
- Intercoastal muscles contracting
- Ribs rise and move out
- Sternum moves forward
- Diaphragm contracts and moves down

Question 17

What is expiration (exhalation)?

Answer 17

The movement of carbon dioxide out of the body through the nasal or oral cavity.

Question 18

How does the thoracic cavity relax?

Answer 18

• Intercoastal muscles relax
• Ribs lower and move inwards
• Sternum moves backwards
• Diaphragm relaxes and moves up

Question 19

What occurs during expiration (exhalation)?

Answer 19

• Thoracic cavity relaxes
• Volume of lungs decreases
• Air pressure in the lungs increases
• Air rushes out of the lungs

Question 20

What are the 3 working units of the respiratory system?

Answer 20

• Pressure changing apparatus
• Respiratory passages (air conducting system)
• Alveoli - gas exchange

Question 21

Describe the passage of air

Answer 21

Nostrils (mouth) —> Nasal cavity —> Pharynx —> Larynx —> Trachea —> Bronchi —> Bronchioles —> Alveoli

Question 22

What does the amount of air vary based on?

Answer 22

The amount of air that enters and leaves the lungs varies depending on the rate and depth of inspiration and expiration.

Question 23

What does the rate and depth of breathing depend on?

Answer 23

The health, activity and emotional state of the individual.

Question 24

What is the relationship between the volume of the lungs and the pressure of air?

Answer 24

The greater the volume of the lungs, the lower the air pressure within the lungs.

Question 25

How is the volume of the lungs altered?

Answer 25

The volume of the thoracic cavity must change due to the relaxation and contraction of the diaphragm and intercoastal muscles.

Question 26

What is good about the pleural membrane sticking to the membrane of the lungs and thoracic cavity?

Answer 26

Once the thoracic cavity expands so does the lungs.

Question 27

What are the features of blood arriving in the capillaries?

Answer 27

Higher concentration of CO2
Lower concentration of O2

Question 28

What are the features of air in the alveoli?
(Air that is breathed in)

Answer 28

Higher concentration of O2
Lower concentration of CO2

Question 29

What are the pathways of diffusion during respiration?

Answer 29

Oxygen diffuses from the alveoli into the capillaries
carbon dioxide diffuses from the capillaries into the alveoli.

Question 30

What are the 4 features of alveoli that make them good at gas exchange?

Answer 30

1. Lots of them give the lungs a large surface area to volume ratio
2. Very small meaning they have a greater surface area
3. Surrounded by capillaries making the pathway of diffusion quicker
4. Thin walls which make the diffusion of O2 and CO2 easier
5. Highly elastic structures that can expand and contract during breathing. The elasticity of the alveoli allows them to stretch and increase in size during inhalation and can recoil during expiration. Increasing O2 intake and CO2 release.