B1.5 The respiratory system, breathing and respiration - the respiratory system

Question 1

Human respiratory system

Answer 1

A system of organs, functioning in the process of gas exchange between the body and the environment, consisting of the trachea, bronchi, alveoli and lungs

Question 2

Need for a respiratory system

Answer 2

Large organisms require a complex respiratory system in order to obtain a sufficient volume of oxygen to maintain a high level of aerobic respiration and to remove an equivalent volume of waste carbon dioxide

Question 3

Gaseous exchange

Answer 3

The process where oxygen is taken in and exchanged for carbon dioxide which is a waste product of respiration

Question 4

Sites of gas exchange

Answer 4

The alveoli of the lungs and respiring cells around the body

Question 5

Oxygen

Answer 5

A gas that is needed for aerobic respiration to release energy, oxygen is transported into the body by the respiratory system and around the body by the circulatory system

Question 6

Carbon dioxide

Answer 6

A waste product of respiration that needs to be removed from cells via the blood and removed from the body via the respiratory system

Question 7

Lungs

Answer 7

The main organs of the respiratory system, responsible for gas exchange where oxygen is exchange with carbon dioxide in the blood

Question 8

Nasal cavity

Answer 8

A hollow space behind the nose that regulates the flow of air into the respiratory system

Question 9

Trachea

Answer 9

Allows air to pass to and from lungs

Question 10

Bronchi

Answer 10

Two short branches at the lower end of the trachea that carry air into the lungs

Question 11

Bronchioles

Answer 11

Airways in the lungs that are made up of multiple branches, leads from the bronchi to the alveoli

Question 12

Alveoli

Answer 12

Tiny sacs of lung tissue where gaseous exchange takes place with the blood

Question 13

An effective exchange surface

Answer 13

Has a large surface area, a good blood supply, is well ventilated for gas exchange and has a thin membrane for diffusion

Question 14

Capillary network

Answer 14

An interconnecting network of capillaries surrounding the alveoli for optimised gas exchange

Question 15

Capillaries

Answer 15

Small and thin blood vessels where the exchange of molecules such as oxygen and carbon dioxide takes place, they consist of a single layer of cells

Question 16

Diaphragm

Answer 16

A large muscle at the bottom of the chest cavity that helps control breathing, when the diaphragm pulls down and contracts to become flat, air can easily enter the lungs

Question 17

Intercostal muscles

Answer 17

Muscles in between the ribs which move the rib cage during breathing

Question 18

Pleural membrane

Answer 18

Double-layered membrane that encloses and protects each lung

Question 19

Pleural fluid

Answer 19

Fluid necessary to prevent friction between the pleural membranes

Question 20

Mucus and cilia

Answer 20

Help protect the respiratory system, particles and bacteria stick to mucus and the cilia moves the mucus out of the respiratory system to the back of the throat

Question 21

Surface area to volume ratio

Answer 21

The amount of surface area in relation to how large something is, a larger surface area to volume ratio leads to faster diffusion rates

Question 22

Diffusion

Answer 22

The movement of substances such as gas particles or substances in solution, from a higher concentration to a lower concentration

Question 23

Adaptations of the respiratory system

Answer 23

Large surface area due to multiple branches of bronchioles and many alveolar sacs, good blood supply for quick diffusion, well ventilated, ventilation is optimised by effective involuntary muscular action