respiratory system

Question 1

nasal cavity

Answer 1

• filters air by the nose hairs
• warms and moistens air before it enters the lungs
• mucus traps dust etc

Question 2

why does the air need to be moistened?

Answer 2

because gasses cannot diffuse through dry substances

Question 3

pharynx (throat)

Answer 3

air passes through to travel to lungs

Question 4

epiglottis

Answer 4

• a flap of tissue that closes during swallowing so food and liquid cannot enter the lungs

Question 5

bronchioles

Answer 5

• very fine tubes of smooth muscle
  -lead to the alveoli
• expands when the body needs more air
• when sick they are inflamed and filled with mucus

Question 6

alveoli

Answer 6

• tiny air sacs that make up most of the lung
  -occur in clusters
  -very thin walls that are lined with blood capillary for the exchange of gases

Question 7

diaphragm

Answer 7

• a muscle that separates from the chest and abdomen
• contracts and flattens downwards
• allows room for lungs when they inflate

Question 8

larynx (voicebox)

Answer 8

contains vocal cords that vibrate to make sound

Question 9

trachea

Answer 9

• contains C shapes cartilage that hold the structure open
• carries air to and from the lungs
• lined with mucus and cilia (beat to move the phlegm upwards) to trap any dust and debris

Question 10

lungs

Answer 10

• occupy all the space in the chest cavity except for the mediastinum where the heart in
• covered in a pleural membrane
• pleural fluid between the 2 layers that holds the lungs against the chest

Question 11

bronchi

Answer 11

-branch of the trachea into each lung
- has C shaped cartilage rings

Question 12

ribs

Answer 12

the framework for the chest

Question 13

intercostal muscles

Answer 13

• muscles between the ribs
• they move the ribcage upwards and outwards to allow room for the lungs when they inflate.

Question 14

what are the 2 types of ventilation called

Answer 14

inspiration and expiration

Question 15

what is the 3 step process of inspiration

Answer 15

1. -intercostal muscles contract extending the ribcage up and out
   - diaphragm contracts and flattens, extending the chest cavity downwards
2. the lung volume increases
3. air flows from high pressure outside to low pressure inside lungs

Question 16

what is the 3 step process of expiration

Answer 16

1. • rib cage moves down and inwards as intercostal muscles relax
   • diaphragm relaxes, doming up and pushing into the chest cavity
2. lung volume decreases
3. air flows from high pressure inside the lungs to low pressure outside

Question 17

ventilation

Answer 17

the process by which air is moved into and out of the lungs

Question 18

how is the concentration gradient maintained

Answer 18

• continuous flow of blood
• continuous ventilation

Question 19

where does the exchange of gases take place

Answer 19

the alveoli

Question 20

NOBAD

Answer 20

number
only one cell thick
blood vessels
air movement
deep and moist

Question 21

Number

Answer 21

there are hundreds of millions of alveoli in the lungs that give them a huge SA to V ratio

Question 22

lungs are suited to the exchange of gases in the following ways

Answer 22

NOBAD

Question 23

Only one cell thick

Answer 23

very thin - 1micro meter - so gases can exchange efficiently

Question 24

blood vessels

Answer 24

bunches of alveoli are surrounded by blood vessels so they are well supplied with blood to exchage gases with

Question 25

air movement

Answer 25

the lung can change its volume by muscle movements

Question 26

deep and moist

Answer 26

the lungs are positioned eep in the body to reduce any evaporaion of the liquid that covers the respiratory surfaces. this is important because gases cannot diffuse through dry substances

Question 27

how is the concentration gradient maintained

Answer 27

- continuous flow of blood - continous ventilation