Unit 1 Section 4: The gaseous Exchange System Flashcards Preview

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Flashcards in Unit 1 Section 4: The gaseous Exchange System Deck (17)
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1
Q

gaseous exchange system in mammals is based around

A

the lungs

2
Q

basic structure of gaseous exchange system

A
  • Air enters the Trachea (windpipe
  • Trachea splits into two bronchi (One bronchus to each lung)
  • Each bronchus branches off into smaller tubes called bronchioles
  • On the end of Bronchioles are air sacs called alveoli (where gases are exchanged
  • in order for this system to work the ribcage, intercostal muscles and diaphragm must work together to ove air in and out
3
Q

Alveoli

A
  • form the gaseous exchange Surface
  • arranged in bunches on the end of Bronchioles
  • surrounded by capillaries giving each alveolus its own blood supply
  • made from a single layer of thin, flat cells called alveolar epithelium.
  • Capillary walls made from capillary Endothelium (still a type of epithelium)
  • alveoli walls contain Elastic Fibres to help the alveoli return to their normal shape after inhaling/exhaling air.
4
Q

Gas exchange in the alveoli

A

*oxygen difuses out of alveoli across epithelium into haemoglobin in the blood
*Carbon Dioxide difuses into the alveoli crossing endothelium from the blood
It is then breathed out

5
Q

most exchange surfaces have 2 things in common…

A
  • Large surface area to increase the rate of diffusion

* Thin providing a short diffusion pathway which increases the rate of difusion

6
Q

Lung adaptions

A
  • Many Alveoli increase surface area
  • Alveolar epithelium and Capillary endothelium are only 1 cell thick
  • Alveoli have a good blood supply (constant exchange of CO2 and Oxygen) maintaining the concentration gradient
  • Diaphragm and intercostal muscles involved in ventilation ( keeps high concentration gradient)
7
Q

Goblet Cells

A

*secrete mucus - which traps microorganisms and dust particles in the inhaled air (bronchus/Trachea/Bronchiole)

8
Q

Cilia

A

*hair-like structures on the suface of epithelial cells.
*beats mucus
*moving mucus and trapped microorganisms towards the throught where it is swallowed.
(Bronchus/Trachea/Bronchiole)

9
Q

Elastic Fibres

A

*breathing in inflates lungs and Fibre stretch
*Fibres recoil to help puch the air out when exhaling
(Bronchus/Trachea/Bronchiole/Alveolus)

10
Q

Smooth muscle

A

*allows control of airway diameter
*Muscles Relax making the tubes wider meaning less resistance to air flow (during exercise)
(Bronchus/Trachea/Bronchiole)

11
Q

Cartillage

A

*Provides Support
*Strong & Flexible
*Prevents collapsing when breathing in and the pressure drops
(Bronchus/Trachea)

12
Q

Distribution of features: Trachea

A
  • Large C-Shaped Cartilage pieces
  • Smooth muscle
  • Elastic Fibres
  • Goblet Cells
  • Ciliated Epithelium
13
Q

Distribution of features: Bronchi

A
  • small Pieces of cartilage
  • Smooth muscle
  • Elastic Fibres
  • Goblet Cells
  • Ciliated Epithelium
14
Q

Distribution of features: Larger Bronchiole

A
  • No Cartilage
  • Smooth muscle
  • elastic Fibres
  • Goblet Cells
  • Ciliated Epithelium
15
Q

Distribution of features: Small Bronchiole

A
  • No Cartilage
  • Smooth muscle
  • elastic Fibres
  • No Goblet Cells
  • Ciliated Epithelium
16
Q

Distribution of features: Smallest Bronchiole

A
  • No Cartilage
  • NoSmooth muscle
  • elastic Fibres
  • No Goblet Cells
  • No Cilia
17
Q

Distribution of features: Alveoli

A
  • No Cartilage
  • NoSmooth muscle
  • elastic Fibres
  • No Goblet Cells
  • No Cilia