as 1 2 1 mammalian lungs

8/9/2019 As 1 2 1 Mammalian Lungs

1/12

Mammalian Lungs

• List the features of the mammalian lungthat adapt it to ecient gaseous exchange

• Describe, with the aid of diagrams andphotographs, the distribution of cartilage,ciliated epithelium, goblet cells, smoothmuscle and elastic bres in the trachea,bronchi, bronchioles and alveoli of themammalian gaseous exchange system;

•Explain the functions of cartilage, cilia,goblet cells, smooth muscle and elasticbres in the mammalian gaseousexchange system;


2/12


3/12

http://www.enchantedlearning.com/label/anatomy.shtml


4/12

aseous Exchange

• aseous Exchange is the movementof gases by di!usion between anorganism and its environment acrossa barrier such as the alveolus wall


5/12

"he lungs are a large pair ofin#atable structures lying inthe chest cavity

$ir can pass into the lungsthrough the nose and alongthe trachea, bronchi andbronchioles

%inally the air reaches tiny,air&lled sacs called alveoli' "he walls of the alveoli arethe surface where theexchange of gases ta(es

place


6/12

"he lungs are protected by the ribs' Movement ofthe ribs together with the action of the diaphragm)a layer or muscular tissue beneath the lungs*help to produce breathing movements

)ventilation*


7/12


8/12

"as(

• +iew the selection of lung slides• omplete a lung dissection• "hen answer the following -uestions as

fully as you can'''' (you can use Biology 1 p55 to help you)

.'/tate 0 ways in which the structure of thelungs allows ecient gas exchange )1*'

2'Explain why the barrier to di!usion mustbe as thin as possible ).*'0'Describe how a steep di!usion gradient is

achieved in the lungs )1*'


9/12

$nswers

.' /tate 0 ways in which the structure of the lungs allows ecient gasexchange )1*' Large surface area ).* provides more space formolecules to pass through ).*, plasma membranes surrounding thecytoplasm create a permeable barrier allowing di!usion of oxygenand carbon dioxide ).*, alveolus wall is one cell thic( creating a thinbarrier for di!usion ).*

2' Explain why the barrier to di!usion must be as thin as possible ).*' 3treduces the distance gases have to di!use ).*

0' Describe how a steep di!usion gradient is achieved in the lungs )1*'4lood brings carbon dioxide from the tissues to the lungs ensuringthe carbon dioxide concentration in the blood is higher than that ofthe air in the alveoli ).*, it also carries oxygen away from the lungs

ensuring that the concentration of oxygen in the blood is (ept lowerthan air inside the alveoli ).*, the movement of the lungs)ventilation* ensures there is a fresh supply of oxygen entering thelungs increasing the concentration of oxygen in the alveoli ).*,carbon dioxide is also removed by ventilation ensuring that theconcentration in the alveoli is lower than that of the blood ).*


10/12

"hin(5

6ead the sentence below''' 3s itcorrect7 3f not, why not7

$lveoli have thin cell walls& this decreasesthe distance that gases have to traveland speeds up rates of di!usion

$lveoli have thin cell walls& this decreasesthe distance that gases have to traveland speeds up rates of di!usion

$lveoli have thin walls& their walls are one cell thic(5


11/12

Mammalian Lungs



•Explain the functions of cartilage, cilia,goblet cells, smooth muscle and elasticbres in the mammalian gaseousexchange system;


12/12

Mammalian Lungs



•

Explain the functions of cartilage, cilia,goblet cells, smooth muscle and elasticbres in the mammalian gaseousexchange system;

as 1 2 1 mammalian lungs

Documents