Page 31 - Modul Konsep Tekanan Zat Pada Makhluk Hidup

Materi Pembelajaran

Pernapasan

P e r n a p a s a n a d a l a h s u a t u p r o s e s p r o s e s p e r t u k a r a n g a s o k s i g e n d a n k a r b o n d i o k s i d a .
P r o s e s p e r n a p a s a n d i p e n g a r u h i o l e h s u s u n a n s a r a f o t o n o m . M e n u r u t t e m p a t t e r j a d i n y a
p e r t u k a r a n g a s , m a k a p e r n a p a s a n d a p a t d i b e d a k a n a t a s 2 j e n i s .
1 . P e r n a p a s a n l u a r ( E k s t e r n a l ) t e r j a d i n y a p e r t u k a r a n u d a r a a n t a r a u d a r a d a l a m
a l v e o l u s d e n g a n d a r a h d a l a m k a p i l e r .
2 . P e r n a p a s a n d a l a m ( I n t e r n a l ) a d a l a h p e r t u k a r a n u d a r a a n t a r a d a r a h d a l a m k a p i l e r
d e n g a n s e l - s e l t u b u h .
K e l u a r m a s u k u d a r a d a l a m p a r u - p a r u d i p e n g a r u h i o l e h p e r b e d a a n t e k a n a n u d a r a d a l a m
r o n g g a d a d a d e n g a n t e k a n a n u d a r a d i l u a r t u b u h . J i k a t e k a n a n d i l u a r r o n g g a d a d a
l e b i h b e s a r m a k a u d a r a a k a n m a s u k . S e b a l i k n y a , a p a b i l a t e k a n a n d a l a m r o n g g a d a d a
l e b i h b e s a r m a k a u d a r a a k a n k e l u a r .

P r o s e s p e r n a p a s a n s e l a l u t e r j a d i d u a
s i k l u s , y a i t u i n s p i r a s i ( m e n g h i r u p u d a r a )
d a n e k s p i r a s i ( m e n g e l u a r k a n u d a r a ) .
B e r d a s a r k a n c a r a m e l a k u k a n i n s p i r a s i
d a n e k s p i r a s i s e r t a t e m p a t t e r j a d i n y a
p e r n a p a s a n m a n u s i a d a p a t m e l a k u k a n 2
m e k a n i s m e p e r n a p a s a n , y a i t u

p e r n a p a s a n d a d a d a n p e r n a p a s a n
p e r u t . P e r n a p a s a n d a d a d a n p e r u t
t e r j a d i n y a s e c a r a b e r s a m a a n

Pernapasan Dada

P e r n a p a s a n d a d a m e r u p a k a n p e r n a p a s a n y a n g m e k a n i s m e n y a m e l i b a t k a n a k t i f i t a s o t o t -
o t o t a n t a r t u l a n g r u s u k ( i n t e r c o s t a ) . P e r n a p a s a n d a d a t e r j a d i m e l a l u i f a s e i n s p i r a s i d a n
e k s p i r a s i y a n g m e k a n s m e n y a s e b a g a i b e r i k u t :
Mekanisme Pernapasan Dada

F a s e I n s p i r a s i p e r n a p a s a n d a d a

O t o t a n t a r t u l a n g r u s u k ( m u s k u l u s i n t e r c o s t a l i s e k s t e r n a l ) b e r k o n t r a k s i - - > t u l a n g
r u s u k t e r a n g k a t ( p o s i s i d a t a r ) - - > P a r u - p a r u m e n g e m b a n g - - > t e k a n a n u d a r a
d a l a m p a r u - p a r u m e n j a d i l e b i h k e c i l d i b a n d i n g k a n t e k a n a n u d a r a l u a r - - > u d a r a
l u a r m a s u k k e p a r u - p a r u .

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