Top Posters
Since Sunday
a
5
k
5
c
5
B
5
l
5
C
4
s
4
a
4
t
4
i
4
r
4
r
4
New Topic  
dontstealmypeng dontstealmypeng
wrote...
Posts: 8
Rep: 0 0
7 years ago
Which of the following is NOT a chemical barrier that helps prevent infections?
A. urine
B. mucus
C. tears
D. the pH of the blood
Read 1534 times
1 Reply
Replies
Answer accepted by topic starter
bio_manbio_man
wrote...
Educator
Top Poster
Posts: 33241
7 years ago
Sign in or Sign up in seconds to unlock everything for free

Related Topics

New Topic      
Explore
Post your homework questions and get free online help from our incredible volunteers
  1291 People Browsing
 115 Signed Up Today
Related Images
  
 282
  
 571
  
 271
Your Opinion
Which industry do you think artificial intelligence (AI) will impact the most?
Votes: 352