Answer:
excretion is the action of expelling waste from one's body.
Explanation:
The nitrogen cycle is impacted by humanswhenever fertilizer is applied to farmland to help crops grow. This adds nitrates to the soil. If soil erodes, the nitrates are transported and deposited in the nearest body of water. This can cause algae to overgrow in a process called eutrophication. The lake will run out of oxygen as the algae die off and bacteria begin their decomposition.Sessile organisms are greatly affected.
Answer:
Humans release carbon dioxide (CO2) into the atmosphere through cellular respiration. This CO2 is used by plants during photosynthesis. During photosynthesis, plants release oxygen (O2) into the atmosphere. The oxygen is used by animals in order to carry out cellular respiration.
Explanation:
I put all I know into that so it should be right but if it isn't then I'm sorry
Answer:
D. The skin
Explanation:
The skin is usually considered as supply-independent for oxygen delivery. The most affected organs and tissues considered as being supply-dependent for oxygen delivery are heart, brain and lungs. These are the most sensitive to oxygen deprivation, being the brain more than the other organs.
ANSWER
The correct answer is A
<u>EXPLANATION</u>
From the equation 
<u>L.H.S.</u>
Fe = 1
O =2
<u> R.H.S</u>
Fe =2
O =3
Now, let try to balance the oxygen atoms first,
To do this, we know the Least Common Multiples of 2 and 3 is 6
To get 6 atoms of oxygen at L.H.S multiply 2 by 3 and on the R.H.S, multiply 3 by 2
L.H.S.
R.H.S
This means that, 3 should be in front of 
at the L.H.S and 2 should come before 
in the R.H.S of the equation
Now, we have
L.H.S.
Fe = 1
O = 6
<u>R.H.S</u>
Fe =4
O =6
The equation is still not balanced since Fe is not balance
The Least Common Multiple of 1 and 4 is 4
Which means that we need to multiply 1 by 4 at the L.H.S and 4 by 1 at the R.H.S
L.H.S.
R.H.S
We now, have
<u>L.H.S. </u>
Fe= 4
O=6
<u>R.H.S</u>
Fe =4
O=6
Hence the balanced equation is
