The stomata and their guard cells allows this happen.
Stomata is like a hole or gap on a leaf, most of them are present in a bottom side of the leaf, since waxy cuticle is not present over there. And 2 guard cells make up a stomata.
Guard cells are able to control the size of the stomata, depending on the situation. For example, the guard cells close up during day time because a lot of sunlight may cause more water loss.
In conclusion, guard cells and the stomata are the main structures that allow carbon dioxide and oxygen (water too) diffuse in and out of leaves.
The baby is used to getting what it needs through the placenta, which includes oxygen. The baby's lungs are initially filled with amniotic fluid.
TB. It is open to change.he thing about science is that a discovery may be made today and written up but by tomorrow something else is found that edifies what was found or proves it incorrect or make it obsolete. .Therefore the answer is <span>B. It is open to change</span>
ans is D. Most items are features in the spinal cord, but the hippocampus is in the brain.
Answer: 4 Guanines
Explanation: Following Chargaff's ratio that describes the ration of purines to pyrimidines as 1:1, if there are 23 purines, it follows that there should be 23 pyrimidines; 15 Thymines should therefore be hydrogen bonded to 15 Adenines by complementary base pairing.
We are then left with 8 nucleotides composed of guanines and cytosines in complementary base pairs. This means that half that number (4) should be guanines and the rest cytosines.