- Blood Cell
- Heart Muscle Tissue
- Heart
- Circulatory System
- Fish
A cell is the smallest functioning unit of an organism, so it's the least complex of all. Followed by tissue, the organ (heart), the circulatory system and the organism, which is the fish.
Answer:
I think that the correct answer is B
Volume since it relates to surface area to volume ratio
Either adenine and guanine or thymine and cytosine. It is either because the first adenine pairs with thymine and guanine pairs with cytosine, So each rung will have one of the two pairs.
They transport oxygen to all the cells of the body