They develop into the cell wall and cell membrane
High quantities of nutrients in water from industrial crop fertilizers and animal waste cause excessive aquatic plant growth — a process known as “eutrophication,” which, in turn, causes “hypoxia,” or water that is low in oxygen. Harmful algal blooms (or HABs) occur when aquatic algae grow rapidly out of control.
I'm not sure but I thinks the first animal that produce bacteria is Pig.
It is C as to have freckles you have to have a dominant and recessive gene (can be worked out using a punnett square) as the child has 50% of not having freckles like his dad or 50% having freckles like his mom.
male genes(homozygous recessive)
f f
female F Ff Ff
genes
f ff ff
so ff is not having freckles and being homozygous recessive, or Ff having freckles and being heterozygous.
So the child is heterozygous so C