Sinlge-celled organisms and soft, boneless animals. Back then organisms were single-celled and simple.
The zygote, a single cell, implants its self to the uterine wall and it developes into an embyro which is a cluster of cells.
D! They are both decomposing dead organic matter and metabolizing it through certain pathways to obtain energy! Hope this helped :)
I think its called a <span>volcanic neck.</span>
It’s the photic zone!!!! I learned this last year
