Which two structures are not present in animal cells? 1. Cell Wall and Nucleus 2. Golgi Apparatus and Mitochondria 3.Cell Wall and Chloroplast 4. Endoplasmic Reticulum and Cytoplasm

Cell Wall and Chloroplast

Explanation:

Animal cells have a cell membrane, not a cell wall. Animal cells also have no chloroplast, as that is what gives plants their green colour and allows them to photosynthesize

Hydrogen

Explanation:

hydrogen is the only element in group 1 on the periodic table that forms covalent Bond