Question

difference between the outer layer of a branch of tree and outer layer of a young tree stem

Answer 1

Both have dermal tissue which is made of three layers-epidermis, mesodermis, endodermis.In the stem of young tree the outermost layer is epidermis whereas in stem of older tree or tree the outermost layer has one coating named bark which is made of suberin chemical.this chemical makes the bark impervious of moisture and poisonous air . Hopes this help u .

Answer 2

the stem of young tree is epidermis layer and in old tree it is bark which is made of suberin chemical and the bark will not allow fluid to pass and it poisonous air