The following is defined as the level of organization in the body forming increasingly larger, more complex structures.

a.) cell, organ, tissue, organ system
b.) cell, tissue, organ system, organ
c.) cell, organ system, tissue, organ
d.) cell, tissue, organ, organ system

d. cell, tissue, organ, organ system

Explanation:

cells-the basic unit of life.

tissue- group of familiar cells with the same function and structure.

organ- a group of tissues of the same function and structure functioning together to perform a specific task

organ sustem- two or more organs functioning together to complete a specific process

D.) cell, tissue, organ, organ system

Explanation:

The cells are the smallest living organisms.

Those cells makeup a tissue.

Those tissues makeup an organ.

A group of organs make organ system.

cells use diffusion to get substances in and out of themselves. that diffusion will occur across the cell membrane or the outer covering of the cell. because we are talking about the surface of the cell, surface area and volume are  important factors here. as a cell increases in size, its surface area and volume increase as well.  we call that the surface area to volume ratio (sa: vol).  but the catch is that  volume increases at a greater rate than surface  area. in other words, as a cell gets bigger, the sa: vol gets smaller. so a really small cell like bacteria is mostly cell membrane (surface) with very little contents (volume). a really big cell like an egg, is mostly insides with a super thin membrane. so what ends up happening is that the cell cannot efficiently diffuse all of the stuff it needs in/out to survive. therefore cell size is limited to about 100mm. so how do we make organisms bigger than 100mm? cells divide! by dividing and becoming multicellular, organisms are able to grow!   check out the diagrams i attached to see the effect of sa: vol. i hope this ! good luck!

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.