Question

Organisms may contain up to five levels of organization within their bodies. Which level of organization is shown by the liver?
tissue
organ
organism
organ system

Answer 1

Organisms may contain up to five levels of organization within body.

Lever is an organ, which are made up of tissues.

Organs are the body's recognizable structures which performs specific tasks.

The liver's main job is to filter the blood coming from the digestive tract, before passing it to the rest of the body.

Answer 2

There are Eight levels of organisation in the body, a organism "may" contain upto five levels of organisation within their bodies. The organisms which constitute Eight levels of organisation are Humans (others may have 5 levels only) namely, Organism (first level, example Humans), Organ-System (Second level, Digestive system, respiratory system, etc.), Organ (third level, Stomach, lungs, etc.), Tissue (fourth level, epithelial cells, pseudostratified epithelial cells and simple cubodial cells and simple squamous epithelial cells, etc.), Organelles (Mitochondrion, Nucleus, Ribosome, endoplasmic reticulum, golgi apparatus or complex, etc.), Molecules (Sugars, Proteins, water, vitamins, carbohydrates, etc.) and Atoms (Carbon, Hydrogen, Oxygen, Nitrogen, etc.).

Liver is belonging to the organ system (Highest system or the first level of structural organisation) and is henceforth named as a $\textbf {"Organ"}$.

Liver is a biosynthetic machinery for converting drugs to harmless substances (including poisonous un-required harmful constituency of other components). It also serves in Digestive System (Releasing if enzymes and non-enzymatic substances), Circulatory system (Conversion of deoxygenated or impure blood without oxygen to pure or oxygenated blood with the infusion of oxygen), Excretory system (helping in deamination or removes one excess of amine group from the molecule, secretes bile to excrete the bile pigments along with elimination of bilirubin and removing from the body, etc.) and the Endocrine system (Synthesisation and excretion of hormones, hormones such as IGF-1 related by pituitary gland is a growth hormone and has effects similar to insulin, sometimes liver cells are binded by the help of its receptors so it also secretes the same hormone.). It also has multitude of functions, as, it controls and regulates the blood volume in the body through enzymes and breakdown of it and also does synthesis for blood clotting (improvised blood clotting factor).