Animal cell
Animal Cell

Animal Cell: Definition, 15 Organelles and Functions

Animal Cell Definition

Animal cells are common names for eukaryotic cells that make up animal tissue. Different from other eukaryotic cells, such as plant cells, because they have no cell walls, and chloroplasts, and usually they have smaller vacuole, not even any.

Because it does not have a hard cell wall, animal cells vary in shape.

Animal Cell Organelles and Their Functions

Cell Membranes

Cell membranes are the outermost parts that wrap around cells composed of fats and proteins.

Cell membrane functions are:

  • Protect cells
  • Recipient of outside stimuli
  • Regulate in and out of substances.

Endoplasmic Reticulum

Endoplasmic reticulum is a cell part that is in the shape of threads that exist in the nucleus of the cell. Endoplasmic reticulum is divided into two, namely fine endoplasmic reticulum (Smooth ER) and rough endoplasmic reticulum (REr). Smooth endoplasmic reticulum (Smooth ER) is not attached to ribosomes, while rough endoplasmic reticulum (REr) is attached to ribosomes.

Endoplasmic Reticulum Function:

  • Means of transporting substances in the cells themselves
  • Protein synthesis
  • Synthesizing lipids in cells
  • Helps in detoxifying harmful cells in cells\.


Cytoplasm is a fluid of cells and everything that dissolves in them, except the nucleus (cell nucleus) and organelle, and the cytoplasm consists of material and water proteins. Cytoplasm has a complex colloid i.e. Not liquid and not solid that can change depending on the concentration of water, if the concentration of water is low, it will become a soft solid or commonly called gel, but if the concentration of high water will become diluted called sol.

Cytoplasmic Function:

  • Source of cell chemicals
  • The place where cell metabolism takes place.


Mitochondria are the larger organelles that are machined in cells. Mitochondria are similar in shape to cigars or cigarettes that have two layers of membranes that are curved and called Crista. Oxygen and glucose combine in forming the energy (ATP) needed for metabolism and cellular activity in the organelle. Mitochondria in the form of stumps are called mitochondrion..

Mitochondrial Function:

  • Generate energy in the form of ATP
  • Cellular respiration.


Lysosomes are organelles in the form of pockets bound in membranes containing the content of hydrolytic enzymes used in controlling intracellular digestion under any circumstances.

Lysosome Function:

  • Insertion of macromolecules from the outside into cells with endocytosis mechanism
  • Digesting material using phagocytosis
  • Controlling intracellular digestion
  • Destruction of damaged cell organelle (autophagy)

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Microfilaments are organelle cells formed from actin and myosin proteins. Microfilaments bear a resemblance to microtubules but microfilaments are softer and smaller in diameter.

Peroxisome (Micro body)

Peroxisomes are small pockets containing catalase enzymes that are toxic to water and oxygen that harm cells. Peroxisomes are found in both liver and kidney cells.

Function of Peroxisome:

  • Deciphering the peroxide (H2O2) of toxic metabolic remains
  • Changes in fat to carbohydrates.


Microtubules are organelle cells in the cytoplasm found in eukaryotic cells and are cylindrical in length with an inner diameter of approximately 12 nm and an outer diameter of 25 nm. Microtubules are rigid.

Microtubules Function:

  • Protect cells
  • Role in the formation of flagella, cilia and centrioles
  • Give the cell shape.


Ribosomes are dense and small cell organelles with a diameter of 20 nm consisting of 65% RNA ribosomes (rRNA) and 35% ribosomes proteins (Ribonucleoprotein or RNP). Inside ribosome cells are bound to the rough endoplasmic reticulum (REr), or cell nucleus membrane.

Ribosomes Function:

  • The place where protein synthesis takes place.


Centrioles is a tube-shaped structure that can be found in eukaryotic cells. Centrioles also takes a role in cell division. A pair of Centrioles that form a combined structure is called a centrosome.

Centrioles Function:

  • Cell division process in forming spindle yarn
  • Playing a role in shaping cilia and flagella.

Golgi apparatus

The body of Golgi or Golgi apparatus is an organelle associated with the cell excretion function. Golgi bodies can be found in all eukaryotic cells and are found in excretion functions.

Golgi Body Functions:

  • Forming vesicles (sacs) for excretion
  • Forming plasma membranes
  • Forming lysosomes
  • Processing proteins.


The nucleus is the nucleus of the cell that regulates and controls cell activity both metabolically and to the division of cells.

Nucleus Function:

  • The place where replication occurs
  • To maintain the integrity of the genes
  • Control cell activity by managing gene expression
  • Controlling metabolic processes in cells
  • Store genetic information.


The nucleolus is an area in the nucleus of the cell responsible for the formation of proteins using RNA (ribonucleic acid).

Nucleolus Function:

  • Responsible for protein formation.


Nucleoplasm is a solid fluid that is in the nucleus of cells containing chromatin fibers.

Nucleoplasm Function:

  • Forming chromosomes and genes.

Core Membrane

The core membrane is the main structural element of the nucleus that wraps around the entire organelle and separates between the cytoplasm and the nucleus area.

Core Membrane Function:

  • Cell nucleus protector (Nucleus)
  • Place of exchange of substances between the nucleus material and the cytoplasm

Thank you very much for reading Animal Cell: Definition, Organelles and Functions, hopefully useful.

Last Updated on September 18, 2021 Reviewed by Market Health Beauty Team

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