Eukaryotic Cell

Smooth ER

(A part of) endoplasmic reticulum that is tubular in form (rather than sheet-like) and lacks ribosomes. Its functions include lipid synthesis, carbohydrate metabolism, calcium concentration, drug detoxification, and attachment of receptors on cell membrane proteins.

Intermediate Filaments

A component of the cytoskeleton - important structural components of living cells. Their size is intermediate between that of microfilaments and microtubules. They are assembled from several different proteins. IFs crisscross the cytosol from the nuclear envelope to the cell membrane.

Chromosomes

A structure within the cell that bears the genetic material as a threadlike linear strand of DNA bonded to various proteins in the nucleus of eukaryotic cells, and in the mitochondrion and chloroplast of certain eukaryotes.

Microfilaments

A thin, helical, single-stranded filament of the cytoskeleton found in the cytoplasm of eukaryotic cells, composed of actin subunits, and functions primarily in maintaining the structural integrity of a cell and cell movements.

Rough ER

An endoplasmic reticulum (ER), a eukaryotic organelle made up of a system of membranous tubes and sacs, that is studded with ribosomes on its surface giving it a rough appearance under the microscope (hence its name).

Nucleus

Cell nucleus is supposed to be the brain or the control center of the cell and thus one of the most important animal cell parts. It contains the genetic material i.e. the DNA (Deoxyribonucleic acid) and the chromosomes. The DNA is made up of nucleotides which eventually help in protein formation by the process of transcription and translation.

Centrioles

Centrioles lie near the nucleus and are made up of nine tube like structures, each of which has three tubules. Centriole function includes releasing spindle like formations that attach to chromosomes during one of the cell division stages. Centrioles are responsible for the initiation of cell division.

Cell Cytoplasm

Cytoplasm is supposed to be the matrix or gel like substance/fluid present inside the cell. It is mainly made up of water and protein material. The cytoplasm is the key site wherein all life processes occur.

Microtubules

Fibrous, hollow rods, that function primarily to help support and shape the cell. They also function as routes along which organelles can move. They are typically found in all eukaryotic cells and are a component of the cytoskeleton, as well as cilia and flagella.

Lysosomes

Lysosome structure will contain enzymes. Lysosome function includes helping in the breakdown of larger molecules into small parts, also responsible for the transport of waste out of the cell. These are membrane bound sacs containing enzymes needed to break down unnecessary parts of the cell for reuse. It mainly helps phagocytosis and promotes intracellular digestion.

Golgi Apparatus

Made up of numerous layers which form a sac like structure. Golgi apparatus functions include protein packaging and its distribution to other parts of the cell. The proteins formed and bounded by the ER need to be processed so as to perform normal functions. Golgi, membranous sacs associated chiefly with the endoplasmic reticulum, do that to release the protein chains.

Chromatin

Mass of genetic material composed of DNA and proteins that condense to form chromosomes during eukaryotic cell division. Chromatin is located in the nucleus of a cell.

Microvilli

Minute projections of cell membranes which greatly increase the surface area of the cell.

Mitochondria

Mitochondria are among the largest cell organelles also known as the engine house of the cells. Oxygen combines with glucose to form energy (ATP) required for metabolism and cellular activities in this organelle. It is an independent organelle having its own Mitochondrial DNA, RNA and ribosomes owing to self replication and duplication.

Nucleolus

Nucleolus is a dark stained area inside the nucleus mainly responsible for the protein formation using RNA (Ribonucleic acid).

Ribosome

Ribosomes are thousands of tiny spherical structures that are are made of of RNA and protein enzymes. Ribosomes function includes helping out in protein synthesis process. These organelles could be bound to the endoplasmic reticulum or free floating in the cytoplasm.

Plasma Membrane

The cell's outer membrane made up of a two layers of phospholipids with embedded proteins. It separates the contents of the cell from its outside environment, and it regulates what enters and exits the cell.

Peroxisomes

These are types of microbodies found in cells, roughly spherical in shape, which contain enzymes responsible for degradation.

Endoplasmic Reticulum

This is a network of tubes, sacs and membranes, responsible for transporting material from one part of the cell to another. There are two types of endoplasmic reticulum; rough endoplasmic reticulum (lined with ribosomes) and smooth endoplasmic reticulum (lacking ribosomes/embedded ribosomes). The animal cell model clearly suggests ER to be the second largest cell organelle after mitochondria since these form a series of interconnecting flattened tubular tunnels; rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). The RER is mainly responsible for holding onto the proteins formed in the ribosomes, thus being rough in appearance.

Nuclear Envelope

This is the porous, protective sheath that covers the nucleus which allows influx of substances and is one of the distinctive characteristics of an animal cell. Read more on nuclear membrane function.