Cell Structures and Organelles

A comprehensive vocabulary review of cell biology, covering organelle structures, functions, and distributions across plant and animal cells.

Cell membrane

A structure that surrounds the cell, controls the kind of substance that enters (particularly taking in water and nutrients), and allows the discharge of waste materials; found in both plant and animal cells.

Nucleus

The organelle that controls the activity of the cell and contains chromosomes as well as the nucleolus; found in both plant and animal cells.

Chromosomes

Threadlike DNA-containing structures located within the nucleus.

Nucleolus

The most distinct structure of the nucleus, where ribosomes are assembled.

Cytoplasm

A jellylike substance that contains the organelles, provides structural support to the cell, is essential for cellular metabolism, and plays a crucial role in biochemical reactions, energy production, and substance transport; found in both plant and animal cells.

Ribosome

Essential organelles for cellular functioning and survival that facilitate the synthesis of proteins; located in the cytoplasm and on the rough endoplasmic reticulum in both plant and animal cells.

Endoplasmic reticulum

An extensive network of membranes that plays a fundamental role in the transport, processing, and distribution of proteins and lipids within both plant and animal cells.

Rough Endoplasmic Reticulum (RER)

A type of endoplasmic reticulum that appears rough because it is studded with ribosomes; its functions include the synthesis of proteins and insulins in pancreatic cells.

Smooth Endoplasmic Reticulum (SER)

A type of endoplasmic reticulum whose outer surface lacks ribosomes; functions in lipid synthesis, carbohydrate metabolism, detoxification of drugs and poisons, and storage of ions.

Golgi apparatus

An organelle composed of a series of flattened sacs called cisternae that acts as the 'shipping center' of the cell, processing, packaging, storing, and sorting proteins and lipids into vesicles for transport and distribution; found in both plant and animal cells.

Cisternae

A series of flattened sacs that compose the Golgi apparatus.

Mitochondria

Known as the powerhouse of the cell; releases the energy needed for cell activities and survival through cellular respiration (ATP production); found in both plant and animal cells.

Vacuoles

Membrane-bound organelles that act as storage for water and substances; found in plant cells and some animal cells.

Lysosomes

Organelles containing digestive enzymes that break down molecules and unwanted cellular materials, facilitate cellular digestion by disposing of waste and recycling nutrients, and defend against pathogenic invasions; found in both plant and animal cells.

Chloroplasts

Structures found in plant cells that serve as the site of photosynthesis and contain the green pigment chlorophyll.

Chlorophyll

The green pigment found inside chloroplasts that is responsible for capturing light energy.

Centrioles

Cylindrical structures found in animal cells that aid in cell division and are mainly composed of the protein tubulins.

Cell Wall

A rigid outer layer found in plant cells that is made up of cellulose, provides structure, support, and protection, and prevents the cell from bursting when water enters.