Cell Theory and Key Scientists

The theory stating that all living organisms are composed of cells and that all cells arise from pre-existing cells.

The time period when life on Earth transitioned from single-celled to multicellular organisms, driven by increased oxygen levels and land becoming habitable.

An English polymath who was the first to use the term "cell" to describe the small, room-like structures he observed in cork.

A Dutch microbiologist who is often referred to as the "Father of Microscopy" for his contributions in observing living cells.

A Scottish botanist who observed oval structures within plant cells, later identified as the nucleus.

A German botanist who expanded on Brown's work and proposed that cells are the basic unit of life in plants.

A German physiologist who, collaborating with Schleiden, proposed that animal tissues are also composed of cells.

A German physician who observed diseased cells dividing to produce more diseased cells and proposed that all cells originate from pre-existing cells.

The process by which cells divide to create two genetically identical daughter cells.

Organisms that are made up of one cell.

Organisms that are composed of multiple cells working together.

The membrane-bound organelle that contains DNA and controls cellular functions.

The green pigment found in chloroplasts, crucial for photosynthesis.

The process of converting light energy into chemical energy in plant cells.

A large, fluid-filled sac found in plant cells, responsible for storing substances and maintaining cell shape.

A microscopic organism, like bacteria, that doesn't have a nucleus.

A more complex type of cell with a nucleus and other membrane-bound organelles.

Hair-like structures found on the surface of prokaryotic cells, involved in movement and attaching to surfaces.

Small, circular DNA molecules found in prokaryotic cells, separate from chromosomal DNA.

The watery substance within a cell, containing enzymes, molecules, and ribosomes.

The outer layer of a prokaryotic cell, providing structure and protection.

A layer of polysaccharides covering some bacteria, protecting from drying out.

The basic, self-sufficient unit of life that can reproduce and perform all necessary metabolic functions.

The molecule that carries genetic information and is passed on during cell division.

The membrane that encloses the cytoplasm of a cell and controls what enters and exits.

A network of tubules and flattened sacs that extends from the nuclear membrane throughout the cytoplasm.

Small structures responsible for protein synthesis.

A series of flattened, membrane-enclosed compartments that transport, package, and modify substances made by the ER.

Energy-generating organelles that are the powerhouses of the cell.

The nuclear envelope surrounds the nucleus, separating its contents from the cytoplasm. It maintains the nucleus's structure and includes pores that allow mRNA to exit for protein synthesis.

The nucleolus is responsible for producing essential molecules like mRNA, tRNA, and rRNA, which are crucial for protein synthesis and ribosome formation.

Chromatin is the loosely coiled form of chromosomes found within the nucleus. It contains DNA and associated proteins, playing a crucial role in cell division and genetic information storage.

The endoplasmic reticulum (ER) is a network of interconnected tubules and flattened sacs extending from the nuclear membrane. It acts as a transport system for materials within the cell, playing a vital role in synthesis and processing.

Rough endoplasmic reticulum (RER) is studded with ribosomes on its surface, making it essential for protein synthesis. These proteins are often destined for export outside the cell.

Smooth endoplasmic reticulum (SER) lacks ribosomes on its membrane and is involved in synthesizing lipids and steroids, as well as detoxification processes.

Ribosomes are small structures, either attached to RER or free in the cytoplasm, responsible for protein synthesis. Bound ribosomes produce proteins for export, while free ribosomes produce proteins used within the cytoplasm.

The Golgi apparatus, also known as the Golgi body, acts as the 'packaging counter' of the cell. It modifies, packages, and transports substances made by the ER, utilizing vesicles to store and transport materials out of the cell.

Mitochondria are energy-producing organelles that carry out cellular respiration, the process that converts nutrients into ATP, the cell's energy currency. They are often called the 'powerhouse of the cell'.

Vacuoles are fluid-filled sacs that store food, water, and chemicals. They are particularly large in plant cells and contribute to their structural support.