Cells are the basic unit of life and all living things are made up of cells – plants, animals and of course humans! Understanding cell biology is critical for anyone keen to work with living things — from home gardeners to health professionals. The course also offers a solid foundation to enhance your knowledge base for a career in biology, biochemistry, animal studies or health sciences.

The Introduction to Cell Biology is a professional development course that will introduce you to both plant and animal cells, their structure, and how they function. Online biology courses that focus on cells will give you insights into DNA, genes and chromosomes, and the composition, membranes and protein structure of cells.

You will also learn about how cells communicate, cell division, the intracellular compartments of cells and the cell cycle and tissue formation.

Learning Outcomes

Outcomes achieved by undertaking online biology courses include:

• Learning about plant and animal cells, their structure
• Gaining an understanding of the history of cell biology
• Exploring prokaryotic and eukaryotic cells
• Studying cell structure, size and shape
• Gaining insights into the nucleus and the nucleolus
• Understanding euchromatin and heterochromatin
• Learning about cell composition and chemistry
• Exploring lipids, carbohydrates, proteins, enzymes and nucleic acids
• Studying cell membranes and golgi apparatus
• Gaining insights into DNA, chromosomes, genes and genetics
• Examining DNA replication
• Understanding telomeres and telomerase
• Learning about Greg Mendel’s genetic experiments
• Exploring gene mutations and phenotype and genotype
• Studying hereditary modifications in plants
• Gaining insights into meiosis and mitosis in cell division
• Understanding cell membranes including plasma membranes
• Learning about the structure of cell membranes
• Exploring the movement of molecules through cell membranes
• Studying Endocytosis osmosis and filtration
• Gaining insights into hydrostatic pressure
• Examining electrochemical gradient
• Understanding nutrient and waste exchange in animal cells
• Learning about mediated and non-mediated transport
• Exploring ionophores
• Studying protein structure and function
• Gaining insights into primary, secondary and tertiary structures
• Examining globular proteins
• Understanding protein organisation
• Learning about protein synthesis
• Exploring the function of ribonucleic acid in protein synthesis
• Studying transcription and translation
• Gaining insights into initiation, elongation and termination
• Examining food, energy, catalysis and biosynthesis
• Understanding energy, catabolic and anabolic metabolism
• Learning about animal and plant tissues
• Exploring tissue renewal

 

And more!

15 Fascinating Facts About Cells

The word “cell” is derived from the Latin word “cella” which means “small room”. Each cell is a self-contained and partially self-sufficient compartment designed to carry out a limited series of functions. And as you’ll learn in online biology courses such as our Introduction to Cell Biology, while the structure and function of cells are highly variable, their basic structure is similar. Here are some fascinating facts about cells.

• Cells are the smallest biological unit of life found in all organisms.
• It is estimated that cells first appeared on Earth around 3.5 billion years ago.
• All cells are bound by an outer membrane and contain DNA and cytoplasm.
• Organisms can have one of two classifications — unicellular or multicellular.
• A unicellular organism only has one cell, and an example is bacteria.
• A multicellular organism has more than one cell, and an example is a human!
• There are two different types of cells — eukaryotic or prokaryotic.
• Eukaryotic cells have a nucleus and can be unicellular or multicellular organism.
• Prokaryotic cells do not have a nucleus and are unicellular organisms.
• “Cell division” is the process where one cell divides itself into two or more cells.
• It is estimated that the average human body has around 40 trillion cells.
• The human brain alone contains around 80 billion cells.
• The human body has around 200 different types of cells, including blood, bone, fat, stem and skin cells.
• Blood cells in the human body include platelets and red and white blood cells.
• Bone cells in the human body include osteoclasts, osteoblasts, osteocytes and osteoprogenitor cells.

How Long Do Cells Survive?

Cells die just like all living things, and an adult male loses around 96 million cells per minute! Fortunately, in that same minute around the same amount have divided, replacing those that have died. Just as you shed dead skin cells, the dead cells from your internal organs pass through and out of your body with waste products. However, the length of a cell’s life can vary. For example, white blood cells live for around 13 days, the top layer of your skin’s cells about 30 days, red blood cells for around 120 days and your liver cells about 18 months.

History of Cell Biology

When you study online biology courses, in particular those focusing on cells, you will gain insights into the history of cell biology. Cell theory states that all organisms are composed of cells, which are similar units of “organisation”.

The first bacteria and protozoans were observed by Antonie van Leeuwenhoek between 1632 and 1723 and the first division of cells by Hugo von Mohl in 1835. However, the concept of cell theory was formally articulated in 1839 by Matthias Jakob Schleiden and Theodor Schwann, and it has remained the foundation of modern biology. The idea predates other great theories of biology including Darwin’s Theory of Evolution in 1859, Mendel’s Laws of Inheritance in 1865, and the establishment of comparative biochemistry, including the work of Ernest Baldwin in the late 1930s.

The First Discovery of Cells

The invention of the microscope allowed scientists to gain further insights into what living forms were composed of. The word “cell” was first coined by English scientist Robert Hooke in 1665, in a book he called Micrographia. However, what he saw was the dead cell walls of plant cells in cork, and it did not indicate the nucleus and other organelles found in most living cells.

The first person to witness a live cell under a microscope was Anton van Leeuwenhoek, who in 1674, described the algae, Spirogyra.

In 1838, Schwann and Schleiden were enjoying an over-coffee conversation on their studies on cells. Schwann was struck by the similarity of the plant cells with nuclei that Schleiden was studying to the cells he had observed in animal tissues. So, both proceeded to Schwann’s lab to look at his slides! Schwann’s book on plant and animal cells (Mikroskopische) was published the following year, and his observations were that:

• The cell is the unit of physiology, structure and organisation in living things.
• The cell retains a dual existence as a distinct entity and a building block in constructing organisms.
• Cells form by free-cell formation (spontaneous generation), similar to the formation of crystals

We now know that although his first two observations were correct, the third was not. The correct interpretation of cell formation by division was formally enunciated by physician Rudolph Virchow in the late 19^th century when he stated that “all cells only arise from pre-existing cells”.

Modern Cell Research

With the rapid growth of molecular biology in the mid-20th century, cell biology research reached dizzying heights in the 1950s. It now became possible to grow, maintain and manipulate cells outside of living organisms. In 1951, cell biologist George Otto Gey cultured the first continuous cell line, which was derived from cervical cancer cells taken from a patient named Henrietta Lacks. They were eventually referred to as HeLa cells, signifying a breakthrough in the study of cell biology in terms of the structure of DNA.

In the following decade, the study of cells was aided by advances in electron microscopy and transfection methods (among others). Today, the function and structure of cells continue in a branch of biology called cytology, and cytology microscopes have allowed this field to progress, particularly in clinical settings.

 

Gain a solid introduction to cell biology to enhance your career and understand your body in a whole new light with online biology courses such as our Introduction to Cell Biology.